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Discussion Starter · #1 · (Edited)
ok lets start off by getting the basics out of the way...

JUNGLEMANS LIST: When asking for assistance I suggest providing the following information:
Year/Model of the Vehicle -2013 Polaris Ranger 800XP Special Edition W/ EFI
Is vehicle new to current owner or been a one owner vehicle - Used, i just got it
Description of Problem- see detailed descriptions below
History of previous problems that might be related - the PRV dowel got stuck, took out the camshaft, PO tried to repair it and never finished
How old is the fuel/Ethanol or Non Ethanol - gas was low, i put good 91 octane in it, pressure is at 58PSI
How long since vehicle was last used and ran normally - No clue, i have never seen it long term run
When problem began (Example: After going through deep water or After filling Fuel Tank or after sitting unused for a year)
Did problem begin after Recent Modification or Accessory Addition -see description below, but yes aftertop end rebuild, new oil pump,2x 8mm PRV repair
Under what Conditions does Problem Occur - when it gets to operating temp? or after running for 3-5 minutes
Odors, Unusual Noises, Changes in "Feel" of Vehicle while Riding - smell of gasoline
Any repairs already attempted and the Outcome (Example: Cleaned Battery Terminals, no change) -see description below
Results of any Tests already performed (Compression, Spark, Voltage, Battery Condition etc.) - see descriptions below







2013 Polaris Ranger 800XP
8,000 (ish) miles
Fuel Pressure : 55-59 PSI ( cold and at idle)
Miles that I have personally rode it : 1/2 mile TOPS....


Background: I traded this unit NON RUNNING for a Mustang skidloader, the guy that i traded it to purchased it (supposedly) running from a farmer but it burned oil, so he did a top end rebuild on it, he got the REV6 kit W/ 80.0 mm pistions, new hydraulic lifters and a replacement cam, he did everything EXCEPT replace the cam... still didnt run. then traded it to me...

Repair #1 So when i started on it i found that the PRV dowel was completely locked in, it wouldnt budge, so i replaced the oil pump/water pump and seals, removed the dowel and replaced the dowel with the 2x 8mm ball bearing solution. PS. this was all done with the motor inside the unit! I have yet to pull the motor out...

Repair #2 I then soon realized that i was having a hell of a time turning over the motor... long story short, i had to tear apart the whole side of the motor agian and replace the cam that the previous owner did not replace....now its back together!

Repair/installation #3 I installed a water type heater that runs off the coolant, I bought this with plans of taking it up to the lake ice fishing, and i bought the kit off ebay used. it seems to be working just fine, i dont know if it matters BUT i want to list everything i did to it so im not leaving anything out....


NOW HERE IS THE PROBLEM/PROBLEMS
--------------------------------------------------------------

Day #1 I started the unit, let it idle, and then drove around me neighborhood for a couple minutes... i did NOT go over 20 mph. it acted like everything was perfect, idles smooth, runs fine, ect.

Day #2 i thought i should drive to the car wash and clean up the belly pan from the oil and antifreeze from repairs 1,2,and 3. So i turn on the ranger, it starts fine, and shifts into drive just fine, I drive 4 blocks ( about 150 degrees is what my gauge is showing for temp) and it starts to sputter, i give it a little gas and it comes out of it...for a second... then it continually gets worse... to the point where i turn around and start heading back home, i slow down for an intersection and i am unable to get it out of its "spit and sputter fit" so is just creeps along until it finally dies. I push it as far as i can but eventually have to get towed back to the house. the unit would NOT start, if i hold the gas pedal to the floor it acts like it is trying to start, but it also acts like it is backfiring out of the intake.

The next day, after cranking it over a bunch and trying to get it to run to no avail i installed a new battery because my battery tender kept running low... and the old battery was junk

Repair #4 I installed a brand new battery to isolate any battery issues

I installed a fuel pressure sensor onto the BACK side of the fuel rail were the test hose is located (PTO SIDE), to confirm pressure. when I turn the key on it SLAMS to 58 psi, it does drop a bit once the pump quits, but (when its running, because I left it on) it stays STEADY at 58 PSI.

I then pulled injectors, i held them into the rail and cycled the key, it is DRY as a bone.... no dripping that i can see, and i held a paper towel under it cycled a couple more times with no difference, the paper towel was dry also ( so it wasnt just me visually looking at it, it actually was not dripping. THEN I turned over the motor and watched for injector spray, it was even and a fine mist, exactly how they should be working IMO.

I checked spark next, I found that i had spark on the PTO ( Drivers) side and the plug was dry ( but had burnt oil on it), however on the MAG (passenger) side i was NOT getting spark (and the plug was oil fouled). the next day I replaced BOTH plugs, and it started right up. I thought i was a genius!...

I hopped in the unit and took off down the block, very conservatively i planned my route just in case it decided to fail again... and just like before it let me get about 4-5 blocks ( around 160 degrees in temp) away from home and it started to spit and sputter.... i limped it (downhill) ALMOST all the way home ( MAX of 5MPH) but it finally died out on me 1/2 block away from my house (which the last 1/2 is uphill... basically on a hard load the motor couldn't overcome it). Got towed home.

I pushed it into the garage, and just like last time it will crank and act like it is backfiring thought the intake? almost like my timing is off?? I removed the TMAP sensor to make sure it was clean, and for the heck of it i tried to turn it over... it popped off for a second AND it shot flames out through the TMAP hole.... So in my brain it is firing on the intake stroke? or atleast then the intake valve is open????

The next day i started looking at it again. Motor is cold. Still no start. 5:30 AM

I turned my head to timing... I evaluated the low hanging fruit first, i removed the camshaft position sensor & visually inspected the sensor itself, all looked good, i then looked into the wiring from the sensor to where it enters into the main harness ( about 12" of visible wire). There was no cuts, rubbing of wires, or what i could see as bad connector/connections. The only part i saw was that the heat sleeve that the wires sit inside had at one point in time got hot enough to melt and make it oblonged, it was exactly where the lower radiator hose sits... so im assuming it got hot from that hose. i wrapped the sleeve in electrical tape and reinstalled the sensor, being careful to not let it sit on the coolant hose.

I then evaluated the Crankshaft position sensor. I removed it, there was little crud, i wiped it off with my finger and reinserted it into the cover. I then inspected wiring, and visually the wires seem to not be broken, wore, or rubbed through in any way, i unplugged the connector and confirmed it seated well into its female counterpart.. pulled wires from both sides with the "5lb pull test" and all the connectors stayed in place.


I went to work and discussed the situation with a guy, there was no way my timing was internal if it starts & runs fine and then stops...he asked me to check the flywheel Woodruff Key for the possibility of a sheared key that is making my crankshaft sensor signal screwed up. I pulled the cover when I got home, and confirmed the key was not sheared. It was in tact and in good shape. I reinstalled the flywheel, and the cover, double checked the wiring on the CPS and for the heck of it I tried to start it, it spit and sputtered for a couple seconds, i held the gas pedal about 1/2 way out and it started to fire lightly.....

A couple more seconds and i was able to keep it running with my foot on the gas and no starter. i was "babying" it for another 20 seconds or so until i got brave enough to let off the gas completely and to my amazement it stayed running! I was astounded!

I did all my "quick checks" that I was unable to do while the motor wasnt running, i first confirmed fuel pressure 58PSI PERFECT,
Then I wiggle tested the injector wires ( specifically on the plug at the injector) to confirm no broken wires INSIDE the connector itself due to wiggling while driving/ idling, and it did not drop a cylinder
Then i wiggled/ moved spark plug wires all the way to the coil, no changes, im just waiting for a cylinder to stop firing and i cant make it drop!
I wiggled the crank AND the camshaft sensor wires, no changes
I wiggle the main harness, and the throttle position wires, no changes, nothing i wiggle will make the motor start to missfire.
I check fuel pressure again 58... i rev it up at idle, it drops a hair down to 55psi but IMMEDIATLY comes back up to 57-58ish.
I go back to the sensors ( crank and Cam) and i "tap" the sensors while it is running, trying to get something to fail... nothing.

I then notice that i have a oil leak, but not out of a seal, this oil is coming out the top of the dipstick tube?????
I disconnect the lock to the dipstick and pull it out slightly...and oil starts to spray out the top of the tube with light pressure... my buddy who is sitting there with me says that i have a LOT of crankcase pressure and recommends we stop the engine and do a compression test. we pull both spark plug wires and the MAG plug, test compression and i get 80PSI!? HOWEVER we reinsert that plug and remove the PTO plug, and i get the same 80 PSI???? IMPOSSIBLE that that motor is running on 80psi.. my plugs were both oil fouled...

My buddy says that he thinks the previous owner installed the new top end improperly and the rings are probly cracked, so we stopped for the night and i figured i would start looking for a ring kit in the morning... HOWEVER then a different friend of mine texted and asked how the process was going so I ran everything past him and he said we were wrong, he said that the rings had not had a chance to break in yet and that i need to go run the motor hard to break in the rings, that once the rings are broke in i will have great compression and that his ranger that he rebuilt had the SAME issue with compression/blowing oil out the dipstick tube until he got his rings wore in.

This morning i took a chance and thought "what the hell" I was going to see IF my motor would get above 160 degrees ( as i have yet to see it actually reach operating temp). I turned it over and it started, i ran it at idle and just let it sit there. I figured 2 things, #1 i would have a less likely situation of wiggling (due to the road or wind) if its just sitting there idling, and #2 if it doesnt get above 160 and die i would then have a threshold for a temperature (wiring, sensor, etc.) problem. It reached 206 and the fan turned on! I let it continue to run, thinking that if it keeps running the pistion rings might get warm enough to break in....HOWEVER a couple minutes later it died and would not restart, same as the first and second time. Crank no start, backfire sounds like it is trying through the intake?

I pulled the tmap sensor out of curiosity if it would try to start again like before, it did not start or turn over differently. Fuel pressure was still at 58psi. I then pulled injectors, checked for a leaking injector while it was hot, it was fine.

I had to go to work, so i left the house... and immediately thought "shit" i should have checked the plugs! Is this all over oil fouled plugs! am i chasing my tail because the plugs will run long enough to get fouled out by oil and then the motor dies? or am i reaching a temperature where a sensor starts to fail and sends incorrect timing information to the ECM?

I am VERY close to being done, but i figured the geniuses (Jungleman, or any of the other regulars ) could chime in and tell me im an idiot and to look somewhere specific.
 

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Discussion Starter · #2 · (Edited)
Conversation with my local dealer is that i am testing all of the correct locations and I am going through all of the correct steps. the break in procedure for these rings is (i guess) to the extent of "run the piss out of it until it all seals up tight" So the last thing on my list to check is i am going to buy 3 new sets of plugs, Assuming that it will start i am going to put the new ones in and run the daylights out of it until it quits running, then im going to see if immediately replacing the plugs with new ones allows for it to start right back up again...if it does then i am going to run it until it stops again and repeat the process... hopefully i can get them wore in enough before i run out of spark plugs... (obviously all the while keeping a close eye on my oil level, and keeping that within spec)... I do not like this idea, as it does not explain or resolve the No start/backfire situation i spoke about in the beginning... but i can complete weed out the spark plug wires, plugs coil and ecm if this does work....
 

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2015 Polaris ranger 570 XP
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Maybe I missed it in your description but have you disconnected all the wiring connectors to the ECU and elsewhere to look for moisture that may have gotten into the connector when you were cleaning it up? It seems the problem began after the cleanup and that may mean something.

In addition, although I can't say your engine is made this way, some engines use an ignition system that fires both plugs at the same time when one cylinder is on the compression stroke and one is on the exhaust stroke (lost spark or dual fire). On those engines it would be impossible for plug wires to be crossed or to have an induced spark. On single fire engines, one spark specifically for each cylinder, not only is it possible to cross connect plug wires but wires running close together can cause an induced spark in a wire running to the cylinder not firing at that time. In such situations backfire or misfire can occur. Sometimes plug boots are not watertight, especially when wires are old and the boots get hard. Moisture under the boots can cause all kinds of misfire issues and any dirt on the outside of the plug can track the spark directly to ground rather than across the plug gap.
None of this may be happening in your case but it's simple and low cost to check these items.
 

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Discussion Starter · #4 ·
Pyromedic, I never actually made it to the car wash, so i still have not cleaned/power washed the unit itself.

I did not unplug all my ECU connectors and replug them all back in, however, it has only been sitting in my garage ( warm and dry) the last 3 weeks as i try to figure out these issues one at a time.

The spark on these 800's (if i understand correctly) is at the same time, both cylinders run concurrent with each other, and fire at the same time. but for the sake of discussion, the spark plug wires have little tabs that make it impossible to install them backwards to the coil itself.
 

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Discussion Starter · #5 ·
I called around to multiple dealers and asked them all similar questions regarding their thoughts, and for lack of better words its ALL over the board. 5 dealers, and 5 different answers...low compression, Coil going bad , Crank position sensor, Magneto is shorted out possibly and when warmed up makes connection, and one even said water in the fuel.... I am pulling at straws...


rebuild conversations online all tell me that i am testing all of the correct locations and I am going through all of the correct steps. the break in procedure for these rings is (i guess) to the extent of "run the heck out of it until it all seals up tight" So the last thing on my list to check is i am going to buy a couple new sets of plugs, Assuming that it will start i am going to put the new ones in and run the daylights out of it until it quits running, then im going to see if immediately replacing the plugs with new ones allows for it to start right back up again...if it does then i am going to run it until it stops again and repeat the process... hopefully i can get them wore in enough before i run out of spark plugs... (obviously all the while keeping a close eye on my oil level, and keeping that within spec)... I do not like this idea, as it does not explain or resolve the No start/backfire situation i spoke about in the beginning... but i can completely weed out the spark plug wires, plugs coil and ecm if this does work.... if it doesnt then it will probly just ruin my top end jugs and pistion rings.. which i will probly have to replace anyway...
 

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2008 Polaris Ranger 700 XP 4x4 EFI
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First off your compression check should be done with both spark plugs out and full throttle. Have you removed the crankscase breather valve on the valve cover and inspected it to make sure its not plugged. Also is your oil level good. I had one that was fine tell the oil heated up then a lifter collapsed, the oil was to low.
 

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Discussion Starter · #7 ·
First off your compression check should be done with both spark plugs out and full throttle. Have you removed the crankscase breather valve on the valve cover and inspected it to make sure its not plugged. Also is your oil level good. I had one that was fine tell the oil heated up then a lifter collapsed, the oil was to low.
I will redo the compression test tonight and post findings, when i did my compression test i did it with the plug in the opposite side.


I have removed the crankcase breather valve to inspect it, however i have not attempted to run it without it.


I will quadruple check my oil level, confirm that it is "full" and retry the process, but again with this i currently have too much crankcase pressure and oil is being pushed up my oil dipstick tube.
 

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Discussion Starter · #8 ·
First off your compression check should be done with both spark plugs out and full throttle. Have you removed the crankscase breather valve on the valve cover and inspected it to make sure its not plugged. Also is your oil level good. I had one that was fine tell the oil heated up then a lifter collapsed, the oil was to low.

I redid my compression test per your instruction, I am at 110psi on the mag side, and 120psi on the pto side.

I removed the crank breather and confirmed no obstructions like Monica Lewinsky

Oil level is adequate
 

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Discussion Starter · #11 ·
I called around to multiple dealers and asked them all similar questions regarding their thoughts, and for lack of better words its ALL over the board. 5 dealers, and 5 different answers...low compression, Coil going bad , Crank position sensor, Magneto is shorted out possibly and when warmed up makes connection, and one even said water in the fuel.... I am pulling at straws...


rebuild conversations online all tell me that i am testing all of the correct locations and I am going through all of the correct steps. the break in procedure for these rings is (i guess) to the extent of "run the heck out of it until it all seals up tight" So the last thing on my list to check is i am going to buy a couple new sets of plugs, Assuming that it will start i am going to put the new ones in and run the daylights out of it until it quits running, then im going to see if immediately replacing the plugs with new ones allows for it to start right back up again...if it does then i am going to run it until it stops again and repeat the process... hopefully i can get them wore in enough before i run out of spark plugs... (obviously all the while keeping a close eye on my oil level, and keeping that within spec)... I do not like this idea, as it does not explain or resolve the No start/backfire situation i spoke about in the beginning... but i can completely weed out the spark plug wires, plugs coil and ecm if this does work.... if it doesnt then it will probly just ruin my top end jugs and pistion rings.. which i will probly have to replace anyway...

This did nothing, I wasnt even able to get it going with new plugs the first time, so to run multiple plugs is off the table... I am turning my sights towords sensors
 

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Discussion Starter · #12 · (Edited)
I redid my compression test per your instruction, I am at 110psi on the mag side, and 120psi on the pto side.

I removed the crank breather and confirmed no obstructions like Monica Lewinsky

Oil level is adequate
Can anyone tell me what compression should be COLD & with fresh rings before they are broken in?


UPDATE 1/24/23: I contacted REV6 ( the company who sold the top end rebuild kit/ cam to the previous owner). I asked their tech/specialist (not the salesperson) about the compression situation, he stated that 110PSI, and 120PSI was fine for a fresh rebuild ( for now as it should still run off 110... but it wouldnt perform well... basically saying that it should not be the reason it doesnt start), and that if all i have done was idle and puts around for 30 min they would not expect my rings to be seated properly yet... so with that all being said they were not too concerned about "low compression" and advised that I look into electrical items a little bit more before tearing the top of the motor apart again.
 

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Discussion Starter · #13 · (Edited)
I did some electrical searching last night through my sensors, specifically looking for OBVIOUS wiring issues, and testing for accurate voltage/ OHM readings at the sensor with the mindset that a sensor cannot return a good signal IF it does not recieve the proper voltage in the first place. Keep in mind this first time around i only removed the shielding from the sensor itself to where it enters into the main harness. I did not enter into the main harness itself yet. Here is what I found.

CPS, I have 530 ohms between white and yellow. ( suppose to be 560.. i think i am close enough however i have a new sensor on its way, for now i will wait). I confirmed ground was "Open" with zero resistance, and then i confirmed that i have 2.4 Volts going into the CPS ( which if i understand correctly is that it works off a magnetic pendulum setup where it will go closer to zero or closer to 5 depending on the flywheel location, correct me if i am wrong). I do not like how the male plug from the harness seemed to have wires that were "pulled" out of the retainer clip/ they were stripped back from the plug about 1 cm with exposed wires if you remove the white retention band at the base of the clip, however after some extensive testing, I was able to determine that the plug itself just "looked" bad... but was still allowing voltage to pass through and the pins were still providing continuity. If i have my way long term i want to repair this, but for now it is on my radar and not a REQUIRED repair. I hope this decision doesn't bite me in the tail later.

T-MAP, i referenced the 5V that is going into the sensor, and confirmed that it had a ground going in, then from there i was able to find a pin that had a value of 2.7 coming out of it ( if i understand correctly, that is from the current air pressure, if i i was to blow on the sensor ( and changed the pressure) it should rise closer to 5V... I also found 2 wires that were damaged ( one pinched and one rubbed, i repaired both of them)

The throttle position sensor ( TPS) i found a blue wire that was pinched( i repaired it) then i confirmed good ground on pin 2 with zero resistance. I was in spec on 1-->2 and then also in spec on 2-->3. I then confirmed that i had 5V going into the unit and that when moving the pedal i had an increase in voltage coming from one of the wires going from 1.9 all the way up to upper 4's ( close to 5).

The Cam Phaser Sensor I did not get too last night, but i will get to it this afternoon . It should have 12V ( battery voltage) on the Red/Dark blue wire, and then ground on the brown. if i turn the motor over by hand it should flucuate on the orange/black wire that sends signal to the ECM.

I did not test the ECT ( Cngine Coolant temperature sensor) as it does not seem to be one of my issues... but now double thinking about it, if there is issues with this sensor and it is failed cold, it would basically let my motor start, but then it would continue to dump too much fuel and eventaully flood out my spark plugs. If it fails hot, it tell the ECM the put in too little amounts of fuel to start... this might have something too it.. idk?

Ignition Coil i measured between the connectors and i have 12V/ battery going into each wire/pin ( so no broken wires that i understand) The manual states .4 ohms of resistance.... if i remember correctly i was getting .6... i will double check this tonight also Update is below I was getting .6ohms


Long story short, i am hoping to get a lucky break, i really thought that i would stumble across a broken wire ( either see it, OR find a sensor with improper voltage/ground). and be able to back track it to wherever the issue is... but i was not that lucky last night. If anyone sees anything im missing please let me know.. otherwise i will continue down my wiring harness into the main harness. I hate disconnecting the ECM... but at this point im thinking i need to pull it to see if there are any melted pins.
 

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Discussion Starter · #14 · (Edited)
UPDATE:
I woke up early this morning to do some work in the garage before my 2yo woke up, I removed the remainder conduit/black sleeve & electrical tape from the main harness. I now have open/visable wiring with no tape/covers from the ECM all the way to my CPS ( minus the first 2" out of the ECM, and the CPS sleeve that runs after the plug,down the frame rail and almost all the way to the cps... i should do a continuity test on that wire now that i think of it.) I visually inspected ALL of the visible wires, and wiggle tested places of bending/concern. nothing was broken, and nothing snapped in the process of my testing. I then transferred my attention to the questions left above.. their answers are below.


My garage is at 55 degrees or so... the Temp sensor is at 1.5k ohms? which doesnt match the table in the owners manual, but its not too far off...so it is a place of "notification" but not something that i believe would make my motor not start.

The coil itself i probed and I received .6 ohm in response across 1-->2 & then the same .6 ohms from 2-->3, the manual states .4 ohms, but IMO I am using theirs as a reference point ( anything less than .4 would be cause of malfunction, OR if it was OL, that would mean a short, or if it was open that would mean a broken wire).

My replacement Crank position sensor & Cam shaft position sensor should be here this afternoon. I will install those and update. I dont feel like i am getting alot of traffic on this post, BUT for the sake of the next person with the same problem i will continue to post and keep updated. i hope the mass of information that i am posting will give a newbie ( like myself) a VERY detailed instructional on how to diagnose some of these issues.


If anyone has any input please let me know, i feel like i am getting close to drawing at straws now.
 

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Discussion Starter · #15 ·
Polaris dealer just called, he confirmed that the CPS, the wiring to the ECM, and the ECM itself is good ( supposedly). He also confirmed the the sensors are working properly. He pulled the side of the motor off to look at timing/ confirm that my marks all line up and he found some brass/gold filings in the oil there... he is thinking that a bearing ( rod, plane, or crank) is out. it did not make sense to me how/why a bearing like that would make my unit simply NOT run... I can see if it runs like shit, or if it doesnt have top end, or squeals like a bitch... but not run at all?


after discussing it with several people. the only way we can think that a bearing being out would effect a no start situation would be IF the crank bearings were completely out (side to side) and were allowing the crank itself to "walk" from the PTO to the MAG side and back.. essentially moving away from the CPS sensor that is mounted to the flywheel cover. If we were able to get it to start i was by pure luck that the flywheel had "walked" its way closer to the MAG side and was in line with the sensor. but when it walks away as im driving it looses its signal/magnetism, and from there it stops spark.

As of right now this is the ASSUMPTION, i will keep you all up to date.
 

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2011 Ranger 800 6xCentipede
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Hi JD,
Sorry to hear of your plight, but am interested in the steps you're taking in the troubleshhoting. I'm a newb when it comes to the electronics involved with FI engines, but am finding it more un-avoidable each day. Time to pull my head from the sand as it's getting harder to find things with Holleys or Mikuni's anymore!
Keep us up to date on your progress and your humor is not lost on me!
D McB
 

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It sounds like you are doing everything in a good logical order. I am not familiar with the 800 at all. That being said, there are a few items that I am thinking.
1, if the issue is mainly happening at 150 f +. The ECM might be going into "closed loop" at that temp. Get it running for a minute. the disconnect the temp sensor. It will force it into open loop. The fan should come on and the check engine light will be on. Let it fully warm up and see how it runs. The reason for this test is that I have seen vehicles have the adaptive fuel so far off they will not run until a ECM reset. FYI I have no idea if it possible to reset the ECM. Sorry.
2, Like I stated earlier, I do not know anything about the 800. On cars/trucks, I have seen bent/ chipped tone wheels do weird running issues. It sounds like it has not run correctly since the first rebuild attempt. Could it be possible that a tooth or bent tone wheel happened at that time? 2 ways to check for it. With a scope and/or to physically check the tone wheel either with a camera or mirror while turning the engine or very slowly.
3, Stator shorted to ground. Another far out there thought I know. On my own vehicle (truck) the alternator stator shorted and induced an A/C voltage into the electrical system. It caused the ECU to fire multiple sparks per cylinder. The darn thing was it did not do it all the time. Very hard to catch it. Again a scope found this issue also.

Good luck.
 
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