justin1889

I purchased a stock 99 FRC (with 47k miles) a couple months ago and lately have noticed when it gets warm it has a very noticable shake at idle. I put in new TR 55's, MSD wires, cleaned the TB and MAF, 2 tanks of lucas, and sea foamed. This past weekend I had a tuner hook it up to his laptop and everything look good. Does anyone have any idea what could be causing this?

C5_Roadster

i have a 99 c5 and it has 58k miles and i have the same problem with mine as well. i didnt do anything but change the plugs but that didnt help at all. i would love to know the fix if anyone has one

thanks

Old Geezer

iTrader: (3)

Intake air leaks.
Unequal cyl pressure[s] Leakdown and comp test done?
Weak coil[s].
Low FP volts at idle?
Dirty injectors.
Bad grounds.
Dirty harness connections.

Back to

mullenh

iTrader: (1)

i hate to guess on the internet. but a 99 can get gummed up around the throttle body from manifold gasses being piped in to meet emmision etc... a good induction flush might help and won't hurt.

Old Geezer

iTrader: (3)

Forgot that idea. We find that is a common problem on the turbo BUICKZ... Called "ring around the collar".

mullenh

iTrader: (1)

see my other post first.
don't suppose you yave had a check engine lite for the pcv valve too?

mullenh

iTrader: (1)

lol. yes it is amazing isn't it. Some people are worried about porting their throttle bodies and having them polished and others have oil and carbon built up around the butterfly and all through the intake.

SSpdDmon

iTrader: (10)

motor mounts???

mullenh

iTrader: (1)

nah they were complaining about a rough idle, not vibration or motor movement

justin1889

I purchased a can of BG 44k to run through the fuel system. Do ya'll think it could be a push rod? How would I go about checking to see if the coils are breaking down?