How's it going?
I put a B18C from a JDM ITR into my 1992 hatch. It is fast as hell, and pulls hard all the way to redline in 1st 2nd and most of the time in 3rd; the engine and transmission in no way feel worn or tired. The problem I am having is that when I am pulling hard in 4th gear, it stops accelerating at about 7200 RPM, and then hits the rev limiter at about 7800 rpm, but other times it will go up to 8500 with no problem and never hit a limiter.
Also, sometimes what I described will happen in 3rd gear, but sometimes it will let me take 3rd all the way to 8500.
Sometimes it will pull all the way in 3rd, but then when I shift to 4th the CEL comes on, and it drops out of VTEC, and the VTEC won't work even in the lower gears. The wierd thing is that when I shut the car off to check the CEL code, it won't throw a code, and when I restart the car, the CEL goes off, and the car starts working fine again, and the VTEC works again.

Does anyone know what this might be? The part that confuses me is that it is not consistant, and works fine in 1st and 2nd always, works fine for the most part in 3rd but sometimes doesn't, and in 4th and 5th the VTEC will cut out halfway through the revs.

 

check your oil level

 

Thanks for the advice, but I check the oil level everyday before I drive it (I know it may like overkill, but I love my car), and it is right where it should be. I also recently installed a new moroso oil pan which even slightly increased the oil capacity.
It is driving me nuts, because when it pulls, it pulls mad hard, but when VTEC cuts out at the top of 3rd and 4th, the car is nothing more than a glorified LS. And it always seems that it stops working at one of the few opportunties I get to disrespect V8's. I have all the VTEC I want when a bunch of Dodge Neon busters are around, but when that GT mustang or Z28 rolls up, I don't even want to try because the VTEC isn't working.

Please Help!

 

Find out what code it is throwing after you beat on it. It might be that your speedo isn't working or such things like that. Figure out what code is putting the car in "limp" mode (cel that makes the car have no vtec and run like crap.) Hope this helps. -Jason

 

That is the wierd thing. When the CEL came on, I pulled over to check the code. When I turned the car off and jumped the wire, it would not flash a code. Then as soon as I restarted the car the CEL was off, even though I didn't disconnect the battery to reset the ECU. Then when I drove it the VTEC worked fine again until I got on the highway and was pulling in 4th. Then the CEL came on again, and again the VTEC stopped working in all the gears. But as soon as I turn off and restart the car it resets, and I can never get a code to flash.

 

Sounds like the speed limiter to me...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by locash &raquo;</TD></TR><TR><TD CLASS="quote">Sounds like the speed limiter to me...</TD></TR></TABLE>

 

A CEL doesn't come on in 3rd gear. You have to get the light to turn on and check the code while the car is running. It could also be something like an o2 sensor or things like that. Let me know how it goes.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by sleepycivichb &raquo;</TD></TR><TR><TD CLASS="quote">It could also be something like an o2 sensor or things like that. </TD></TR></TABLE>

highly doubtful

 

Why don't you take a guess at what it is if you are so quick to criticize my help?

 

I already did.

now you wanna try explaining how a bad o2 sensor could cause this?

 

jdm type r engine don't come with vtec oil presure sensor, change the selenoid and run appropriate wires and your problem is solve. another way is chipping the ecu so that the ecu will eliminte the process of look for oil pressure

 

what ecu are you using? I agree with the speed limiter theory (found on JDM ecu's, and usually limits you to 115-120 mph).

 

Theres no way a speed limiter works just "somtimes", and theres no way hes doing 115 MPH in 3rd with a ITR Tranny.

 

it sounds as if your distributor is jacked, get a new one, trust me, or try a friends or something to test it out

or maybe just cllean the inside

 

Your coil could be bad, it could also be the ICM or TCM but it its most likely a coil problem.

 

wow 7200 at 4th gear? where the hell can you run that hard? i think its a speed limiter.

 

I had that problem one time.... i was using the P73 type r ECU and i was pulling hard all the way through 3rd gear, and about half way through 4th, the CEL came on and it still pulled, but not as hard. IE the CEL, turns the motor into 'limp mode', scared the **** outta me... so i baby'd it all the way to Rage Imports, talked to my boy Clint, and he said his homie with an R swap, had the same problem, it has something to do with the factory ECU, going past a certain speed, will cause it to throw a CEL

My ECU wasn't chipped, it was Factory.. so i swapped it out for a Hondata S200 and a P28, never had that problem since

 

Thanks for all the helpful suggestions everyone. I have been without the internet for a few days, so I haven't been able to respond.
First, I have a chipped OBD1 ECU programmed to very slightly more aggressive maps than a stock ITR P73. It is not the speed limiter, because a: I had it removed, and b: I've gotten it up to about 130 in 5th (without VTEC of course). I live in Texas, so there are plenty of long stretches of rode to rip on, and (knock on wood) there aren't that many cops per square mile to monitor **** away from the cities. I just replaced the O2 sensor so I don't think that that is it.
I will try to jumper the wire and get a code while I am driving, but it is difficult when you are the only one in the car. I might have to enlist a friends help.
I can try to borrow my brother in laws distributer to see if that is it.
I'm not sure what the ICM or TCM is.
I wired in a wire for the oil pressure switch from the ECU pin, and grounded it out to the body of the VTEC soelenoid (I read that this is the best way to do it when putting a JDM engine into a USDM car, and it is much cheaper than buying a soelenoid). I don't want to have to buy a soelenoid, so I will try that as a last resort, and hopefully, I can talk my brother in law into letting me try his out first.

Thanks for all the help, any more suggestions are always welcomed. I will keep you informed on what works, so all of you that are making bets will know who the winner is

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by BigBoulda &raquo;</TD></TR><TR><TD CLASS="quote">I wired in a wire for the oil pressure switch from the ECU pin, and grounded it out to the body of the VTEC soelenoid (I read that this is the best way to do it when putting a JDM engine into a USDM car, and it is much cheaper than buying a soelenoid).</TD></TR></TABLE>

maybe I'm missing something here, but you need a vtec solenoid whether its JDM or USDM. You say you have a solenoid, so what do you mean by "much cheaper than buying a solenoid"? Is your ecu a chipped p28? If its not a p28, run the vtec pressure switch ground to a26 (can be grounded to head on p28).

 

[QUOTE=IHateJDM]

maybe I'm missing something here, but you need a vtec solenoid whether its JDM or USDM. You say you have a solenoid, so what do you mean by "much cheaper than buying a solenoid"?

I was referring to a suggestion made by someone earlier that I switch over to a solenoid from a USDM car that has an oil pressure switch (whereas the JDM solenoid does not have an oil pressure switch). I was just saying that it is cheaper to ground that wire than buy a new solenoid for several hundred dollars.
I had my stock P06 ECU chipped and converted to VTEC. I'll have to check to see where I pinned that wire out to, but I don't think the VTEC would work at all if it was pinned in the wrong slot, but maybe so.

 

I don't see how VTEC can work just fine in the first three gears and just *** out in 4th and 5th. I really don't think its a VTEC issue.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dreamer &raquo;</TD></TR><TR><TD CLASS="quote">I don't see how VTEC can work just fine in the first three gears and just *** out in 4th and 5th. I really don't think its a VTEC issue.</TD></TR></TABLE>

What I don't get is why it only happens in the higher gears. It is definately the VTEC dropping out, because there is a distinct change in the tone of the exhaust when the VTEC is engaged. Also, it will continue to let me rev past that point (although it does cut me off early at 7800), but without the VTEC lobe in effect, the car has no power that high in the RPM range, so it is useless to keep revving it.
All the stuff that I thought it might be, would affect it all the time regardless of the gear.
I tried to jump the CEL wire while the car was running, but it did not flash a code; the CEL just stayed on. And then when I turn the car off to go through the correct code reading procedure, the CEL resets itself.
This is boggling my mind.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by BigBoulda &raquo;</TD></TR><TR><TD CLASS="quote">What I don't get is why it only happens in the higher gears. It is definately the VTEC dropping out, because there is a distinct change in the tone of the exhaust when the VTEC is engaged. Also, it will continue to let me rev past that point (although it does cut me off early at 7800), but without the VTEC lobe in effect, the car has no power that high in the RPM range, so it is useless to keep revving it.
All the stuff that I thought it might be, would affect it all the time regardless of the gear.
I tried to jump the CEL wire while the car was running, but it did not flash a code; the CEL just stayed on. And then when I turn the car off to go through the correct code reading procedure, the CEL resets itself.
This is boggling my mind.</TD></TR></TABLE>

thats just bizarre. try borrowing an ECU that you know works from somebody and see if it solves your problem.

 

LOL, my car does the same ****. Actually its not funny and I'm still trying to figure it out myself. I think its my dizzy but I haven't found one to swap it out with. Mines is on a obd0 b16 though if you figure it out let me know. Check out your distrubutor I still think thats the coulpret.