Hey guys, I've been doing tons of work to my 93 accord with an h23a1 in it. I've cleaned my intake manifold, throttle body, did a tune up, replaced all my hoses, and replaced all my fluids. Even after that my car takes about 20-30 mins to start when the motor is cold. Once it gets started there's a popping sound that happens a few times and if I let the idle dip it'll shut off. Also, once it gets warm the idle fluctuates from 1k-2k. Sometimes it even spikes from 1k-3k. Anyone have an idea what this can be?

 

Did you delete your fast idle thermo valve "FITV"? That's like a choke on a lawn mower for our cars. Try recalibrating your throttle positioning sensor "TPS".

Any vacuum leaks?

Is your ignition timing off?

Try cleaning the idle air control valve "IACV".

 

I haven't removed the FITV. To be honest this is my first H series motor so I'm still figuring things out. I cleaned the IACV when I did my tune up. I'm worried my timing may be off because there's a lot of play in the belt. But as far as vacuum leaks I've found nothing. I replaced every hose I could find and clamped them down.

 

Then clean the fitv and see if that helps, its on the TB. Do a timing job, and dont forget to jump the service plug or the ecu will undo what corrections you make. If there is too much play in the belt the auto tensioner may be going out, which H series are notorious for.