i have a 91 RS, auto. and its starting to act funny lately. when im sitting at idle the car jerks slightly. it doesn't do it at a steady rate. when it does it my RPMs drop barley..hopeully fuel filter? any ideas would help. thanks

 

Donno... But ill bump ya ^

 

make sure your plugs and wires, cap and rotor are in good shape or you may need a good tune up and check your timing for possible slipage


mike

 

are you talking about the idle surging? I think that's normal.

 

Assuming its an LO3, these engines are known for their slight vibration at idle, its even posted in the owner's manual. So any slight rpm movement is OK.

However, if you can't remember the last time you got a complete tune-up, getting one now certainly won't hurt.

 

I was having this problem this past summer. New plugs, wires, PCV valve, fuel filter and it cleared right up---just in time for me to decide I want an LT1

 

Sounds kind of like when my Coolant temp sensor went out. Might want to check that. Also, is your EGR in good shape?

 

one thing to check that most people don't think of is making sure all your spark plugs are tight in the holes. iron heads when they heat cycle expand and contract a lot, especially under "spirited" driving that creates a little extra engien temp. this can cause plugs to back out a little and completely ruin your air/fuel mixture 1 cyl at a time and cause a stumble and a little power loss.


later
tim

 

Wow, never thought of that - not a bad suggestion...

 

thanks. so far i have used some fuel injection cleaner and replaced the PCV valve..no change. next im going to replace the fuel filter and check the spark plugs. the whole spark plug thing would make sense because i THINK all of this crap started when i was replacing the spark plugs but when i realized that i couldn't get to the last one on the pass. side i put them back in ( only got to 3 of them). the car does feel like it has lost some power and there is vibration when i get down on the gas and more vibration at idle.

 

it is funny. it is the kind of thing you learn at the track when the car is runnign like crap adn you go to check the plugs anbd unscrew a few of them by hand i felt like a jack *** for the rest of the day

later
tim

 

Well, it IS possible to change all plugs w/o lifting car (had to do it, when car wouldnt start...), but it is anything but fun...You should have vertually zero porblems changing all the plugs if you jack the car up.

 

No fun at all, I agree but possible. Easier if you find a kid with small hands and he can get in there with the wrench.

 

why does everyone talk about how hard the plugs are to get to? i thought it was pretty easy actually just put the car on ramps, just used a socket no swivels or anything and i got them all