pvt_awol

I don't want to type a book, but I need help.

I will make a long story short. LS/VTEC build, with turbo. Rods/pistons/sleeves/etc.

tuned on Hondata S-300. Made 400+ whp, tuned it for 350whp, to daily drive on 10 psi.


Ok, car ran fine. Got into a crash (rolled car a few times) and then swapped everything into a new chasis. Engine fired right up, everything works just like it did. No leaks, etc. Tested the car for a week, before I decided to "get on it".

I uploaded my old s300 map, and the S manager software updated my firmware on the ECU. Now, when I get on it, the car pulls hard until VTEC (5500 rpm) and then it hits like a rev limiter. I've looked over the map, everything is accurate. VTEC set right, everything.

Here is the thing, when I enable secondary tables in the hondata, the VTEC works fine. Pulls VERY hard up to 8000 rpms. BUT---- it wasn't tuned with the secondary tables. It has NEVER had them enabled. My tuner says that it's a mechanical problem. Any help? If I partial throttle it (without engaging VTEC) the car revs up to the actual 8000 rpm limit.

HELP!!!!!

pvt_awol

damn. everyone answering "VTEC sticker" questions, and what brakes for what car, and yada yada.

No one has any clue to help me out though? C'mon.......

93egSLEEPER

i would try putting a stock ecu like a p28 or p30 in it and seeing if it has the vtec engagement issue to eliminate the hondata error. if it is mechanical could be something in your head causing the cams to not move correctly

rick_rabies

the current setup is it the same as the old one?
is your mapsensor ok? it seems to be a safe catch
like the butterflyes in a gsr mani. if you have a gsr map (i had this problem and figured it out) instead of the secondary gsr butterflies opengin its now a rev limitr.
i didnt have the stock gsr manifold on but the computer thought so.

pvt_awol

^

thanks for the tips guys. I'll check the map sensor. As for it being the same, it is EXACTLY the same. I pulled everything from the wrecked car (including harness still on the engine) and dropped it into the new car. Made the harness connections at the shock tower, and viola.


And as for using a stock ECU, I can't do that. The engine is a built LS/VTEC with turbo. The injectors are 780cc units. A stock ECU would blow it up.

The weird thing is, the S300 seems to be doing what it does. Boost is what it should be, all readings are the same as they always have been. But when I get to VTEC, it just cuts out. Like a rev limiter.

pvt_awol

oh, and I'm using a GM 3 bar map sensor.

rick_rabies

stock ecu wont start the car would it?
mine wont.
try the tuning/ engine management thread

pvt_awol

^

I don't see why a stock ecu wouldn't start it. I would NEVER drive with it like that, but I'm pretty sure it could start it. The injector pulse, and duration would be all f'd up though, it'd probably run like crap. LOL.

What I may do, throw a stock p30 map on the s300, and change the injector size. (the program will adjust for the bigger injectors) and then see what happens. Of course, running the car up to VTEC, if it ends up running lean, could be the end of all of it.

93egSLEEPER

I wasnt saying to just throw a virgin ecu on it and run it. what i failed to explain in my thoughts was get a ecu, chip it with like crome pro or neptune, do a street tune on it and get the basemap set and see how the vtec responds from there.

pvt_awol

^

yeah, but for the money to do that, I could have my tuner just retune it. Of course, he will fix what's wrong, or figure it out, and I'll pay for it in the end either way.

I was trying to fix everything I could think of, to get it to work, before just having it completely re-tuned.

Loganaor

I sorta had the same problem with another car of mine, ended up being a bad cam sensor... just a thought might help might not... gl and let us know what it ends up being.

ej1239

same exact thing happened to my friends car and it was the knock sensor but if your car is chipped it shouldnt matter but idk wont hurt to look my friends car hit the rev limiter thing to at 5500

pvt_awol

oh man.

Ok, after messing with things all weekend, I've discovere that VTEC is in fact engaging. The ECU is sending the proper signal, the solenoid is opening, and VTEC is "cracking". However, as soon as that happens, it rev limits.

I'm gonna replace the dizzy with a known good one. Try that out. Something has me thinking that it screwed up.


Still.... that doesn't make any sense why it would work if I enable secondary tables on the S300. Oh well. I'm gonna try it anyways. Couldn't hurt. I'll report back, thanks for the input guys.

pvt_awol

anyone else feel like chiming in? Since now we know that it isn't a VTEC issue. Anything anyone want to add?

rick_rabies

it seems to be in the ecu management. like you said it will cost $ but if your tuner duder can do at least one pull. i bet he can find it somewhere in the tool bar and click something and then finished

Jrodbuilt

I know it's been very long lol just wondering what ended up being your problem? I have the exact problem with my turbo b16 eg