Throttlebody/Idle problem

[carotman]

Hi guys!

I installed my JG INtake manifold this week-end. I must say this really helps the engine to breathe like it should. I got awesome power up to 7200 rpm now and it just loses traction when shifting into 2nd gear (not just a chirp). However, I have some problems with the idle.

I installed an Integra Throttlebody to match the JG intake. The TB seems to be fine but no matter what I do with the idle adjust screw, it just won't idle high enough and the engine stops. If I press a little on the gas, it's all ok (like half a milimeter). This winter, I completely took apart the Throttlebody and I think I might have reinstalled the throttle plate wrong. The car just seems to be missing a little bit of air at idle. If I unplug a vacuum line, the car will idle at 1100 rpm without a flaw.
I don't seem to have any kind of vacuum leaks since the car idles too low (it would be a little too high with a leak). The car is supposed to idle even if the EACV is unplugged so it shouldn't matter.

The car seems to be getting enough gas since the Fuel pressure gauge shows around 35 PSI at idle.

I think I just messed up the Throttlebody,... does anyone know a simple way to adjust the throttle plate? (or has an idea of what could be the problem)

[mouchyn]

yeah, there should be a little stop screw right near the butterfly wheel (where the cable attaches). spin that screw in a tad more to adjust the throttle plate stop point.

Hopefully, the slight adjustment you need to make won't throw off the TPS reading too much. If you do get some ghostly performance or throttle response problems after adjusting that stop screw, you're going to have to adjust the TPS by itself.

[smufguy]

technically the way idle stop screws work is that they act as a valve in the passage that connectes before and after the throttle body and the idle stop screw acts as an adjustable valve. Try pulling out the valve completely and see if it still has the nylon case around it in tact, if its fugged up and lodged inside the teeny hole then it could be the proble. IAC should be working regardless of the engine rpm i guess.

if the car wont hold the idle, then its the only way i can think its possible. Besides, you are technically well intelligent and me saying anything else is not gonna make sense cause u probably checked those out. The only think i can think of is that check out the TB gasket and see if it was installed upside down. Something is blocking the passage where the idle stop screw sits in.

[mouchyn]

remember the idle set screw (in the TB housing itself) and the butterfly plate stop screw are two different things. Both should be checked.

and smufguy said, the idle set screw assembly could just be all gummed up. If turning it doesn't change the idle at all, then something is wrong. Once you get that cleaned out and working properly, the next thing to check would be the throttle plate stop screw.

[carotman]

I removed the screw and sprayed TB cleaner inside the hole and the car died instantly. I removed the TB and saw nothing that blocked the idle adjust screw. The little O-Ring and gasket residue were still in there too.

When comming to a stop, the idle is around 1000 rpm and will remain there for like 5 to 10 seconds until it drops again (too low). I guess this means the IACV is working.

I will also check the PCV hose since I had to lenghten that hose and it may have a kink somewhere (i forgot to check that one).

Since I played with the Throttle plate, I'm sure it's part of the problem but you never know :(

The TB I got is a USDM unit and doesn'T have the removable screws... I hope it doesn't throw the adjustment off or I'll have alot of fun removing those hehe.

[AccordEpicenter]

you have no more eacv, just fast idle valve? Correct? IF thats true, id just pull a vac line off to pick up some rpms

[carotman]

I have a fast idle valve and an IACV valve.

[mouchyn]

The TB I got is a USDM unit and doesn'T have the removable screws... I hope it doesn't throw the adjustment off or I'll have alot of fun removing those hehe.

i assume you're talking about the TPS? just use a file or a dremmel and cut a notch in the rivets. then a normal flat head screw driver will back the bolts out. Normal bolts and be put back in their place.

have you tried adjusting the throttle plate stop screw? (not the idle control screw)

[carotman]

I have already adjusted the TPS on many cars but never messed with the throttle stop screw. That's the next thing I will do since the thing just seems to lack a bit of air. I hope the IACV and FAst idle valve are in working condition (they seemed to)

[RobT5580]

I thought the FITV are only used in cold start? I have the edelbrock 65mm Type R TB so i dont even use the FITV which from what i read just lets air in for cold starts. Otherwise w/o one you have to hold the throttle open for warm up.