94 surging idle insanely annoying

[94accord_carve]

I have a 94 accord ex, 2.2 F22B1 VTEC 5-speed manual transmission, with surging issues (surprised?). I've tried quite a few things but the car still starts and idles from 1,400 - 2,400 rpm's constantly when in neutral or car is under 2,500 rpm's.

First off I'd like to state what I've down thus far to try and alleviate the surging idle issue;

• Replaced IACV with known working IACV
• Cleaned FITV (working) & tightened plastic like bolt
• Swapped TB to a known working TB
• Checked IACV and TPS sensors - working as intended
• Checked virtually everywhere I can think of for vaccum leak
• Cleaned EGR ports (three were gunked up solid)
• Checked Spark plugs, plug wires, dist. - working as intended
• Replaced Gaskets to TB, Intake Manifold (Upper), and IACV.

I've also tried swapping the TPS and MAP sensor connectors, which will alleviate said issue until you hit the gas / car warms up then it surges again (also I know this is not good, but I had literally thought of everything!).

I do get two ECU codes, 14 and 41 - IACV and o2 Sensor heater (if I'm correct). I've tried everything to clear 14 up, even by replacing the entire unit itself with a known working IACV, CODE WILL NOT GO AWAY!

I've tested voltage as multiple people have wrote about, the voltages are correct for the IACV and the TPS, and MAP Sensors. I would like to note that if I cup my hand over the TB the car will stop surging a lot less (still surges, but barely). This is what leads me to believe there is a vacuum leak somewhere I have yet to find.

Please give me some sound advice as to what to check, and possibly how to check it. THANK YOU IN ADVANCE!

[93redcb7]

did you re-set ecu after changing the iacv? And yes, definataly a vacuum leak, car should die when the TB is covered, as there is no air going in. So, if you have checked all the gaskets, leads me to think that one of your hoses is leaking, pull each of your vaccum hoses off the intake manifold and cover the manifold with your finger or something, and this would tell you if one is leaking

[TAMPA]

I had the same problem as you, i went through and did everything you did and it still didnt fix it. It ended up being a vacuum leak in one of the hoses.

[ShowStopper71z2]

Tape off the throttle body so your hand are free. Get a can of starting fluid and spray around the intake manifold. When the motor revs up that is where your leak is coming from. If that does not work take one vacume line off at the time and block of the leak with your finger and if stops then you know u found the leak.

[TAMPA]

Tape off the throttle body so your hand are free. Get a can of starting fluid and spray around the intake manifold. When the motor revs up that is where your leak is coming from. If that does not work take one vacume line off at the time and block of the leak with your finger and if stops then you know u found the leak.

Thats exactly how I found mine, Ive been told you can use a propane torch and find them the same way.

[H311RA151N]

Thats exactly how I found mine, Ive been told you can use a propane torch and find them the same way.

IllinoisEric (IIRC) told me to use a propane torch to find vacuum leaks and it worked well for me.

[badfish82]

That is a fine idea indeed...i do that too find air leaks on 2 stroke engine intakes all the time mainly dirt bikes quads ect. Never really thought about using it for vacuum issues, learn me something new every day lol.