2000 GT reduced power lately.

[jayrw]

Lately my car just doesn't have the usual response or "pull" when giving it full throttle , I also notice a slightly rough idle along with random "bucking" sensations at lower speeds, I was wondering what are some common areas to look at with these symptoms.. its worth noting Ive owned the car for a little over a year and haven't done any kind of tune ups on it yet (other than change oil & filter every 3,000. changed air filter and recently had trans & rear end fluid changed).

I'm starting to wonder if one of my cylinders is down (fouled plug / bad cop etc.) is it possible to pull wires while the motor is running to check for a missing cylinder?

The car has 70k miles and is all stock except for centerforce df clutch.

On my previous 73 Camaro I would pull plug wires until the engine idle remained the same to pinpoint a fouled plug. wasn't sure if i could do this(safely)with the way these modular motors are setup.

Thanks!

 

[BlownStangGT]

I would think in most cases if you had a misfire on a particular cylinder that you would get a CEL. I know on my wifes old 99, I put new wires on it and one must have touched the header and burnt through and the CEL came on and told me which cylinder it was. So I assume you have no CEL's? Maybe the fuel filter is a little dirty and needs changed? Maybe plugs need changed?

 

[BurningRubber]

Mine misfires at times and I don't get a check engine light for them for some reason.

What you can do is unplug each coil at the cylinder (each cylinder has it's own coil pack, 1 harness that unclips plugging into it) and see if it makes a difference.

Coil packs can go bad after time, sometimes the boots crack causing them to arc and not deliver full spark to the plug. Other times the elements just go bad.

If doing that doesn't change anything, I'd run a compression test to make sure nothing is excessivley low causing the rough running. The heads on these engines have VERY LITTLE spark plug threads, so do this when the engine is stone cold and make sure you don't over tourqe the plugs putting them back in, or you will probably rocket a spark plug out.

 

[02nightmaregt]

possible fuel filter. How many miles are on the car?
EDIT: Nevermind i see now

 

[jayrw]

Thanks for the tips im going to replace the fuel filter first and go from there, is it ok to buy an Autozone branded filter?

 

[2003_GT]

Had the same problems you did, i changed the plugs and the fuel filter and cleaned the injectors and my problems went away, its a cheap fix so id try that first it worked for me

 

[jayrw]

I changed the fuel filter yesterday (I hope autozone brand was OK, that's all they had) and seem to notice a slight improvement but not what I hoped for, the old fuel filter dropped out a bunch of nasty looking sludge when I disconnected it.

Next up ill try replacing the spark plugs, any specific brand I should get?

I also read you can test each COP with a multimeter, I have a multi but not sure whats the normal range of numbers I'm looking for?

Thanks!

 

[02nightmaregt]

For plugs stick with motorcrafts Also try a fuel system cleaner(worth a shot) since your filter was heinous the rest of the system could probably benefit from a cleaning