900 Issues that have me at a stand still?

[Himark]

So a bit of background I added the turbo to this sled last summer and have yet to ride it. Sled ran fine when I brought it in but now has issues. I actually dropped it off at the dealer 3 weeks ago and am letting him have a crack at it. In its current form it is running stock computer.

PROBLEM:
Starts and idles high (1600) then after extended idle it starts to build RPM on its own to the point of around 3000.


*SYMPTOMS:

1. Starts hard
2. fuel is puking out exhaust rich

I have checked these things..

1. Fuel is 55#
2. Crank seal is good
3. hosed starting fluid all over crank case while running and motor wont sniff it.
4. intake boots are new
5. TPS is set exact with digital wrench

Things I have done that may of effected this:

1. Pulled motor
2. Hot washed and degreased (maybe screwed up injector)
3. Maybe degreasing ****ed ECM???
4. cut and spliced fuel return line (air possible??) i doubt it but ???

Dealer has a trade in 900 that he is going to rob the ECM from next and try it but I thought I would throw this out to you guys for any suggestions since I feel exhausted on it..

 

[BIGGDAWG]

did you sweep test the tps sensor with an analog meter to check for dead spots?

have you check the wires going to the tps? i just had an issue with mine and my harness was new and i looked at them 10 times and thought they were ok but i took them apart and had a broken wire going to the tp.

Idle creep is usually cause by tp or then engine leaning out

 

[SLDHVN]

the rich condition makes me think det sensor is wierd, but with the high idle that doesnt make sense

 

[Himark]

did you sweep test the tps sensor with an analog meter to check for dead spots?

have you check the wires going to the tps? i just had an issue with mine and my harness was new and i looked at them 10 times and thought they were ok but i took them apart and had a broken wire going to the tp.

Idle creep is usually cause by tp or then engine leaning out

yes did a sweep with a old analog meter on just the tps then did one with the digital wrench also and it charted fine.

 

[IceCap]

Temp and TPS tell the computer what fuel amount to inject into the engine.

If your rich and not running properly then I would suspect these.

The TPS sensor can function intermittently..... some time heat will effect there consistent operation.

The harness can also cause intermittent symtoms

 

[Super Dave3]

Where did you install the temp sensor that was in the stock air intake? If you installed it in your boost box this could be your problem. On my 900 turbo I put the sensor in a small balloon to keep it dry and zip tied to the hood harness.

 

[diamonddave]

Throw a new TPS and a new Connector on there.

When we're setting up and adjusting these TPS', we're NOT simulating real world conditions. We're adjusting them most likely on the work bench maybe even lucky enough to check voltage at idle with the DW. Now take into account the excessive motor shaking in these things, I feel, is taking these pontentiometers and hammering the piss out of the internals.

Funny thing, over the last 10-15 years in the automotive world, I replace 10 Diesel Truck TPS' to 1 Gas Engine TPS. When the OE's replaced the TPS with the APPS, (accelerator pedal postion sensor) the problem virtually disapeared. The common theme here is engine shakin.

So, take into account the excessive vibration of the 9 and the poor quality wiring/connector, and it's easy to see why these things are problematic. Depending on which wire breaks in the connector, that in itself can cause TPS failure.

When EricBigBore and I were chasing his problem last year, 2 different dealers had checked the TPS and it's adjustment. I verified the adjustment and performed sweep tests and would've bet a half rack the sensor was good.

It wasn't.

This was AFTER we had found the TPS connector to have a broken wire, (ground signal wire) and had already replaced the connector. In fact, he had replaced the entire wiring harness.

I talked Eric into replacing it anyway because at this point in time for him, what did he have to loose? He had spent thousands of dollars chasing this problem and was ready to part the sled out.

I keep a brand new spare TPS and TPS connector in my tool box. That's how convinced I am of issues with them.

 

[guidoxpress]

wow...GREAT inputs in here...

i would have to agree with them all in there own way...i am convinced myslef its one of the three issues discussed in here already..

--new TPS
--new TPS harness
--check, verify, re-position,replace air temp sensor

i had a similar (but not as drastic as yours) irractic idle and it was the TPS harness

 

[2poor]

I have a few questions. what year are you working with and whos controller have you put on to run the turbo.
If you are running a 06 900 then you have the fuel pressure set way to low plus it is hard starting. My 06 was doing the same thing when I started out run it back up to 80psi to start with that will give you a good spray pattern again. Then if you are running a attutide controller which wires do you have it pluged on. Need to put them on the bottom injectors not the top ones also when you have the tank back take the controller out and see how it runs. If it clears up then you have something going on with the controller.

One more thing there is a differant controller out there that I have put on that the product supplier ask not to let out. There is two of us out there that are running them on a 06 900 and they seam to work very well. If you are the other person that is running that controller give me a IM and we can talk.

 

[jskattum606]

As for the Air sensor. I shouldnt matter. I have mine just screwed into the charge box as it is in the stock air box(sealed of course). That sucks, work on it all year and not to be able to ride it this winter yet. Good luck

 

[Himark]

2poor..

Mine is a 05 so just 1 pair of injectors.

It is Dereks controller and the first thing I did was unplug it all and hook up stock and has same symptoms. Fuel preasure is set as factory settings right now just trying to eliminate variables until problems is isolated.


The air box sensor shouldnt matter either specially since running it with naturally asperated air with no charge tube hooked to it. But I will try anything right now.

 

[sloan188]

Any other symptons? Do you notice any low end power loss?

 

[sledhead Ed]

If you have raw fuel coming out the pipe you might have an injector that the pintle isn't closing all the way and just dumping all the time the pump is running. Just something else to look for.

 

[Himark]

Sorry still no updates.

Sled has been at the dealer for 3 weeks now and he has not found anything yet.

 

[spike10]

I had some of the same problems. Non-turbo though. Broken ground wire (black) to the TPS sensor. Wire was broken but not the casing. If you unplug the temp sensor plug and check the continuity between it and TPS then wiggle the harness you might find a problem.

 

[jskattum606]

I was wrong. The air tmp sensor is supposed to be zip tied under the hood somewhere. I have a check engine light at WOT and i think this is the problem.

 

[guidoxpress]

Tim,

any progress sir??

hope you get this bad boy on the snow this winter!!!