can't figure this idle - Honda Prelude Forum

my project lude · 03-16-2010, 05:34 PM

So I bought my new girl from a repo. The revs were going about 1500 up and down but the engine sounded good and had some good mods on it. Price was right and I bought it. Crazy things after that. They had put a peice of electric tape over the filter for the IACV, one bolt holding in the distributor and the cap, NO oil, and header gasket blown out. So I went through and changed all these things except the gasket (on order), and here is where is gets really weird. I changed the oil on the car and had it on Jack stands. Start the car, while on stands, and the idle is perfect. Lower the car and restart it.....you guessed it, idle returns. The other thing is the engine will not heat up. After driving it for about 15, 20 minutes the engine is still cool enough for you to touch. My first H22 so maybe that is there thing, but I son't think so. I know there is a Lude junkie out there that has seen this before....HELP!!!!!!

commandokock · 03-16-2010, 07:02 PM

maybe im misunderstanding your problem. maybe the gauge doesnt work for the coolant temperature but since a cars engine runs by combustion, im pretty sure your car cant be cold after 20 minutes of driving. what part of the cars engine are you touching? if it was a thermostat issue then id say your car would overheat. it cant stay cold because combustion (fire) is hot, right? my point is its physically impossible for your engine to not heat up while its running.

C4rn4g3 · 03-16-2010, 08:01 PM

I am also confused... try touching the headers.
Is it hot after 20 min of driving?

indylude18 · 03-16-2010, 08:02 PM

Quote:

Originally Posted by commandokock

engine runs by combustion, im pretty sure your car cant be cold after 20 minutes of driving.... it cant stay cold because combustion (fire) is hot, right?

Thank you, for that....

O.P. the idle problem could be any of a number of things. Check this out first.
Idle Problems - Look Here First

As for the temp problem, your thermostat is probably stuck open. Just replace it (~$25) and that part of your problem should be fixed. If you leave it like it is, the ECU will remain in "warm-up mode" and you will get crappy gas milage and no vtec.