Hi all I'm new here to the forum...I hope someone have the answer to this question....please help!! I have a 2000 gsr and did a B20z2 swap. now my problem is that I can't rev. over 4500 rpm, I'm running a stock 2000 P72 ECU. I'm hoping that the reason is v-tec. One of my friend told me its the distributor, my other friend told me I Might have a bad ecu... Can anyone please tell me why I can't rev pass 4500, Yes even when I drive punching on the gas, but once it hits 4500 rpm it starts to bog and won't go pass that all the way up to 5th gear well 5th gear I took it up to 5000 and thats it.

 

I would think ecu, because the ecu is meant to open the butterfly valves in stock gsr manifolds as well as activate vtec. You should change out that ecu for an ls ecu, and see what happens. If the problem persist, it could be an ignition coil going bad.

 

I tried to put a MSD box on. would not rev past 4000, so I took it off, aparantly there is an adapter for it, but I removed it. Do you ahave an aftermarket ignition. It is definetly electrical and nothing else in my professional opinion. Bad coil, rotor, cap, loose ign wire, could be any # of things. Oh yeah had a msd cap on it afterward, which ended up failing all together.

 

Hi ek-g6..thanks for the fast reply... Ok now I'm using the b20 intake manifold with my stock gsr throttle body. But I will try swapping out my stock ecu to ls, but the only different it should be is that of vtec. But I'll try that though, and hoping that its the problem. I'm swapping out the b20 and put back my stock gsr cause of smog and hope that the problems goes away. I was driving like that for a while with my car going only 4500 rpm lol for 1 1/2 yrs now. now smog is next month and need to swap everything back to stock.

 

No.. I don't have any msd or upgrade ign. wire. everything is stock b20.

 

If your just going to swap back the old motor, i would just hold off any repairs on the b20.

 

Is this butterfly valve on all B18C's, I never thought there was and I considered myself knowledgeable. The stock manifold is sitting in my garage, and i never saw those on it. I don't know

 

Yea true... I was just curious of why my car won't rev pass 4500 thats all, I wanted to find out what it was so that I know ahead of time before swaping back... you know lessons learn so we can share with others who need help if they ran into the same problems.

 

when I say ign wire I mean the wire that is controlled by ecu and runs through the interiors fusebox, which is coonected to a 15 amp fuse and the goes to the distributor. You would still rev past 4500 on spark plug wires that are crap, but that is how the motor would sound too.

 

If you have a haynes manual or better yet oem, electrical diagram comes in handy at this point.

 

Yes all b series and all honda's have butterfly valves and toyotas but I never seen throttle bodies on any newer hondas and acuras yet so I guess from the older models to 2001 should have butterfly valve. I've done motor swap for 5 yrs now putting pistons rings and motor together but when ran into electrical problem like this I would have no clue lol.

 

Lol I wouldn't know how to read them electrical pages I just go right pass it lol>

 

Okay, well you have a start anyway, hope you get it.

 

I doubt its my ignition wire. My car starts up fine revs fine, runs fine. Just when it hits 4500 thats it...it won't go pass that.

 

Okay, I KNOW my Skunk2 IM hasn't any. they probably were for emissions control or something huh?

 

Tacometer based on voltage accross its wire, knowing the rpm. Well I could try to explain, but all this runs to and from the ecu. Check it out like they suggested.

 

I have a skunk2 manifold too pro-series, I can't use it with the b20 caust it will not work. I am putting back on my stock gsr with the swap thought. Skunk2 IM should be fine with emission unless you don't have the C.A.R.B sticker.

 

The ecu is in limp mode because it is looking for those secondary butterflies which the b20 manifold doesnt have, thats why it wont rev past 4500 rpm.

 

If your b18c1 has a stock intake manifold, it will have those butterfly valves as known as IAB, it is internal, and it is wedged between the top and the bottom of the intake manifold. I believe that the jdm b18c did not come with them. Heres a picture to illustrate.

 

would you happen to know which wire it is. Like whats the color..if you know it from the top of your head its great but if you don't please post it for me later when you get the chance. I would appreciate that.

 

Working on EJ subes for the past year, the have they're tvg's, basically a butterfly valve. I'm starting to wonder if most every US spec foreign car has them.

 

Makes sense, I doesnt see increase in MAP(air) so it stops sending fuel and possibly spark.

 

You guys are confusing my. Are you guys talking about the butterfly flaps in the throttle body or some other butterfly something that I don't know about lol..Is there another butterfly

 

wow...I have never knew that we have a secondary butterfly. thanks mang

 

It is either blue or green, okay I just reviewed the manual. the blue is the tach output that runs directly to the ign control module, and the green/yellow is the ign input signal, also directly to ign control module. According to the diagram there is also an ign relay wired in parllel to the ign cotrol module's "IGN" and "Primary Output Control" (black/yellow). The ign contron module is part of the distributor indicated by the diagram and black/yellow is to fuse 9, but I doubt it is a fuse.

-Going to bed, 12:46 here in ohio-