Desperate Idle Problem

[tom q]

After replacing my plugs and wires, my idle became rough at 500 rpm down to stall and got code P060 (misfire cylinder 6). Did a search and cleaned my throttle body. I removed the TB and sure it was dirty. RPM went up to 600 and no more stalling but still rough that causes the car to shudder when I approach stop. I thought it was the coil so I replaced it too.

Cleaned my MAS, 3 bottles of lucas injector cleaner, seafoamed and still the same. Did a spark test on coil 6 and tested good. Replaced wire and plug on cylinder 6. I have good power and no acceleration lag. Rough idle goes away at 1000 but my CEL will blink at 1500 rpm.

Desperately seeking help.

 

[Tbowdre]

wish i could hep you!... I ended up here because of the same problem

 

[z0lt3c]

Do you mean P0306 and MAF ? If you have replaced plugs, wire and coil, the next suspect would be the fuel injector. I know you stated you used injector cleaner and seafoam but that doesn't eliminate a faulty injector. Have you tried using a data logger to see what else is going on when the idle turns rough?

 

[Rivieraracing]

Why not put your old wires back on and see if the problem goes away since the problem happened after you changed wires? Could have gotten a few bad ones and it's only throwing the one code!

 

[tom q]

I replaced the plugs and wires with the original..still the same. I hear a ticking sound coming from the back. Could that be a bad fuel pump? How do check for data while idle? Upon acceleration, my CEL would blink (misfiring) especially when the road is uneven. The plug on cylinder 6 is white. Does that mean it is burning but fuel is not sufficient?

 

[eshardball]

White plug is usually a sign of a lean condition or ignition timing too far advanced.

 

[JonnyTahoe]

You removed the entire throttle body just to clean it? I'd take it easy on the injector cleaner. I have never used any.

 

[livingez_123]

try a throttle relearn, it fixes a bunch of issues.

Here's how you do it:
- Get in the truck shut the doors buckle the seat belt.
- put the key in the ignition and turn it to the on position ( do not turn it over)
- press the pedal down as quick as possible and hold it to the floor
- turn the key to the off position
- wait a few seconds then, release the pedal.

 

[Alisha]

This happened on my 99 Tahoe last year! It was my cap/rotor. Replaced with after market Delphi and cleared it up... For about 2 months when it happened again. Had a funny feeling it was the same issue with the cap/rotor. Bought AC Delco cap/rotor and haven't had an issue since and it's been a year. I've found in the 15 years I've owned my Tahoe it just prefers mostly AC Delco. I can buy little things aftermarket but as far as fuel and spark it only likes AC Delco.

 

[tom q]

Did the suggestions above but the car still shakes at idle. Blinking CEL is now more frequent. I removed the TB and cleaned it with a toothbrush but I was careful not to open the butterfly. Switched coils and plugs, still the same. I sprayed the intake with a carb cleaner on idle to see if there are leaks. No change.

If the plugs are lean, what could be the cause. Can I clean my injector? Can anyone post a thread of how to remove the injectors?

Thanks for all your suggestions.