trac off light and idle problem

I have been noticing my idle has been a little off lately. (past few months)
sitting at a light i can watch my rpms vary +-100rpm and feel the car surge every so slightly. This is noticeable only to me but its bugging the crap out of me.

I was hoping my "new" 42.5lb injectors would fix this, but today i ran into another (possible unrelated) problem.

Started the car up and the trac off light came on. would not go off if i hit the button either.
Next light i was at i jumped on the gas a little more than usual and the car felt like it was going to stall for a second then took off.
Next light the same thing...

No CEL, no pending code, no misfire under load.
About half way home the light went off.

I am looking up causes for the light in my FSM but does anyone have any suggestions? I was thinking maybe look connection at the firewall connector, but i dont have a diagram for which wire is what anymore.

Matthew

do you think it might be time for a new timing chain? how many miles are on yours? I know that if its stretched it can cause problems...

180k
i replaced the tensioner when i had the motor apart last. chain appeared fine, but that was 15k miles ago.

what about a faulty cam sensor?
another issue i have been having is my car takes up to 6 rotations to start b/c my cam sensor isnt right. No code b/c its only been effecting startup. i need to replace it again (it worked for like 3 days then went bad again) and immediately do a CASE relearn.

That could be alot of different things dude. Just a quick glance at the book says check:

Fuel pressure
O2 sensors
AC clutch
Ignition coil output voltage
ignition wires
plugs
maf connection
vaccum hoses
exhaust

and several other things including Engine Coolant Temperature sensor but I see nothing about the cam sensor.

My vote is ignition miss somewhere.

More than likely its your Gen V supercharger. I'll trade you mine and that should solve your problem.

but if your timing is off,wouldn't it cause the car to run erratically?

Absolutely, but if it was out of time that bad, he would notice running like crap more than just at idle.

That trac off light is providing us a clue here that I'm not sure about.

I just spent a couple of days cleaning out the throttle body and replacing the IAC valve, MAF & TPS sensors on a 99 PA, do you think any of those could be it?

N* throttle body and sensors along with the Gen V at new and still shinny on the inside
IAC, MAF etc are new-ish.

I just replaced the plugs and O2 sensor 2 weeks ago in an attempt to solve the problem (AL104 and denso). wires have less than a year on them and they are acdelo's.

coil pack is suspect b/c i had to replace on a year ago and had to use an autozone one.
car runs fine at WOT, build plenty of boost and is loosing very little power (hard to tell now b/c its 90° outside).

how would an AC clutch cause these problems?

If there is alot of drag on that a/c clutch it would pull down the rpm at idle when the clutch engages. But that doesn't go along with your other clues. That's just what the book says to check for hard starts and hesitation.

Alot of the things book 2 says to check are ignition related so I'm sure there is a way to measure those coil packs to make sure they are working right.

Mr.Riviera wrote:

I have been noticing my idle has been a little off lately. (past few months)
sitting at a light i can watch my rpms vary +-100rpm and feel the car surge every so slightly. This is noticeable only to me but its bugging the crap out of me.

I was hoping my "new" 42.5lb injectors would fix this, but today i ran into another (possible unrelated) problem.

Started the car up and the trac off light came on. would not go off if i hit the button either.
Next light i was at i jumped on the gas a little more than usual and the car felt like it was going to stall for a second then took off.
Next light the same thing...

No CEL, no pending code, no misfire under load.
About half way home the light went off.

I am looking up causes for the light in my FSM but does anyone have any suggestions? I was thinking maybe look connection at the firewall connector, but i dont have a diagram for which wire is what anymore.

Matthew

Please tell me when was the last time you removed and cleaned (Not sprayed in a cleaner or run the BG system but actually removed) the throttle body and the mass air flow sensor?

Albertj

I know the hard cranking is because of the cam sensors 18x reference wire. Its been going on for over a year now because it hasnt gotten worse, set a code or hurt anything.

Its the trac off light that has me confused. Only things i know that can set that light are abs malfunctions and misfires. But i cant find any diagnostic on that in my fsm

Tb was last off the car when i pollished it and installed the genv 6/23/10. 10k miles ago. Maf was removed and cleaned 2 weeks ago when i did the plugs.
thanks for the help so far troubleshooting this.

Man I hope its not a grounding problem somewhere. Hate when that happens.

Two things:

1) fix the cam reference wire; if you dont then the idle will continue to hunt hard.
2) please tell us when you last pulled and cleaned the TB and MAF. dirt buildup in wither will fool the sensors and make the idle hunt.

We'll work on the trac light next. IT would not surprise me to find that the trac control system turns itself off if it cant' get enough information to automatically control throttle; I have to get my fac manuals back to read up on that, that will be a while and by then someone else (Abaddon) will probably have commented. As for trac control, part of how the system works is it reduces throttle as it is pulsing the brakes. You can feel the brake pedal pulsing with the ABS. You can hear the brake pulsing with trac control but not feel the throttle retard with trac control because of how the throttle linkage is set up (you will need to look at it under the hood to see how it is set up, it's kinda complex).

But for right now let's fix that wire and clean the TB and MAF... please...

As for the grounding the critical one to check is probably the one near the ignition module. Look under the module mount for a black wire and follow it; disconenct, clean and reinstall.

Which reminds me, I need to go get a tube of NoAlOx or conductive heat sink grease for this year's ground-cleaning exercises.

Albertj

Mr.Riviera wrote:

Tb was last off the car when i pollished it and installed the genv 6/23/10. 10k miles ago. Maf was removed and cleaned 2 weeks ago when i did the plugs.
thanks for the help so far troubleshooting this.

OK that helps a LOT! no wonder you were not interested in pulling them. 10K miles? unless you are burning 2-cycle gas oil mix there's not much likelihood of crud in there. However, if you reused the old gasket there might be an air leak which for sure will make the idle hunt. Might wanna check that the TB is on right and tight.

Next thing I would do is no kidding fix that reference wire. Also I would (quickly) check the wiring from the crank sensor just to be safe.

Albertj

no gasket for the N* adapter plate to Gen V. its all sealed up with high temp RTV. all vac lines are brand new rubber since the gen V went on.

I just went for a drive/scan and it happened again. i now have a pending code!!! P0341 : cam position sensor range.

LTFT never went +-5 the whole time.

timing seemed pegged at 15* WOT, cant check KR right now with the scanner i was using.

looks like i will be tracing a wire the weekend.

Mr.Riviera wrote:

no gasket for the N* adapter plate to Gen V. its all sealed up with high temp RTV. all vac lines are brand new rubber since the gen V went on.

I just went for a drive/scan and it happened again. i now have a pending code!!! P0341 : cam position sensor range.

LTFT never went +-5 the whole time.

timing seemed pegged at 15* WOT, cant check KR right now with the scanner i was using.

looks like i will be tracing a wire the weekend.

Isn't there some reason that you're not suppsed t use RTV on a gasket coming into contact with fuel?!?!

I don't remember, actually.

Hope you find the problem... I think I am out of ideas.

Albertj

havent heard that, but its good info b/c i use this stuff on most of my gaskets.
http://www.google.com/products/catalog?q=black+rtv&oe=utf-8&rls=org.mozilla:en-US:official&client=firefox-a&um=1&ie=UTF-8&cid=12361395158224888039&sa=X&ei=s7WCTezkK-iH0QHJtOjQCA&ved=0CCAQ8wIwAQ#
Hope i dont have any fuel in the throttle body either. I will give it a good check this weekend and report back. Im running a breather too so there shouldnt be much oil above the LIM either.

new cam sensor has been ordered but im suspecting one of the wires on the firewall has a loose connection/break.

My Rivi has been acting up, similar to what is described. I replaced the IAC cleaned the MAF, PCV, air filter, and some vacuum lines that cracked as I was inspecting them.. I disconnected the battery completely and let it sit.. It ran fine for about 20 minutes until it heated up and started dying on me.. I had to park it on a nearby street so that I can get it towed after work tommorow.. I'm getting ready to order a new fuel pump. Help..



98 riviera 179000 miles

there is a lot of info about my specific problem here:
https://rivperformance.editboard.com/t4703-p0341-camshaft-position-sensor-cam-sensor-timing-chain?highlight=p0341

Not sure if yours is the same or not.

i wonder if these are dying CKPs? Thoughts?

in the meantime here is some "entertainment"

http://www.mightyautoparts.com/pdf/articles/tt64.pdf

Albertj