Alright, everytime I start up the car it shoots straight to 1500rpm to warm up(normal). But as I start driving the car for a minute or so it'll start to surge btwn about 1200 and 500 rpm, a lot of times even stalling at a light or so. What's weird is that sometimes it's perfect with no problems what so ever. When it does idle weird, I'll sometimes throw a code 43(fuel system). Please help me out.
I've swapped IACV's and it's still acts the same.

I have Hondata on a P-08 computer w/Hondata(from a Civic VX I believe). I originally had a GSR ECU, but when I had my motor built by Import Builders, Jeff replaced my ecu without my consent when installing Hondata. I didn't find out until about a month and a half later when I changed out my carpet. I e-mailed him to get my ECU back but he told me it wouldn't make a difference. What are your thoughts about that kind of business?? It left me pretty pist off, considering the fact that I spent A LOT of money there!!
Anyhow, My car is a GSR w/a 2.0 LSVtec. I'm not sure how high of compression because I never got a straight answer, but Lawrence tuned it and said it was considerably higher that 12:1. (I had asked for 11:5, but that's besides the point)
Here's my fuel system:
New fuel filter
Stock fuel pump(I'm thinking this is a culprit, but I'm not sure)
AEM fuel rail, Vortech FPR, RC 310's.
My TB is a ported GSR (coolant hoses bypassed straight to the IACV) Could it be my fast idle valve causing this?
Any help will be greatly appreciated, thanks.

 

I've got a similar ideling prob. Seems like alot of us are having low idling probs. hmmm

 

its the hondata, throw your original ecu back in and watch the car idle much better

 

I'll have to use Hondata on whatever ECU I use. Are you saying that with my GSR ECU w/ Hondata, it'll idle better or are you saying that with my stock ECU(completely stock) will idle better. If you meant the latter, my car will not run properly, my motor is too high compression.

 

I have a similar problem, but mine comes and goes...haven't seen it for 3 weeks, Lawrence doesn't have a clue...and neither do any of the guys here on Honda-Tech, or any other sites that I have used.

Austin

 

with hondata your gonna get bad idling, no matter what

 

I would have to disagree about the "bad idle with a Hondata"

I have a stage 2 on my 12:1 N/A 180whp B16 (even running RC 550cc injectors), and I'll tell you that after being tuned...it runs as smooth as the stock PR3 ECU.
I have no idle problems, whether the motor is cold or hot. I have very smooth and crisp throttle responds, and love the way I can adjust it to suit my needs. I would never use anything but a Hondata.

Who did your tuning? That's the question I'd be asking.

Yell88CRXsi

 

Yeah...okay, if you say so

 

Man, having Hondata is really starting to annoy me. Anyhow, I think my idle issues are temperature related. Anything that I should check?

 

Ya, not trying to be a smart @ss, but go see a certified hondata tuner.

Temperature related? No I don't think so. I last tuned my B16 during 80* temps, and now it's cold as a bitch, and I'm still doing fine. If anyone should be having idle problems it should be me. I'm running a true ram air setup, with a 64mm bored ITR TB, ITR manifold, and RC 550 injectors. so my air intake temps flux drasticlly with the outside air temp.

If you still think that you have a hondata problem, then try this...disconnect the hondata unit from the ECU then start the car. You will be able to drive the car, but it will be in limp mode and rev only to 4000rpm. But all you're really checking here is idle, so start it up, and let it idle till engine warms up. If you still have an idle problem, then your problem is not with the hondata unit. Start looking elsewhere.

A certified hondata tuner check your unit, and maybe even tell you what's the problem. If you do not know of a local hondata tuner, call Hondata, and they can point you to one.

Yell88CRXsi

 

Okay...I have some more information. I have not had this problem for a couple of weeks, however I was able to recreate the problem by accident this evening. Here is what I was doing:

Car had been driven for ~30 minutes where I stopped by the side of the road so that I could finish my phone conversation.

The lights were on and the car was idling at ~750rpm, the idle is very smooth, but with the ES Motor Mount Inserts everything vibrates, so I put my foot on the gas to raise the idle up so that my interior doesn't vibrate apart.

With increasing the idle to 1000rpm I did not have a problem, but if I increased it to 1200rpm the idle surging would begin within 10-20 seconds...if I let off the gas the idle would return to the 750rpm, rock steady idle.

Well since I did it once I decided to see if I could do it again(hell I was finishing my phone call, so who knew how long I would be there), sure enough it would start surging again....anybody have a clue?

Thanks,
Austin

 

I see the same problem with my CRX if idle gets to 1500 to 2000 it surges, but otherwise it idles ok, except half the time it idles low. and when I am in the street at say 25 - 35, slow not hard driving I come to a stop sign the car will die.
Same problem with the ECU for the R with S200, but it runs much better with the ITR map than with a EX map (mini-me). But also if I run a stock EX ECU it runs perfect. I am starting to think the conversion harness so I am gonna try to get another one to try.

I read in another post that the a/f may be rich at idle, I will have to check that as well.

 

with hondata allot of bouncing idles are created with the iacv setup in romeditor if the iacv duty is high the motor will fluctuate and with a rich afr it will do it real bad, your afr at idle should be in the 14-15:1 range,

also if its a gsr throttle body they have a thermostaic valve on the bottom of the tb that will cause the motor to do the same thing.

 

There are a few things that will cause this. The first one would be bad tuning on the idle parameters. The Hondata can idle just as good as stock if properly tuned. The second thing would be a sticky thorttle body. And for you to say this happens every now and than I would have to say that is the culprit. A lot of companies will not bore the throttle bodies correctly with the right angle cut on the butterfly casing it to hang up or not close properly which would cause this problem. I would suggest to swap throttle bodies with a stock one and see if the problem goes away. If it does than you know the problem. The third would be a bad idle control motor which on Hondas do tend to go out from time to time. Check all three of these things and it should go away no problem.