I have a 92' Accord Ex and the other day while i was driving my first spark plug broke , the white part on the middle where it connects to the steel of the plug broke loose , so i replaced that spark plug and then my car idles at at low rpm . so i replaced all 4 of them again and my idle keeps on getting lower. it starts from 700 rpm and down to 200 more like 150 rpm and it just keeps going up and down up and down from 700 to 200 ...anyone got any ideas why??

 

Grab a couple of cans of carburetor cleaned and clean out the PCV residue from both the Throttle plate and the IACV motor. When gunk builds up around the t'plate it (in effect) closes off the air flow, leaving the IACV* trying to compensate. It can only compansate so much....
*Idle Air Control Valve"

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Help me P Adams or other
90 Accord LX >300Kkm Check Engine light ON. Changed O2 sensor. Light still on. Also Speedometer and odometer not working. Not sure when it stopped but definitely not longer than a week .Not a mechanic had a friend help me. Can we fix it or what ?

 

Derek
Your question i answered on the thread you started elsewhere.

best
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Also when the "Maintaince Required" Turns from green to Yellow what would be the problem for that changing

 

Ive dont that yesterday I Made sure all of it was gone but the idle still jumps up and down

 

I'm beginning to question the Fast Idle Thermo valve and the possibility of a vacuum leak somewhere. You're not experiencing a non-discript hissing from under the hood are you?

FITV - Drivers side
IACV - middle

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Hey Paul,

This compensation from lack of airflow into the IACV, can this harm a car if kept for too long? I'm thinking that crappy fuel mileage would be the only issue.

I have the same idle compensating up and down. For some reason it only happens when the weather gets cold.

Thanks!

 

Other than an unrelyable idle and the loss of gas milage. It won't really hurt anything other than your sanity.

Another thing to look at: the FITV (Fast Idle Thermo Valve) is heated by engine coolant passing beneith it. Check that your system is properly topped off with no air pockets in it.

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I need some help with my 90 Accord LX, automatic. At speeds of about 50MPH it starts to skip real bad and almost sounds like its backfiring. If I hit the accelerator and go faster it’s seems to be ok and if I pull over and let it idle it’s ok. It idles great when I’m parked.

I suspect the problem may be some work I just did. Recently I noticed an oil leak from a part on the front of the engine located just below where the upper radiator hose connects to engine. I don’t know what you call this part but it bolts on to the engine with three bolts, has a electrical connector that must be removed and looks like it has two cylinder type tubes coming out of it. I removed it, replaced the rubber gasket and re-installed it. Would this have anything to do with my current problem?