Krazxyglue12

i have a 93 3.0 automatic and when i'm stopped in drive sometimes i get this skip in the engine. its very spuratic and doesn't follow a pattern or anything. the tach doesn't move when it does it all that happens is a little shake throught the vehicle. anyone have anything similiar happen to them? thanks

rimpainter.com

Sounds like a miss. Take a dollar bill and hold it up to the exhaust during idle. It will pop the exhaust, confirming your intuition.

If that is the case, I would look to the ignition system. Plugs, wires, cap, rotor. Check them all.

humanoid

could be clogged injectors as well, not sure if the 3.slow has them

rimpainter.com

If it is injectors, you will get a surge when you let off the gas while driving.

Be sure to let us know what you find out.

EWAYota

how in the world did somebody figure that trick out? and what do you mean it will pop the exhaust?

humanoid

I think what he means is that it will pop the dollar bill, not the exhaust.

DravisAR

So its not dropping or raising the revs at all? Just vibrating? Does the car lurch or move at all?

I was thinking maybe something with the brake system....I used to have an old automatic integra that was testy...id let off the brakes a little at a light without noticing it, and the brakes would cause a weird (and much too strong) vibration through the car...it turned out to be something wrong with my calipers and pads...replaced the pads and their shims and all was well.

Just a suggestion. Id try the "dollar bill" trick to pin it on the motor, although ive always found a hand works just as well

EWAYota

that would make a little more sense, thanks

Krazxyglue12

i've payed more attention to it and noticed that it only happens when im in gear . it only happens when the engine is warm and right before it does it i can hear a click coming from the dash area it almost sounds like something is telling it to kick down but it just skips and i feel a small shake in the vehicle. what confuses me is that its very smooth as long as its not idling in gear. maybe this will help more thanks

rimpainter.com

So something is switching on or off and immediately (in gear) you get an idle flux?

Billf6531

Do you have the A/C or defroster on when this occurs? If so, it could be the clutch on the A/C kicking in, and what you feel is the engine idle speed compensating for the extra load.

kimchee

heres a question....if you are consistently missing does the unburnt fuel hit the o2 sensor and tell the ecu its running too rich?

does it then lean out the mixture and fight a constant battle trying to correct itself?

might this cause pinging?