buzlink

I think that my car may be running rich.
If I drive it for 30 minutes or more in warmer weather, the idle and engine firing starts to act funny. If you turn the car off and come back to within a short period the car seems as it doesn't want to run in lower gearing and at idle. Also driving at 20MPH in 1st and 2nd the car misfires really badly. Also in 5th at highway speeds the car will misfire slightly if traveling up a hill. The car never has up and down idling. The ideling acts as the car doesn’t want to run, or the engine is not firing as normal.

I have pitch-black exhaust residue on my tailpipe and back bumper.

How does one diagnose a car running rich? What causes the car to run rich?
What needs fixing? Do the above symptoms sound like another problem I should look into?

Thanks

Kabooki

check timing, replace dist. cap,rotor. sparkplugs/wires (basic tune up) and check air filter would be a good starting point

ReVenGe

ok.... i may sound crazy..... but i never realy payed attention.... but isnt there like a little nipple that you turn on the intake to change that? or is that the idle?

buzlink

My dad is thinking its the MAP or O2 sensor.


I think that is the idle adjustment screw. Not sure.

Running925

new spark plugs!

ngk only!

buzlink

Has had new spark plugs as of recent.

bambbrose

what brand? did the misfiring occur before or after changing spark plugs?

Wharbone

I'd check your timing and also see if your timing belt jumped a tooth.

When you replaced your spark plugs, did you do a full tune up (plugs, wires, cap, and rotor)?

buzlink

After changing spark plugs I did not have any problems. It has been a few months since the spark plugs were replaced. NGK spark plugs.

I don't think it’s the timing. The car runs normal and starts up fine with small runs around town. The car only acts up after driving for 30mins or more.

No I did not do all at the same time. But all items have been replaced within the past year.

Thanks

F22B Prelude

Check Engine Light or No?