Acting like a vacuum leak.

B16, B18, B20
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Acting like a vacuum leak.

By That One Dude
- Thu Feb 02, 2012 11:13 pm #293088 I've been gone for a while, but I'm back with a Frost White 1998 GSR. I have recently (two weeks, 300ish miles) rebuilt the engine with the following:

81.25mm ITR pistons
ACL bearings
Skunk2 IM
Skunk2 Alpha Series header
Skunk2 Alpha Series 66mm TB
Injen CAI
Buddy Club 2 layer head gasket
Mizu radiator hoses
P28 ECU chipped with Crome on a B18C1 with Skunk2 IM base map
All of the seals and gaskets are new from the dealer except for the head gasket.
Compression ratio calculates out to 11.39:1, static.

Problem is as stated in the title. I have a fluctuating idle that is acting like a vacuum leak. When I come to a stop light, I throw it in neutral with my foot off the clutch. It will fluctuate from 1100-1300rpm. I have bled the cooling system twice, but found another small pinhole leak and will be fixing that and bleeding the system again in a few minutes. I replaced the stock throttle body with a Skunk2 Alpha series 66mm TB thinking that the B16 TB I had bought had a leak at the throttle plate shaft. MAP sensor, IAT sensor, IACV, and TPS all have new gaskets and o-rings as required. I Hondabonded (new verb, use it and spread it) the MAP sensor, IAT sensor, and the TPS to insure that those were not leaking.

I have a CEL for the IAT sensor. I'm thinking that I might have either extended the wrong wires or my solder joints are shit. That's a different problem, I imagine.

I know that the P28 looks for a FITV that I do not have, nor do I have an electrical connector for it on my wiring harness. Not sure if that is causing the fluctuation, just throwing that out.

Any ideas?
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By Eg6H2D
- Fri Feb 03, 2012 12:34 am #293095 Did you pull out the IAT and see if it's still good? Sometimes they melt in there some how. happened to a buddy of wines with a JDM b16..


Yea the P28 does look for the FITV. as it will adjust the IACV to compensate. I have that problem on my Single cam when i put on my Skunk2 manifold and new 68mm TB.. it would do it. very annoying. the way i fixed it. Hondata S300 to control the IACV. and keep it where it's supposed to be. =]

Hondadata does wondered.

What you can do is order a new chip. and see if they can adjust the IACV for you.

Or invest in Hondata s300

:thumb:
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By That One Dude
- Fri Feb 03, 2012 1:07 am #293098 Yeah, I looked at the sensor itself when I was swapping the stuff over from the stock GSR IM. It looked fine. Going to check the voltage and the wire colors tomorrow.
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By That One Dude
- Fri Feb 03, 2012 1:41 am #293105 I never left the game, amigo! My soul belongs to the Integra! This one is the cleanest of the bunch with an exceptionally clean interior and fantastic paint. Now if only I could get my engine to cooperate so I can get her tuned...
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By JUICE
- Fri Feb 03, 2012 1:45 am #293108 soo.. sounds like we're long overdue for a "other rides" thread with lots of pics.. :lol:

didn't you get deployed or something like that??
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By That One Dude
- Fri Feb 03, 2012 3:25 am #293132 I don't have any pictures of the new ride. This is actually the first thread I've posted regarding anything on it. Considering the past luck with my ITR, I won't be posting any pictures of my Betsy.

Got my CEL fixed. Turned out to be the wrong connector attached to the IAT sensor.

By bigpunn421
- Fri Feb 03, 2012 3:59 am #293135 i have same problem with my car. i swaped the throttle body with a 70mm omni one without the FITV. my car will not idle warm. and when i start it cold i have to give it gas. but it will still bounce up and down.

i checked ECT, TPS, MAP, IAT, IAC, vac lines, gaskets, fuel, spark...everything. so i think the fitv is reason

once the car warms up the idle gets worse sometimes even stalls out the rpm drops so low.

i called my tuner and he said its because of the new tb. you can adjust the iac % in the tune to compensate for no fitv. but you can skip getting it retuned by instaling the old throttle body.

your oem throttle body isnt restricting your motor at all. so you will not notice any power increase. youll gain throttle response but i would rather have a car that idles over thottle response.

the iftv controls how much air your iac lets into the motor at different temps. without one your ecu doesnt know what to do unless you tune it

By bigpunn421
- Fri Feb 03, 2012 4:03 am #293137
EG6b20R wrote:Did you pull out the IAT and see if it's still good? Sometimes they melt in there some how. happened to a buddy of wines with a JDM b16..

:thumb:


how many volts should be going to the IAT?

and how many ohms should the iat have?
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By That One Dude
- Fri Feb 03, 2012 12:11 pm #293186 Voltage to the IAT is supposed to be battery/alternator voltage. Resistance between 0.4-4.0 ohms.

Like I said last night, CEL is gone. Still idles like it's got a vacuum leak from time to time at a stop light.

Going to douse the thing with carb cleaner tonight to see if there really is a vacuum leak or not. Fixed the pinhole coolant leak and bled the system yesterday afternoon.

By bks84
- Fri Feb 03, 2012 9:41 pm #293223
EG6b20R wrote:Did you pull out the IAT and see if it's still good? Sometimes they melt in there some how. happened to a buddy of wines with a JDM b16..


Yea the P28 does look for the FITV. as it will adjust the IACV to compensate. I have that problem on my Single cam when i put on my Skunk2 manifold and new 68mm TB.. it would do it. very annoying. the way i fixed it. Hondata S300 to control the IACV. and keep it where it's supposed to be. =]

Hondadata does wondered.

What you can do is order a new chip. and see if they can adjust the IACV for you.

Or invest in Hondata s300

:thumb:


How exactly does a P28 look for a FITV?

Stock cams, no?

Id spray the injector o-rings (@ the base of injector where it goes into the manifold) w/brake clean and see if the idle changes. If theres a leak, then the idle should increase, if not it should stay the same.
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By That One Dude
- Fri Feb 03, 2012 10:20 pm #293230 I suppose looking was the wrong verbage.

Yes stock GSR cams for now. I would have expected something similar to this with super high lift and duration cams.

I plan on spraying down the whole intake and fuel systems when I get home. However, it has not acted up since I connected the proper connector to the IAT sensor. Ergo, I believe that my problem is solved.
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By Eg6H2D
- Fri Feb 03, 2012 11:06 pm #293232
bks84 wrote:
EG6b20R wrote:Did you pull out the IAT and see if it's still good? Sometimes they melt in there some how. happened to a buddy of wines with a JDM b16..


Yea the P28 does look for the FITV. as it will adjust the IACV to compensate. I have that problem on my Single cam when i put on my Skunk2 manifold and new 68mm TB.. it would do it. very annoying. the way i fixed it. Hondata S300 to control the IACV. and keep it where it's supposed to be. =]

Hondadata does wondered.

What you can do is order a new chip. and see if they can adjust the IACV for you.

Or invest in Hondata s300

:thumb:


How exactly does a P28 look for a FITV?

Stock cams, no?






Id spray the injector o-rings (@ the base of injector where it goes into the manifold) w/brake clean and see if the idle changes. If theres a leak, then the idle should increase, if not it should stay the same.


Lol. it doesnt look for it electronically sorry. But the 2 holes in the Stock TB. one for IACV and the other is for the FITV.. the FICV needs to be working correctly as far as opening or closing if not it will throw the IACV off and have a Higher then normal Idle. IDK when i got my HONDATA in there problem solved. I plugged that hole and the HONDATA keeps the idle stable now through the IACV...
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By Eg6H2D
- Fri Feb 03, 2012 11:10 pm #293233
That One Dude wrote:I suppose looking was the wrong verbage.

Yes stock GSR cams for now. I would have expected something similar to this with super high lift and duration cams.

I plan on spraying down the whole intake and fuel systems when I get home. However, it has not acted up since I connected the proper connector to the IAT sensor. Ergo, I believe that my problem is solved.


Yea "looking" what the wrong wording... :thumb:

By bks84
- Fri Feb 03, 2012 11:23 pm #293236 ok, i was wtf. i knew it didnt look for any type of electronic input.

i just ran an obd2 gsr throttle body (which doesnt have a FITV like a b16) and had no issues. didnt require hondata or anything.
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