Ok, here's the deal. Got a d16z6 that I pulled out of my del sol Si and slapped in my Del sol s (basically the same as a 5th gen dx...) So, I never noticed it on the Si (since it was an auto, yes del sol Si's came in auto too), but now it's revving up to 3K when it's cold. ONLY when it's cold. Not throwing any codes. I replaced all the vaccum lines with ones off the d15 since I knew they were good. Replaced the PCV valve, also checked the gaskets on the TB and the EACV. Then I took what I'm assuming is the cold idle valve (the little white sensor from the very back of the intake manifold) off of the d15 and plugged it into the harness. I assumed that it would just use the ambient air for a reference, and it would work since the ambient air is the same temp as the air going into the intake when cold. NOTHING has worked. So, still holds at 3K when I start it, and then revs slightly as it's warming up. Once the engine is warm, it's fine... I'm stumped. The ONLY thing I can think of now is the gsket for the intake manifold. Any help, or suggestions, are GREATLY appreciated.

 

Are you using the P28?

 

yeah, I'm using the p28, the z6 engine harness too...

 

Both my dad and my old roommate from college have '89 Accords, and they both do exactly what you're talking about...I'm curious what causes it. Hopefully someone can help.

 

ecu has a built in choke? sounds like the choke is working wrong, but not sure how to fix it.

 

It doesn't have a built in choke. Well... Sort of... It uses the air temp inside the intake manifold, and makes it run rich until it's up to temp. Lower chance of detonation. But still, no one knows?

 

It's weird that the idle is normal after it warms up. Usually with a vacuum leak it will fluctuate.

 

bad gas? :dunno:

 

I've been running 93 octane thinking I could clean out the system, but that didn't help. I'm thining it's got to be the intake manifold gasket. Once it heats up, it could close the gap...

 

honestly you know more than 99% of the people on this board, im not really sure what you hoped to gain with this thread.