Good day all.

After fixing the 2006 Sportsman 800, of course, the 2007 X2 500 decides to give fits.

Symptoms: Bought used many moons ago and has performed well for us. 11,000 miles on it – it gets a workout on the ranch, but is also tended to yearly on maintenance. Prior to troubleshooting, good start/idle, but would bog on full throttle, back off a bit and it’d be fine. Then started to bog at low throttle, not hold, hesitate, no power period, but didn’t die.

Trouble codes shown were 42 (temp sensor H/L), 41 (air sensor H/L), 22 (TPS H/L), 45 (MAP H/L), 47 (IAC H/L), 51 (Injector H/L). Have not been able to clear codes by disconnecting battery leads and touching together like on 2006 800.

What I have done:

- Cleaned ground points thoroughly.

- Air intake connections secure to manifold.

- ECT - replaced as was showing 31.5Ω vs. 37.3-39.2 Ω. Cable continuity to ECU good.

- Fuel Pump/Filter(s) – continuity cross check - hard to as goes through SSCB#2, but did disconnect at injector, turned over key, fuel pumps. Removed injector and fuel sprays just fine, though not “hard mist”. Pulled fuel pump out of tank and removed internal 30 micron filter. Replaced inline 10 micron filter (nasty).

- IAT – replaced as was showing 1.824 Ω vs. 2.45 Ω. Cable continuity to ECU good.

- Injector – replaced while I was in there – showed 12.0 Ω with cable continuity to ECU good.

- IAC – cross checked sensor/cable, all showed good and within spec.

- TPS – Did not replace. Pin 1-2 throttle closed showed 4.45K Ω vs. 4k Ω spec, open showed 820k Ω vs. 950K Ω spec.. All continuity check to ECU good. Did not do voltage test due to factory paint marks still in place. Does not feel like a TPS issue that I had on the 800.

- MAP – replaced with new, continuity check good.

- Spark plug – replaced with new/proper gap. Good spark when out of hole.

- CPS – existing and was 187 Ω with continuity good to ECU. Have NOT pulled cover to check gap

- Throttle stop screw – have NOT touched ever.

Current Symptoms: It’s still sitting in the shop, torn down for trouble shooting. Will start, but will not idle. If slow RPM’s below 3000, will die. However, now and again, it might get down to idle, but drop low (below 1000) and die. Have backfire out air intake as well as exhaust when below 2000-2500 rpm and then dies or tries to catch itself right before it dies. When pulled plug, sooty (incomplete combustion/black sooty, thus rich).

Running out of options to troubleshoot. Fuel/Air/Spark…all in sync is what it needs, but isn’t getting it. Noted that at higher RPM it “lopes” a bit, not bad, but does, then when backoff throttle, dies and backfires. PCM? ECU? Bad Fuel Pump? Can’t check fuel pressure w/out cutting line to get in a “T” for a gauge.

Thoughts on this one before I try a new fuel pump/ECU/PCM? Getting close to throwing in the towel and taking it to the dealer. Unfortunately, our local Polaris “won’t work on things older than 2010-12” (which is crap IMHO), thus will have to take it to the Arctic Cat/Kawasaki guys.

Any input would be appreciated.
SDman

 

Update - remembered last night when I ran it, I cross checked the CPS after and it was flakey - ohms, then no ohms. Disconnect, reconnect - different ohm reading, then nothing. Disconnect, reconnect - different ohm reading, then nothing.

This morning I checked it, before running it and was steady 187 ohms. I did check the CPS gap - 0.035 (0.015-0.047 spec), thus figured good.

This afternooon when I ran it (cold engine), it wanted to be "nice" then did it's normal poor behavior, backfire etc. I disconnected the CPS and again noted ohms/no ohoms. Reconnect and different ohms, then no ohms.

Sensor going bad when things heat up causing timing issues, thus misfires?

Thoughts?

SDman

 

I don't normally work on Polaris but I assume the CPS is the trigger coil for the spark timing (and other things). I have had a few go bad, but work OK when cold on Yams, Suzukis and Hondas, older stuff with carbs, so easier to pin point faults. If the coil really does alter regarding ohms, it could be that.

Trouble is, a temp sensor reading cold when the engine is hot can overfuel and won't throw a code unless the sensor is totally shorted or open circuit. Fuel pump not producing enough pressure can cause faults. Dealers can and do, go in for substitution, they have the parts and can put them back on the shelf if trying them doesn't cure the fault. Buying parts that you don't need works out very expensive. Are you beginning to wish your machine had a carb?

 

Shouldnt have to cut line there are connecters at fuel rail or fuel tank to check fuel pressure would be my next test for sure if you dont have gauge pull pump out of tank with it still plumb in set pump in bowl of gas that turn switch on watch for crack line or regulator leaking please be very careful

 

Merryman,
Yes, the CPS is a trigger coil and should be reading steady ohms at a minimum. As it stands, after I have run it, it will read say 165, then blank, reconnect meter and then 134, then blank, wash, rinse repeat, thus thinking that is culprit. When cold, steady 187 ohms.

As for engine temp sensor (ECT) - replaced it as readings were certainly off from "STD".

Fuel pump - not 100% sold on that is the issue, thus trigger coil (CPS) first, then will evaluate if cut in a T in the line for the pressure check.

As for Carb vs EFI.....Carbs can be just as tempermental IMHO (tis on my 55 *****'s Wagon and 55 *****'s PU) and with the dust/dirt/grass etc. we get into don't know if would be better or just another battle.

Appreciate the input.

SDman

 

Papa,

Yup, seen the connectors to the injector as well as out of tank - just don't have the right "ends" on hand to make a spool piece for the pressure gauge to cross check, but that is a good idea vs. creating another leak point. Will have to see what I can scrounge up.

And yes, pulling it out of the tank and cross checking it on the bench...not liking that option, but it is an option.

SDman

 

Update:

Replaced fuel pump, crankshaft position sensor and TPS - No bueno. Still won't hold running/idle below 4500-5000 RPM and then dies and backfires out exhaust/intake.

Have check numerous times for vac leak via spraying carb cleaner downstream of air intake and no leaks.

Anyone have any thoughts? Guess the only thing I have not done/changed is the IAC (it checked out okay via ohms).

 

Don't think you mention changing the ECU. Hate to write it but that could be your problem. As I wrote above, dealers can do all that substitution and it not actually cost anything, other than time, as they can put the parts back on the shelf. This must have cost you a fortune, and still no answer.

You did check compression, valve timing etc? I recently "pratted about" with a Suzuki 500 KQ, looking down the intake I could see it wasn't squirting fuel properly, so went through the EFI system, took hours and all OK. Finally wondered what actually tells the injector when to squirt, has to be the vac sensor, so was there any vacuum? Checked compression and very low, so no compression, no suck, so no injection. Turned out the bike had NO coolant due to a weeping radiator and had seized on the piston, then freed off. Owner had either not noticed, or ignored, the leak and the warning lights for the engine, until it stopped.

 

Check camshaft