Car 93 CX Hatch
Engine B16A (some mods )
Timing fully retarded, and it still idles high

The engine in my car has had idle problems from the very begining. It would idle around 1200, until I adjusted the valves, then the idle returned to about a grand. (??)

Once the engine is fully warmed, the idle INCREASES, in traffic it has gotten as high as 2400 After cruising for a while the idle DECREASES back to a grand.

My friend knows nothing about cars, he has a 89 Accord which had a similiar problem. He went to a mechanic and the mechanic just told him to put more coolant in there, which he did, and the problem was fixed.

My coolant level is fine...but...I have the stock CX radiator. (I know, I know, Fluidyne is on the way)

Does coolant level affect the idle at all?

 

I'm not an expert at that category but I dont think it would affect it, as long as the engine temp isn't too hot or cold, the coolant wouldn't change the idle... but that's just me using common sense; anybody know the answer for sure??

 

Timing doesn't necessarily directly affect idle speed.

That said, I think you may have a TPS or IACV "glitch".

 

I would check for misrouted vacuum lines and or broken lines. also what was done to the fast idel solenoid on the intake manifold.......?

 

All vacuum lines have been accounted for, and are all connected correctly.

Interesting note about the TPS glitch, I picked up a TB with a new TPS in today, and will be changing it tonight, I'll post the results.

I appreciate the help guys.

 

Well, changed the TB (with the new TPS) and car idles normal now.

Just a quick question though, how does a faulty TPS cause problems with the idle?

 

Fluctuations in voltage readings to the ECU cause changes in air/fuel mixture, so the ECU thinks the throttle is in a position other than closed and tries to work out something with the o2 sensor to get the mixture right, which is unnecessary since the throttle is closed.

I love it when I can nail a problem on the head first try

 

Awesome...thanks stud.