I'm having a strange problem with the sol, and I need help. I don't know where to start really.. Right after it starts to warm up, and at idle with the car not moving, the engine RPM will drop a down to almost stall and then bounce back up to normal or slightly above. Sometimes it will settle back at normal idle after that, sometimes it will keep bouncing up and down. It doesn't seem to do this all the time, and it's not really repeatable. Resetting the ECU doesn't cure it, and it's been doing this for about 2 months.
I have no CELs, and the engine runs great except for when it settles down to idle at a stoplight,etc. It will usually stop doing this after I've been driving for a while, i.e. the engine gets up to normal operating temp..

It's been doing this since the last valve adjustment, but this may not have anything to do with it..

I'm thinking the IACV may need cleaning, the PCV valve is bad, or the fast idle thermo valve is bad. Again, no CELs at all..

Any suggestions or personal experiences anyone can share? I'm an electronics guy, not a emissions system guy, so I'm new to this kind of stuff..

It's a basically stock 95 B16 del sol by the way, OBD1 and it's a VTEC sol, not a swap.. It doesn't have a history of any other problems.. I'm selling it so I want to get this stupid annoying little problem fixed..

 

First I would check the fast idle valve (make sure the plunger is all the way down and not up) and clean your iacv. Let us know if this works.

 

Cool, thanks..
Sounds like a start, I'll try that this weekend. School sucks..

Anyone else have advice?

 

What probably happened in the white plastic piece in the inside came loose, because it has threads, just tighten it back up and it should get rid of the rpm problem,check the spring tension also, this is the same thing that happened to a friend of mines car, tightened it back up and got rid of the idle probelm....

 

what white plastic piece? describe..

 

Its attached to the bottom of the throttlebody, has 2 coolant lines connected to it. You will notice on the right side of the valve (it will be the side pointing at you and it is the more round side), there will be 2 small cap screws holding the cap on. pull the cap off and you will see the white plastic plunger with the ring around it. The ring has a notch in it. That is what you tighten.

Go ahead and clean the IAC valve screen though just to be safe.

 

^^same exact thing with my sol

 

I have a new one on the way just in case it's bad. I hate taking pain in the ass stuff apart more than once, not to mention dealing with coolant..

 

how much do u want for the car?

 

bling bling!