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Discussion Starter · #1 ·
The machine starts rough and runs but runs poorly, backfires sometimes dies.
With the key on but not running, the base voltage reads 4.14V. The voltage decreases as you throttle up.
The tp sensor, fuel pump and even ECM has been replaced. What to do?
 

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Edge , OEM TPS or EBAY/Amazon knock off ? You could easily have a damaged wire running to the TPS ...


I would be checking the fuel pressure on that NEW PUMP as well if you haven't bypassed the black canister filter above the pump.

If the TBAP harness has not been changed .......it is bad ..
 

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Discussion Starter · #3 ·
Parts are oem. I'll have to go thru the spare parts to determine if the tbap harness was replaced. The voltage for the tps is. 4.14v coming out I'd the ecu, could it be bad?
Can I check the fuel pressure at the end of the fuel rail? Former owner claims new pump put out correct pressure throughout idle to wot
 

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I doubt if the ECU is bad . You have all the symptoms of low fuel pressure and/or a bad TBAP harness.. Yes, a fuel pressure gauge will screw right on to the Schrader (tire) valve at the end of the fuel rail on a 2006 . 39 psi +/- 3 hot and preferably under load.
 

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Discussion Starter · #5 ·
How would a bad new fuel pump cause the voltage to be so high at the tps with the key off?. When running the ranger runs so rich it smokes and fouls the plugs.
4.14V is a far cry from the .528V I should be getting.
 

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Edge, I thought you were talking about 4.14 reference voltage off of a test harness.......................A 2006 700 should read .528 vdc base after fullt closing the throttle plate to zero out and then .660 after adjusting the flow 'D' screw on the throttle body. I think you may not have the procedure correct. Where you are coming up with 4.14 I have no idea. The engine would not even start with a 4>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

A bad TBAP harness will signal the ECU to go full on rich as a safety precaution to protect the engine...... You need to get a service manual and follow the procedures laid out in there ...

I am not talking about a bad pump specifically although it can happen. You could have a bad regulator or like I said earlier the black canister filter above the fuel pump can plug and crack ( all 2006 canister filters have done this ). My 2007 did it.. a 2010 800 Razor here did it.... a 2009 700 Ranger here did it ...........

You could have a combo .TBAP and bad fuel pressure but it will require you to do some work or dump about a grand at the stealership....
 

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Not possible....Not even in Biden Land...
 
  • Haha
Reactions: D. McB.

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Discussion Starter · #9 ·
I'll try replacing the tbap harness next, I'm not seeing one in the spare parts bin that came with the rig. interesting how the voltage going to the tps goes down as you throttle up.
Thanks for the info. Been following the testing procedures as set forth on this forum.
 

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With the black lead from the Volt meter grounded and the red lead going to the yellow wire going to the tps...
Edge, I am telling you............... The engine would NOT START if you had a 4 at idle... You meter must be whacked out.
 

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Discussion Starter · #12 ·
Edge, I am telling you............... The engine would NOT START if you had a 4 at idle... You meter must be whacked out.
I hope your right. But I watched the same voltage being displayed on the previous owners meter.
I'm going to look for a meter that reads lower voltages. If it was .414V that would explain a lot. Lol
 

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Discussion Starter · #13 ·
One more question... I see there was 3 wires going to the fuel pump. Hot, Grnd and a purple wire with white stripe. Any idea what the purple wire went to or what it's for?
 

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One more question... I see there was 3 wires going to the fuel pump. Hot, Grnd and a purple wire with white stripe. Any idea what the purple wire went to or what it's for?
Normally, on a 2007 and up the third wire is for the gas gauge. On a 2006 ...........no idea .
 

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You should run the codes and see if anything shows up. They do not always throw a code for TPS & TBAP but it is worth checking..
 

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I get a 61 code
61 is>>>>>>>>>>>>>>>END.. So no code has been thrown but that means>>>>>>>>Notta. POLARIS ECU's are the worst for diagnostics..
 

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And when running at an idle the voltage to the TPS remains about 4.14.
Probe the other TPS wires. Previous owner may have crossed wires while replacing pigtails.
If someone mixed up the wiring you will get irrational readings.
(My used Ranger came with signal wire connected to T-Bap ground!)
 
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