I know, I know, do a search. Well, I did.....for hours! I found alot of people that have/had the same prob and alot of suggestions, but noone saying what actually fixed it.
Anyway, here's the prob. I just did a JDM H22a swap and now the idle jumps up and down between 1000 & 1500 RPMs. We had some warm weather today and it seemed to do fine, but started again tonight. When I turned the headlights off, it eventually stopped. I swapped ECUs back to the H23 and it didn't do it.
Here's what I've done so far. I've checked all the vacuum lines and checked for leaks. I purged the cooling system. I reset the computer. I was thinking since it did it again tonight after it cooled down, it might be cooling system/sensor related. I really don't have a clue though.
Any input or solutions would be greatly appreciated. This is the only bug I have left to work out after the swap and I'm sure this will help people in the future too. Thanks.
Keith
BTW: I about wet my pants when I hit VTEC for the first time! Awesome feeling!
Mine did this as well. I had a honda tech wire everything for me and get the motor running well he thought the injectors from the old motor (f22) would work. I knew that they would not and wanted to put them in before they were done but to make a long arse story short. I had the wrong injectors in the car. After they put in vtec injectors all my problems were gone. I also ugraded my plug wires, don't think this was a major factor. You also might want to try cleaning out your cold air idle valve(kinda sounds like your problem). I did this before the new injectors real easy to do. There is a little screen in it that gets clogged up over time. Other than that I am not sure, all I know is my car used to do this and now she runs perfect. Be patient you'll figure it out. Good luck
go read the thread "i need a tps sensor" here in this forum...i have the same problem just cant fix it yet
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Brandon
Captain - my other car has two engines
1993 Prelude Si (JDM H22A with automatic to 5spd Swap) My white 93 Vtec
AIM: Mach30SiR
I had the same problem... I just changed the Fast Idle Control Valve and it went away.. ( t's the thing mounted on the TB directly under it with the two coolant lines running to it..)
i had my idle problem for about 2 months. first thing that i was almost certain it was was the IAC. i ordered a used one from a guy and installed it. the idle was still bouncing. took it to a shop and they ran a diag. and no vacuum leaks and checked tps sensor reading. then i ordered a new radiator since mine was leaking thinking it could be air in the coolant system. that didnt work so finally i took it to a shop and they replaced the IAC again with a new one. the idle problem is gone and its the best thing in the whole world.
Did any of you use the second ECT sensor which is found on USDM engines but not JDM engines? I did, and havent really experienced this problem (my idle was a little funny at first, but I adjusted the screw and set the timing, and now she idles fine).
Originally posted by red92s Did any of you use the second ECT sensor which is found on USDM engines but not JDM engines? I did, and havent really experienced this problem (my idle was a little funny at first, but I adjusted the screw and set the timing, and now she idles fine).
I did, I swapped over the coolant neck too.
Im using my entire h23 harness and dist w/ external coil.
The only wiring differance in my car now is the 2 extra vtec wires, everything else is from the h23, except the injectors anyway.
Thanks everybody for the input. Matt, I used the VTEC injectors that came with the engine and cleaned them, so I don't think thats the prob. I also swapped the coolant neck and used the sensor. My next step was going to be the IAC and the fast idle thermo valve. I took the ones off my H23 today and am going to clean them good and then swap them. If that doesn't work, then I'm back to square one.
Jason, what smog crap is there that is different? I'd like to know, maybe I can swap a couple of things there too.
Anyway, thanks again all! I'll let ya know if the IAC and fast idle valve work.
Well, back to square one!! I finally had some time to work on the car today and changed the IAC and the fast idle valve. No help!
Listen to this and tell me what you all think. I test drove it with the headlights on and when I come to a stop it surges (after it reaches normal operating temp). When I turn the headlights off the idle goes down to where it should be. The problem is worse at night when its cooler outside and same senario with the headlight thing, but takes a little longer to settle after I turn them off. Do you all know what regulates/speeds up the idle when there is an added electrical draw on the engine? Thats the only thing I can think of now. I might call Honda Monday and see if they can help. I'm running out of time on my warranty and if it happens to be a faulty ECU, then I need to call the company I bought it from. Thanks all.
Mine is back to doing the same thing but not as often. when headlights are on it does it when i come to a stop, but if I turn the A/C on it makes it drop a lil and stop surging. but now it does not surge when the headlights are off, unless it gets really hot.
Man I am so pissed about this. I had the same thing going on but took it to a couple of different honda dealerships to have a look at what was wrong and it is not a problem any more. I just can't for the life of me remember what it was that they fixed. I would suggest calling Honda. I am sorry man its been a little while since this was going on with my car. How are your plug wires??? I think I remember them putting bigger wires on and that may have been it??? I will call them to see if they have what they did on my record. Proly wont those bung holers. i will keep trying to remember for you guys. I am angry
I'm using the plug wires that came on the engine, I think they are original. I was going to get a new set anyway, so I'll try that this week. Thanks the help.
It seems like this idle problem is the exact same as mine. they told me to clean my injectors but i told em not to. anways since replacing the IAC didnt work i took it back to the shop and told em what it was doing. he said most likely it is a wire grounded somewhere thats not suppose to be. they are gonna take a lot at it tommorrow so i will keep you updated.
I was thinking about this and thouhgt it might be a good point. I know that one of the things we do when swapping in the JDM is swap fuel rails from your current engine to the JDM. Could the FPR on the JDM be set higher/lower causing incorrect fuel pressure.
I think I found where the problem is. Just not sure how to fix it yet. They were on to something about the ground wire. There is a ground wire coming off the left (driver's) side of the engine and bolted to the strut tower. I took it loose while the car was surging and the idle smoothed out perfectly. I put it back on and it started surging again. Took it off; stopped, put it on; surge......
Something is wrong with the wiring for sure. The ground wire sparked alot when I touched it to the body and caused the engine to pop through the intake. I always thought ground wires weren't supposed to have any draw or power to them.
My mechanic is off today, so I'll have to catch him tomorrow or sometime to figure this out. If anyone knows why this is please let me know. We're getting closer!!
Zimmlude-- I tried the FPR this morning and it didn't change anything. Thanks for the thought though! I appreciate your help!
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