Hello everyone. I am having an issue that I hope to havesolved soon. I know idle issues have been posted before, but I feel that this is a unique problem as I have gone through forum after forum. If I am wrong, and you know where to locate this issue, please clue me in.

99 civic cx
Obd1 H22A with B18B1 transmission.
Converted obd2b to obd1 and everything has been properly pinned (except for the IAB).
Engine is running strong and all is well until the airconditioning comes into the mix.
Idle has been set, and there are no vacuum leaks. Whenthe a/c kicks in, all is still fine until I rev and let it drop back down. Thiswill also happen when I am driving and shift back to neutral. The idle will dipway down to almost a stall. The engine will eventually recover and the idlewill sit normal until I do either of those again. This will repeat and sometimestall. When driving, it is not an issue. This is the only mystery/problem Ihave left.
Here is what I have done so far:
*Changed the ignition from internal coil, to external MSD.
*new IACV
*remanufactured a/c compressor
*deleted FITV and has not posed an issue so far.
*remanufactured alternator (which has been tested forproper voltage) *map sensor (junkyard part, but improved engine performancewhen a/c is not engaged) I was using the old D16Y7 map, which made it run alittle odd, but not bad.
*new fuel pump (99 civic si)
*ELD (junkyard part that didn't change anything).
*I have blocked off the EGR (which throws a code on theP13 ecu, but otherwise hasn't affected anything).
*code for o2 sensor heater. Not presenting a problem...I don't think.







So that is the meat of it. I really hope that there is ananswer somewhere out there. It is hot out here in Virginia beach, and I wouldlike my a/c.

 

So are you running a P13 ecu, or a chipped/ tuned setup of some kind?

I would lean towards the ELD as my first thought, but if it has been replaced with no change, maybe not.

How many grounds on the engine, and have you cleaned the contact points on both engine and chassis well?

I may open up my tuning laptop today to check, but I believe that there is an area where there is ability to adjust fuel trim when a/c is activated, at least for Hondata.

 

Snowbordboy. Thank you for your response. Right now I am running the P13. I have a chipped P28, but took it out because it has the o2 sensor deleted and causes the engine to run rich, which gives horrible gas milage. I am having a hard time finding anyone to add it back on with crome. Know anyone?
I'll have to verify that ELD is good. After replacing it, the engine seems to respond faster when I turn the headlights on, so I assume it was an improvement.
There are 4 ground points. I have not cleaned them, but I will do that tonight. I added a ground to the compressor yesterday, but that didn't help.
As of now, I haven't found a reason to justify dropping $ on Hondata. It would be nice though.

 

Try resetting your base idle. It's possible you got a vacuum hose wrong. I'm curious if it acts up when its throwing the egr code

 

I'll do that tonight. Here are the results from where I worked on it last night.

I had the shop recover the refrigerant from the system last night and took it home to start troubleshooting. I vacuumed the system down, but my HIGH side needle wouldn't reach the peg on the gauge. It did read below 0, and the low side held 28hg. I closed the manifold and left it for 20 minutes. No change in pressures. Could the high side be clogged? I was going to disconnect the fittings to the evaporator and try to blow compressed air through it to see if it flows freely. Then vacuum it back down.

If the needle doesn't hit the peg on the high side, does that mean anything specific? Could there be a blockage?

 

I suppose its possible that the expansion valve is bad and its causing stress on the engine when the compressor tries to push the refridgerant through but I can't remember hearing it happening before.

If there is a blockage its likely at the expansion valve, assuming the compressor has never froze up. You would replace the expansion valve and receiver, add a half ounce of pag oil to the system, vacuum it down for a half hour, and if its not leaking, recharge it to spec.