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Lt. if the ECU was really bad , you would have blink code 23 . The only way to know of course if a good ECU would solve your problems would be to try a known good one.
 

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Jungleman, I'm still here and still working with this Ranger. I had a little medical problem with the family, but I'm now able to devote some time to fixing this little [email protected]

I've just picked up a compression tester, so I'll get on compression/leakdown tests ASAP. In the meantime...in case the ECU is the culprit, what other models of Polaris products used a similar or compatible ECU? I was hoping to simply swap ECUs with another 2006 Ranger, but alas, they are no other Rangers of that year in my area. I think simply swapping in a known good ECU would solve a lot of trouble shooting, wouldn't it?

Gracias,
MQ
Nearly nothing is compatible..
This Polaris 4011370 ECU fits the following models and components:
Polaris Side by Side 2006 RANGER 6X6 EFI 700 - R06RF68AA Electrical/Battery
Polaris Side by Side 2006 RANGER XP 4X4 700 - R06RD68AA Electrical/Battery /Ab/Ac/Ad/Ae/Af

Compression check ? Engine hot..........both plugs out.......WIDE OPEN THROTTLE..
 

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Discussion Starter · #24 ·
OK, I finally got back to working on the Ranger. I do not have a compression tester available, but I was able to find a leak down tester. Bear in mind this engine was recently topped, and has less than 10 minutes total run time at idle. Both cylinders are leaking down at about 16-18 percent, mostly bypassing the rings. I can definitely hear the high pitched hissing through the oil fill and dipstick holes. Valves all seem tight, no noticeable noise or airflow at the throttle body or muffler. I'm still trying to locate a compression tester.

She still starts and idles nicely, and quits when the TPS voltage reaches 0.735 Volts. It just dies instantly at that particular voltage and throttle cam position. This position corresponds to just barely above idle. I've opened the wire looms and checked the three wires from the TPS, every inch, from TPS to ECU, including the splice to the airflow sensor, both with my continuity tester and while running at idle. I can find no faults at all in the TPS wiring.

I'm stumped.
 

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LT. is that a new OEM TPS ? Set at .528 VDC and then .660 VDC with the flow 'D' screw ?
 

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Discussion Starter · #26 ·
Yes, the one you recommended from Amazon. I am having a difficult time getting it to stay at exactly .528. I'll have it exact, then by the time I get the throttle body back in place it's plus or minus .002 volts, but still pretty damn close.
 

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Can you set up the meter on it and very slowly open the throttle to WIDE OPEN THROTTLE (3.6 VDC +)
and make sure it is gaining voltage smoothly with NO jumps forward or backward ?

.002 is very close to the base setting but it must advance smoothly. You still show NO codes, correct ?
 

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Discussion Starter · #28 ·
I've checked the voltage increase from (approximately) 0.660 volts to 3.57 at WOT. The increase is linear and smooth, no apparent "stepping" or drops. I've cleared the codes and it's just plain old 6-1, the "no codes' code...

Bizarre, isn't it? I'm no mechanic, but with everything I've learned, I am leaning to some kind of ECU malfunction. I've approached a few friends locally to see if we can source a spare or borrowed ECU to plug in there and give it a try, ala the Polaris shop manual suggestion. I realize a faulty ECU may throw a 2-3 code, but perhaps there's some other mapping fault within the ECU that doesn't throw any codes?

Once again, I do appreciate your assistance and speedy replies! Happy New Year,
MQ
 

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Lt., you will have to refresh my memory about the fuel pressure....................injectors....... and TBAP sensor & harness . New ? old ? OEM ? Clean TBAP ? Plugs NOT fouled ?
 

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Discussion Starter · #30 ·
Of course, it has been some time.

1) I have a real fuel pressure tester, an Amazon unit as you recommended some time ago. 39psi, plus or minus 0.5, it's rock steady. It's a new fuel pump.
2) TBAP sensor - new Bosch unit
3) TBAP harness - new unit from...I forget, but the one you recommended. It's a very nice, heavy duty unit.
4) CPS sensor harness is new, as the TBAP harness.
5) Injectors...I think they're the OEM units. I've not really looked at them! Maybe it's the logical next step?
6) TBAP is clean, throttle body and boots are clean, plugs are fine. Tops of pistons have a bit of carbon residue, but I think it's from the fresh rebuild, allowing a bit of oil up in the cylinder. Again, I've only got about 10 minutes total run time on this engine.

Thanks!
 

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Sooooooo Lt, the engine would rev normally before the ECM (POWER MODULE under the hood )went bad and was replaced with a NEW one or was it running badly before the ECM fried up ?
 

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Ok, so Lt, it ran flawlessly before the PDM went bad................then it set for a year before you were able to get a new PARTZILLA PDM ? ...............In that year you did nothing else to it before installing the new PDM ?? And what was the condition of the end of the connector for the PDM when you installed the new PDM ?


Did you start it with old fuel in it ?

I know............twenty questions, but I can't see it from here..:unsure:

And you followed the TBAP harness to where it junctions with the TPS and inspected and pulled on it thoroughly ?
 

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Discussion Starter · #34 ·
It DID ran flawlessly before the PDM went bad. It DID set for a year before PARTZILLA delivered the NEW POLARIS OEM PDM. ("Covid" was the reason for the delay...) And you are correct, in that year I did nothing else to it before installing the new PDM. The connector for the PDM had a slightly melted pin at the wire for Stator lead #3. I've tested the stator (it "ohms out" correctly, as per the Polaris manual) and replaced that conector with the one you recommended.


Did you start it with old fuel in it? YES, initially we did, but the fuel tank was subsequently drained, flushed and a new fuel pump installed, as the old pump was not providing steady pressure. Pressure now is exactly 40psi, plus or minus about a half psi, and I'm using a real fuel pressure tester, NOT a tire pressure gauge.

I have rigorously checked every inch of the TPS, TBAP and CPS harnesses, sensor to ECM, and they are all good.

I simply never suspected the PDM as the culprit, as I purchased that ridiculously expensive brand new OEM unit...but maybe it's the problem? I can always take it out and ship to Module Masters for a check...
 

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It would be the first time I have ever heard of a brand new PDM being defective but it does appear there is something wrong with it. Did we ever do a compression test ?
 

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Discussion Starter · #36 ·
I don't have access to a compression tester, but we did do a leak down test. Bear in mind the top end (new cylinder head, pistons, rings, valves, etc.) is brand new, with only about 10 minutes total run time. Both cylinders were leaking down at about 16-18%, only through the rings. I could hear the hissing through the oil dipstick tube. I suspect the rings aren't seated yet. No other leaks, no noise from intake or exhaust valves, no leaks cylinder to cylinder no bubles in the antifreeze.
 

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Discussion Starter · #37 ·
J:

I've sent the PDM to ModuleMasters, and we'll know more in a few days re: if it checks out OK. In the meanwhile, I have a very small problem with a wiring connector I hope you can help me with.

The 2 wire connector to the thermistor, the temperature probe on the left side of the engine block, just below the T-stat housing, is broken. The little clip that holds it in place broke when I tried to release it.

I know I can spend $45 and get a whole assembly from OTB, but I'd prefer to simply replace the connector.
Gas Wrist Electric blue Fashion accessory Electrical wiring
Tire Automotive tire Hood Bumper Motor vehicle
find it at Mouser, perhaps you can tell me what type it is, or maybe you know a part number?
 

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Sorry Lt., I have no idea but you may be ale to send a photo the fine people at MOUSER and they may be able to tell you. They have been known to go out of their way......... otherwise .............OTB.

You did say you checked out the STATOR per the service manual ???? A bad one will kill a new PDM.
 
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