1980 Toyota Supra Idle speed Fluctuations

[quote:3ebc6fa9f3="SupraMK1"]I have 1980 Supra MK1 Non Turbo 5 Speed manual with about 69K on rebuilt engine. Car Just passed the smog test last week in CA. Car runs fine in all respect except its spped varies during idle from 800 to 1000RPM. I feel trhe same variations while driving at other speed and any of the gears.
There is another problem which may or may not be related. Once I drove about 100 miles and Car exhause manifold next to the engine got red hot.
I am not loosing any power and engine timing and spark plugs looks good.
Any help will be appreciated.
Thanks[/quote:3ebc6fa9f3]

Could be a fuel pressure problem,coked-up throttle body plate,IACV,TPS,and MAF sensor.Dirty injectors/Oxygen sensor/Vacuum leak/EGR system.

Thanks.
That is too many sensor to start with.
What do you suspect the most and where do I start with?
Hope to get a little better specific guidance to start the process.
Thanks

[quote:8a9c93d352="rasmataz"][quote:8a9c93d352="SupraMK1"]I have 1980 Supra MK1 Non Turbo 5 Speed manual with about 69K on rebuilt engine. Car Just passed the smog test last week in CA. Car runs fine in all respect except its spped varies during idle from 800 to 1000RPM. I feel trhe same variations while driving at other speed and any of the gears.
There is another problem which may or may not be related. Once I drove about 100 miles and Car exhause manifold next to the engine got red hot.
I am not loosing any power and engine timing and spark plugs looks good.
Any help will be appreciated.
Thanks[/quote:8a9c93d352]

Could be a fuel pressure problem,coked-up throttle body plate,IACV,TPS,and MAF sensor.Dirty injectors/Oxygen sensor/Vacuum leak/EGR system.[/quote:8a9c93d352]

[quote:b8cbe88837="SupraMK1"]Thanks.
That is too many sensor to start with.
What do you suspect the most and where do I start with?
Hope to get a little better specific guidance to start the process.
Thanks

[quote:b8cbe88837="rasmataz"][quote:b8cbe88837="SupraMK1"]I have 1980 Supra MK1 Non Turbo 5 Speed manual with about 69K on rebuilt engine. Car Just passed the smog test last week in CA. Car runs fine in all respect except its spped varies during idle from 800 to 1000RPM. I feel trhe same variations while driving at other speed and any of the gears.
There is another problem which may or may not be related. Once I drove about 100 miles and Car exhause manifold next to the engine got red hot.
I am not loosing any power and engine timing and spark plugs looks good.
Any help will be appreciated.
Thanks[/quote:b8cbe88837]

Could be a fuel pressure problem,coked-up throttle body plate,IACV,TPS,and MAF sensor.Dirty injectors/Oxygen sensor/Vacuum leak/EGR system.[/quote:b8cbe88837][/quote:b8cbe88837]

Start with the Idlel Air Control Valve-remove and clean out

i know this 1....there's a hose some where route to the intake with a valve inside...i was stuck at that problemlast time we drop a low miles JDM on the same car..and the idle just wandering everywhere....find all the hose u threw away and start squeezing it!!!!!!..thats a control vac bleeding idler ctrl...
good luck man