KillinEm18

I am trying to figure out what this is. Its on the intake manifold. If i hook a vaccum line to it or block it with my finger, then the engine starts to make a loud vaccum leak sound but unplugged the noise goes away, also the engine idles bounces but bounces less with it unplugged. any help would be great, thanks. :confused: :confused:

Also the car does this thing where it acts like it doesn't want to go when you drive, like a real hesitation or stutter then will all of a sudden kick in, any incite on this would be helpful also....



Here is a video of the problem I have with Idle on cold starts...
http://youtu.be/h3flGQiR8dg

Chilloutdamn

Thats weird mine didnt have that thing. Did you run your shift linkage yet by any chance? Im running into some frustrating problems not being able to shift correctly...

KillinEm18

i actually got the car with the swap already, i just got my p28 back from being chipped and its still doing the bouncy idle, but im more concerned with the hard hesitation it has cause its almost like it just doesn't want to go at all...

KillinEm18

Also when starting the car cold, it acts as if it goin to die from a low idle or like 150RPM but it doesnt cut back off, once it is warmed up the idle doesnt go that low. any idea what this could be? maybe the Air Boost Valve (highlighted). but it does it weather or not its hooked up.

Chilloutdamn

Sounds like your idle air control valve. On the front of the intake manifold, right in front of the injectors. Try taking it off and cleaning it out with brake cleaner. That usually does the trick.

KillinEm18

the IAC wouldnt cause it to hesitate hard and not want to go when i try to pull off from a stop sign tho would it?

Chilloutdamn

No the IACV would just cause the idle to surge up and down when the engne is cold. Have you checked your check engine codes yet?

KillinEm18

yeah, only codes r o2 and vtec(cause its not wired right now)

KillinEm18

ive figured out the whole surging idle thing, now im trying to figure out why it acts like it does not want to do anywhere. idk if it the fuel pump maybe going out or something not wired right, or a fuel pressure regulator. it just has me stumped right now. and nobody around here has much experience with h22 in an eg. and i dont have money to take it to a shop.

jcdimvic

as for the picture above, just leave the vacuum unhooked, it acutally goes into the air intake tube... will not have any effect on the performance wise. when you buy an aem intake they actually give you a little foam filter that goes onto it. as fas as the hesitation goes it may be caused from the O2, also pull of your dizzy cap and make sure your rotaor and cap are in good condition. i have done countless h swaps in eg's i had this on one of them and i think it was the O2 but this was years ago and my memory is not what it used to be.

KillinEm18

Ok so getting a tune to delete the O2 could solve the problem? cause i have dc sport headers and there is no spot for an O2, and if i delete the O2 through a tune how will the computer adjust the A/F Mix? Thanks for the incite though.

typemismatch

The o2 helps in closed loop, during normal operation.

As the car is running it is looking up fuel and timing in the tables in the computer, it uses values from the TPS, O2, IAT, etc. to interpolate the values from the tables. The tables are hard values that the computer starts with for fuel and ignition timing. Then it uses the sensor values to adjust to what the car needs as it is running.

When you tune the o2 sensor out, the car is in what is known as open loop, where its not using any adjustment to the fuel and ignition tables. Its just running off the raw values in the tables.

This is good during tuning, and for full race builds, but can be damaging to a DD motor that sees all sorts of different weather conditions. Since the ECU isn't doing any adjustment to the fuel and ignition tables, when the air temperature rises or falls, you can run lean or rich. Lean conditions can kill pistons, rich conditions can kill rings and bearings depending on how rich.

KillinEm18

yeah, but i have no spot for a o2 and i need my car to run right. im just trying to figure out the best option

snobordboy

If you don't have the cash to do a full tune on the car, spend a few bucks to buy an O2 bung and have it welded into the exhaust, the bung is like 5 bucks, and welding, well that depends on your area.

KillinEm18

Well Ill have the money to get a full tune soon, but i want it fixed now n i dnt have the money to buy an O2 now

SCRUBBAGE2

this might sound crazy, but i also had the stutter and then ***** to the walls issue. Mash the gas and it boggs, then all the sudden warp speed. Although sometimes i would get a popback before launch. A mechanic told me to put a few gallons of 103 or any other high octane fuel (not too high) and top the rest of the way off with premium gas. I had the isse maybe twice after on that tank, and never had that problem ever again. This was on my f22 before i swapped the h in. Might worth a shot.

KillinEm18

Well I run 93 in it and its not doing it all the time, but im thinking my IACV is not working.

KillinEm18

I just added a video of how bad the idle is at cold start...