F20b swap revs to redline by itself.

[GhostAccord]

The stock Honda ECUs have a vacuum leak fuel cut... it's activated when the manifold air pressure rises and the TPS % doesn't change, or is below a certain %. That's why most people get that idle surge when the IACV is bad or they have a vacuum leak. If the ECU didn't have this cut the engine would rev as high as it could with the amount of air leaking in.

Do you have another ECU that you can try? It would be helpful if you have a chipped ECU that you could monitor the Sensor signals.

[evil_demon_01]

The stock Honda ECUs have a vacuum leak fuel cut... it's activated when the manifold air pressure rises and the TPS % doesn't change, or is below a certain %. That's why most people get that idle surge when the IACV is bad or they have a vacuum leak. If the ECU didn't have this cut the engine would rev as high as it could with the amount of air leaking in.

Does that apply to all Honda ecu's?
Because a 96-98 CRV will rev sky high if you leave the intake resonator off.

The only way that the engine can rev up is if enough air is getting in.
If the throttle plate is closed, then it cannot rev up.


OP - Are you sure the brake booster is connected? And that the gaskets are OK? - Specifically the intake to head gasket.

[GhostAccord]

I have never seen that before. The ECU's that I have worked around have had it. That's why they surge if you unplug a vacuum hose. I have never seen an engine surge just because you remove the intake resonator, unless it has a vacuum hose that you opened to the air. Then again I have never worked on a CRV. I'll have to try it on my buddies this weekend and see what I can find out by hooking it up to the scanner.

And the engine can rev up with the throttle plate closed, the air could be coming in from any number of other possible openings. An unplugged hose, any of the gaskets leaking, from the throttle body down to the injector o rings. If the EGR plate isn't sealed or the IACV gaskets toast causing a leak....there are numerous places for air to get into the intake other than the throttle plate.

[evil_demon_01]

I have never seen that before. The ECU's that I have worked around have had it. That's why they surge if you unplug a vacuum hose. I have never seen an engine surge just because you remove the intake resonator, unless it has a vacuum hose that you opened to the air. Then again I have never worked on a CRV. I'll have to try it on my buddies this weekend and see what I can find out by hooking it up to the scanner.

And the engine can rev up with the throttle plate closed, the air could be coming in from any number of other possible openings. An unplugged hose, any of the gaskets leaking, from the throttle body down to the injector o rings. If the EGR plate isn't sealed or the IACV gaskets toast causing a leak....there are numerous places for air to get into the intake other than the throttle plate.

CRV intake resonator is part of the intake manifold (it sits on top of it)


That was my point - If the throttle is closed then there HAS to be a leak somewhere else.
Hence why I said check the booster hose and intake gasket.

[TracieS]

Ok thanks for the info guys. Ill go over all the intake bolts again today and make sure there tight. Ill let yall know what I find out.

[TracieS]

Dont use a p13 with the f20b. it will run like crap! That might be your issue right there. Just wait till you get the chipped ecu from drummersteve.

Yea I probably wont get one till next week I am just trying to get everything worked out right now. Thats the only reason I am using the p13.

[TracieS]

I went back over everything checked everything and still the same thing so I am starting to think it is a Ecu problem working on getting a chipped one asap.

http://www.youtube.com/watch?v=iaQOF...ature=youtu.be

[evil_demon_01]

Is the check light on in that clip?
And I thought it revved right to redline?

[TracieS]

Its for the Air intake temp sensor I forgot it was unplugged. But it didnt change nothing. Im not for sure how far it goes I just cut it off there because it doesn't settle out it feels like its going to keep climbing and I dont want to damage the engine before I even get to drive it.

[dj_ender]

Its for the Air intake temp sensor I forgot it was unplugged. But it didnt change nothing. Im not for sure how far it goes I just cut it off there because it doesn't settle out it feels like its going to keep climbing and I dont want to damage the engine before I even get to drive it.

And you can't hear any air sucking in thru a leak in the bay? I wonder, start it, pull the IACV. Does it die? If so most likely it's a vacuum leak somewhere.

[TracieS]

Tried that to and nothing I just honestly think its the ecu now. All vacum lines are capped off with brand new caps and the intake has fresh gaskets. All the bolts are tight.

[dj_ender]

Tried that to and nothing I just honestly think its the ecu now. All vacum lines are capped off with brand new caps and the intake has fresh gaskets. All the bolts are tight.

Damn man, sounds like you should just wait for that ECU. I know it sucks, but just a little longer, right?

[TracieS]

Damn man, sounds like you should just wait for that ECU. I know it sucks, but just a little longer, right?

Drummersteve is in Greece or something right now at-least thats what I got from his facebook. But I am talking to a local guy right now see if we can get something going.

[dj_ender]

Drummersteve is in Greece or something right now at-least thats what I got from his facebook. But I am talking to a local guy right now see if we can get something going.

Shitty. But you gotta do what ya gotta do. It would drive me nuts having my car sitting there, waiting. I wouldn't wait either, I'm impatient.

[evil_demon_01]

Tried that to and nothing I just honestly think its the ecu now. All vacum lines are capped off with brand new caps and the intake has fresh gaskets. All the bolts are tight.

You positive you scrapped all the old gasket off first?
I've seen before where just a little peice was left and the manifold won't sit flat, therefore wont seal.


Try this - Block the intake and try start it, If it still starts then air is definately leaking in some where else.