Car is a '95 GSR, B18C1 block, JDM B16 head Jackson super, Edelbrock TB, and the cold idle is stable at 1400RPM. As soon as it warms up tho, the idle drops to 1k and continually cycles up to 2k then back to 1, 2, 1, 2, 1, 2, 1...

Each cycle from 1k up and back to 1k takes about 1.5 seconds. I read some erratic idle threads and skunk 2 high idle problem threads here on HT, and all suggested a vacuum leak and/or intake gasket leak. I've checked as much as I could, and did find one poor vac connection (hose went to 2 different sized fittings and was a loose fit on the smaller one so I clamped it but it didn't fix anything noticable).

I've also squirted starting fluid around the intake gasket points and had no increase in RPM. Since it idles fine when cold, I'm thinking it's not a gasket problem or it would be erratic all the time (correct me if I'm wrong, please). I suppose my next step in troubleshooting will be to narrow it down to what the difference is between the cold-start system and normal operating conditions.....I'm new to imports but have been around on the american V8 scene for quite some time. I had similar cold/warm problems in the past w/ a Ford police cruiser and it turned out to be a temperature controlled vac switch which was part of the cold start system (to allow for easier starts of a cold motor). I've been reading up on the systems in the 'teg but don't see anything specifically mentioning cold/warm vac line routing/switches so I'm kinda lost.

My 'teg has an APEXi V-AFC controller but it isn't programmed to do anything whatsoever except change the vtec engagement point (will be dyno-tuning it later since I just bought it last weekend, but wanted to get this annoying idle problem fixed first so I don't sound like a broke ricer every time I stop at a red light). The prior owner said it has a "Jackson Racing FMU" for the supercharger, but from what I see on Jackson's website they don't have their own FMU's....tho some of the boost kits do have hondata boxes. I have no cable or software to connect to any EMU or FMU in the car and haven't even put an eyeball on the actual box yet (was told it is mounted where the passenger side airbag *used* to be...haven't ripped the dash apart yet tho).

I guess I'm turning towards you more experienced folk to point me in the right direction for my best next move in troubleshooting this car. If the guy I bought it from still has his profile up, there is a good description of the car at http://www.cardomain.com/memberpage/799740 (link still worked when I posted this)

Thanks for any advice/pointers!!

 

I would take a look at the Idle Stabilizer Valve. A friend of mine on his LS would do that. I know yours is more performance but they would both cause the same effect?

Any CEL's?

 

will check the Idle Stabilizer Valve (not sure what it is but hopefully it's in the Haynes manual lol). Sounds reasonable. Not sure on CEL's....the light isn't on but I don't know if anything's stored (My toyota auto-clears the codes when probs are fixed so no light means no CEL, but I don't know if the teg is the same way...will check it anyway)

 

Geebus....couldn't find the pigtail to jump the 2 pins to grab any CEL's.....it's nowhere to be found! I did find the ECU box under the front passenger carpet and it looks like a stock unit with a bunch of sharpie writing on it crossed out....like SOHC then VTEC-8000RPM, and a few other faded unreadable crossed out stuff......no serial connection to hook to a laptop which is why I'm guessing it's a stock unit (hodata's have a serial programming plug don't they? Not sure). Anyway, I can't check for CEL's until I buy a diagnostic handheld that'll plug in to the 16 pin harness (provided that didn't disappear as well)!

As for the Idle control valve, I think I found it...2 wire sensor plugged bolted into the supercharger, but haven't removed it to apply voltage and listen for a click yet (it got dark out before I got to that point).

Anyway.....I played around with the APEXi unit and was able to get a stable idle at 1500RPM (cold idle was 2000, not 1400 as I originally stated....was going from memory and sound and I was ummmmm off). I changed the 1st 3 NE ranges on the low cam side to 1000, 1500, and 2000 RPM then entered in a -45 on the 1500 range and that stabilized the idle....but that certainly isn't the right way to do it and I'm not sure what air:fuel ratio it's getting at idle now. I'll find out once I take it in for dyno tuning tho.

Any other suggestions will be appreciated, Tomorrow (Thursday 5-26) I'll be going to talk to 2 different shops to determine which one will get my tuning business, but I'll prolly have to wait for payday before actually giving them the car. I'll drive it to the shops tomorrow so they can stick an eyeball on it, but other than that it'll stay parked until being taken in for tuning. Meanwhile, I'm free to putz around with it to try to get a better idle correction silution than what I've done thus far.

 

Hey EE_Chris, I got your pm (although I didn't see it until I allowed popups here). Since I'm still a trial member tho, I can't reply

When I unplug the IACV (if that is in fact what I unplugged) w/ the motor running and warmed up, the RPM's drop and the motor wants to stall.

 

I am not sure if the edelbrock TB still has the FITV on it (Fast Idle Thermal Valve) or not. I would recommend letting the car warm-up (one or two fan cycles) and take off the intake tube. Feeling around on the TB you will see 2 holes on there (again not sure about the edelbrock TB) one is for the FITV and the other is IACV. Plug the hole you can see (looking straight on to the TB) on the left side with your finger. If the idle drops to normal, then the FITV is the problem. I had this problem on my LS teg and after searching on here for FITV, it had a step by step process on how to fix it.

Just take the little cover off of the FITV on the back side and you will see like a ball plunger type thing and a white washe that has two notches in it. (you might need a mirror to see it). Just spin that washer until it is snug and tight. Hopefully this fixes your problem. It is alot easier to take the TB off to do this, but it can be done on the car. Good luck and let us know if this fixes it.

Oh, if that isn't the problem, it might be the TPS (throttle position sensor). Check the voltage on the red wire with the ignition on and not running. Closed throttle should be around 0.5 volts and WOT should be about 4.5 volts. This is another known culprit of the bouncing idle.

 

I'm kinda new myself, but i have an h22 integra doing the same exact thing, try disconnecting the IAC sensor, i did it and it stopped, but then the car drove funny.
I met this guy that supposely has one at home, the whole IAC and valve thing, so once we change it, i'll let you that might be your same problem.

 

I'll try to find out if it's got FITV on the Edelbrock or not and give that a try. The voltage is correct on the TPS, the V-AFC box in the dash has a throttle sensor readout.

Another thing to note, the car is very rough while driving if the rpm's get below about 2200 or so. It's not that big of a deal most of the time, but trying to keep down with traffic in a 15MPH school zone just plain sucks...I can either leave it in first and have it looking like I'm some moron that forgot how to shift (very loud exhaust, header, race cat, apexi cat-back) or grab second and have it stumble and jerk all to hell. I'm betting that problem will go away once the idle prob is fixed right, but maybe that gives someone an idea of what else to check (in case it isn't the FITV or if the Edelbrock doesn't have one).

 

i heard the map sensor can cause bouncy idle..... ?

 

I pulled the cold air intake and did in fact feel 2 holes inside trhe TB. When holding my finger over one of them (the one on the bottom...which is the left-most), the motor would stall. I also called Edelbrock and am waiting a callback on weather or not it has an FITV. All I see on it is the MAP sensor and the TPS. It also has a fitting on the bottom that coolant runs through, a few vacuum lines (none of which are leaking), and one unconnected fitting which I have no farking clue what it's for (looks like a vacuum line size-wise). I held my finger over the disconnected fitting and felt no suction or pressure. When Edelbrock calls me back I'll ask them what that port is for.

I've been working on other stuff on the car in the mean time, prepping it for the PA inspection (safety and emissions...tho I had a tuner shop tell me not to worry about the emissions and that they would handle it, weather that means they'd tune it to pas or just give me a sticker regardless I'm not sure). The bonehead original owner put a momo steering wheel on it and deiceded to just remove everything horn-related (needed for the PA safety insp) so I fixed that today among a few other lil do-dads between beers. I'm feeling better about the car now at least....for a while I was worried it was a ghetto project car the way some of it was slapped together but it's starting to all seem okay now (except for this damn idle/low RPM prob).

Any of y'all XM subscribers? Fungus 53 crankin' in the background sure makes working on these things more enjoyable! (altho it tends to **** off the neighbors...as does my exhaust...fukem)

 

Oh...one more thing, a dude several posts up asked if there were any CEL's and I couldn't find the damn pigtail to jump it and check (still trying to figure out wtf it went!....had the pass side dash and trim panels removed all over the farking place). I did pull the "backup" fuse for 10 secs and pop it back in tho, and also replaced the battery today so the EMU has definately been reset and no idiot lites have come on so I'd say it's safe to assume there are no CEL's on this OBD-I (idiot lights do light up when starting the car so they do work).

 

im having the same problem. with my idle but its 900-1300. i have aries forged pistons, valves, retainers, springs, aebs intake mani, hondata intake mani gasket, and a drag 3 kit. it started happening after i put the intake mani and the new turbo mani in.