Jmx305

Hey guys! First of all, I know that there are a million threads about idle problems but I'd search and tried just about everything everyone says, but I can't seem to fix my problem. I feel like I'd done everything. Ok so my problem is that once the car is warmed up, I start having Idle surges roughly between 1100 to 1600 RPM and then randomly it will stop and idle normal at times. I have no CEL light, I'd replace the ECT sensor and bled the coolant, new IACV and PCV valve, but nothing. No vacumm leaks, now I will say that whenever I'm driving and I'm getting close to let's say a light and I let off the throttle, throw the car in neutral the revs will drop to 850 or so then they'll stay around 1500 2000 until I come to a complete stop, the car has always done this but not the idle surges. Now the car that I have is a 98 INTEGRA LS shell with a 96 spec b18c type R engine and Gsr tranny. Internally stock just velocity stack, headers, exhaust, and a chipped p28. I would say my throttle body is not stock because it's 68mm and as far as I know the ITR were 66mm, also I bought the swap with that throttle body. What I haven't checked is the calibration of the TPS sensor but there's defetnetly no vacumm leaks any where. If I unplug the iacv while it's surging the idle drops to about 750 800 RPMS and I get a CEL light. Any ideas or thoughts? Thanks again and hope you guys can help me out. One last thing I wanna say. I'd had the exact same set up on a 92 hatch and it did the same at times and for a long time the idle was mostly normal except the part where it kinda gets stuck when I let off the throttle getting to a light.

v4lu3s

I would dig up an integra type r service manual and see what rpm the base idle should be at. I suspect that your base idle is set too high, i THINK the type r base idle (with iacv unplugged and engine warm) should be 650 or so.

Jakejjohns

Can you take a picture of your throttle body? Some hondas have a fast idle valve that can be adjusted that could cause this complaint.

v4lu3s

Some do have one and very occasionally the brass plate needs to be taken off and the white piece screwed back in. But you aren't using a stock throttle body (62mm at throttle plate) and i have never seen an aftermarket one that has a FITV. I have always bypassed the FITV with a block offn plate since i rarely see aur temps below mid 20s

If your base idle is not correct your ecu cannot adjust idle under load correctly. As best i can determine base idle should be about 650rpm on a type r engine. If you are at 750 that could easily be a problem....also if your ecu chip was tuned with Crome that could also possibly beva factor.

Jmx305

I know I don't have a FITV. Type R engines don't have one. How would I set up my base idle? I do believe my ecu was tune using crome. I don't know much about ecu and chips. Why would that be a factor?