Spitting and rough when engine gets to normal temperature

[Absolute_T]

It all started about 2 weeks ago. The car has no problems starting when cold. The problem is that as soon as the engine got to normal temperature and I stop the engine and leave it for 5-10 minutes, it has problems starting and when the engine runs it runs in a rough way and even stops. From time to time it also backfires while trying to turn the engine on. If I leave the car off for 1 hour it starts without no problems again. The problem with the rough running persists as long as I'm not driving. As soon as I get it to run and drive for about 1 mile it gets better again and then runs normally. All that was when the temperature was still lower.
Yesterday it got less cold and now I have the same problem while driving after 9 miles.
For me it looks like there is 1 of the 6 cylinders that doesn't get the spark. The strange thing is that it only happens when the engine has a certain temperature and not when it's cold.
Any suggestions?

 

[Big Jim M]

Temperature related bad running could be the coil. When the coil runs as it should and when heated up to normal temperature it shorts itself and cannot perform properly.
Big JIm

 

[rurouni20xx]

clean your maf/iacv and see if that helps, could be carbon in the system and just happens to stick with the engine warmed up.

 

[Absolute_T]

Thx. I replaced the ignition coil and it is running smoother. In the beginning that is. Still I have misfires after driving for 7-8 miles. Outside temperature is low again, so I couldn't tell. I have to wait for the temperatures to go up again to be sure about it.

 

[Absolute_T]

Last night I drove home at temperatures below 0. After 12 miles bad ignitions. The rest of the trip was filled with prayers to make it home. Just before getting there the engine stopped while driving.
The coil is replaced. Is there anything else I could check?

 

[Viper Command]

for some reason im thinking its the (EGR valve if equiped) and or the o2 sensors

the best way to find out is to do an OBD-I data log when your driving and its cold out.

 

[Rearanger]

The EGR will only stall engine at idle. A coil affected by heat can cause rough running, back-fires, bucking under load, it'll be (much) worse under load than idle. Does your year have an ECT (Engine Coolant Temp) sensor? If so it could cause rich hot run that will give you idle and run problems? Check plug appearance for rich run. I would also check 02 sensor as suggested. After start-up engine runs open-loop with 02 sensor not in play until warm up to closed-loop. If it's dead now/no start, then check if this is one or more cylinders on electric misfire.

 

[Absolute_T]

I just ran a KOEO and a KOER test on OBD1.
I got:
211 (Two or more successive erratic Profile Ignition Pickup (PIP) pulses occurred, resulting in a possible engine miss or stall.)
538 (Insufficient RPM change during KOER dynamic response test/ Operator error)
536 (Brake On/Off circuit failure / switch not actuated during KOER test)

For 538, I didn't touch the gas pedal during the whole test.
For 536, I know the brake switch near the pedal has to be changed. I already have a new one, but I still have to install it.

211 is what I am trying to find a solution for. I think the 538 is related to it.

I will try a CM test this evening.

 

[Absolute_T]

Just finished trying the CM test. Can't get results now cuz the engine is still warm and after 12 miles it just went off as soon as I was on the parking spot.
I checked under the hood for no reason, but I saw that there was a strap hanging loose from the engine block. Above the one end and in the same line I saw a ring that the strap could fit in. I fixed that and thought it was ok, but the engine still wouldn't start.
At least I fixed the engine's ground strap that was actually getting contact from one of the beams of the car's chassis that it was hanging loose on.

I guess I'll still be stuck on my 211. I'll post the CM codes as soon as I get them.

 

[Absolute_T]

That's it. 211, 536 and 538 is all I got.

 

[Absolute_T]

Ok, here were are. All I got left is a 211 and a 536. I think as soon as I would have changed the break switch at the pedal the 536 will disappear.

 

[Rearanger]

Does your year have a crank angle sensor? I don't think you have confirmed spark or fuel yet?

 

[Absolute_T]

Just to keep everybody posted.
The problem is not from the heating up ignition coil. This morning I had the same problem. I stopped the car and hooked up the older ignition coil that was still cold. Same result.

 

[Absolute_T]

Does your year have a crank angle sensor? I don't think you have confirmed spark or fuel yet?

It should have a crank angle sensor. According to what I found on the internet. Where can I find it under the hood?

 

[Rearanger]

Crank angle sensor is very heat sensitive. They get their signal off the crankshaft pulley so it will be located somewhere around the CS pulley. I don't know if they are go/no go or if it could produce your symptoms, but without a proper signal from the CKS the PCM won't signal the coil pack to fire. I think all you can do is test the resistance at certain temps and compare to spec.