problems with new tune..
problems with new tune.. ok here's the history:
1st setup:
hotcam, shorty headers, catback, stock cat, stock tb
- got it tuned by pcmforless, ran great!
2nd upgrade:
still hotcam, 1.6rr, longtubes, no cats, true duals, 52mm tb
- ran the old tune(above), runs strong but pops/backfires when WOT. Drives normal except WOT.
Just got my new tune for the new mods and i can't even drive the car down the road.. It's been double checked by pcmforless, and emailed to me twice. i've loaded it 3 times with no driveable success. it dies, shutters, shakes and has no power.
I'm running the old tune right now to be able to drive the car. PCMforless said i have something mechanically wrong?
Here is a vid with the new tune: http://lt1engine.com/problem.mpg
I've replaced virtually every singe sensor with about 3-4 months run time on them. (02's,knock,water temp,pcv,new plugs,wires,opti). I am running the original tps, maf, iac, iat, map and evap.
btw i'm not throwing any engine service codes.
1st setup:
hotcam, shorty headers, catback, stock cat, stock tb
- got it tuned by pcmforless, ran great!
2nd upgrade:
still hotcam, 1.6rr, longtubes, no cats, true duals, 52mm tb
- ran the old tune(above), runs strong but pops/backfires when WOT. Drives normal except WOT.
Just got my new tune for the new mods and i can't even drive the car down the road.. It's been double checked by pcmforless, and emailed to me twice. i've loaded it 3 times with no driveable success. it dies, shutters, shakes and has no power.
I'm running the old tune right now to be able to drive the car. PCMforless said i have something mechanically wrong?
Here is a vid with the new tune: http://lt1engine.com/problem.mpg
I've replaced virtually every singe sensor with about 3-4 months run time on them. (02's,knock,water temp,pcv,new plugs,wires,opti). I am running the original tps, maf, iac, iat, map and evap.
btw i'm not throwing any engine service codes.
i can hookup a laptop with pcmcomm.exe http://carputing.tripod.com/9495LT1Edit.htm . but i dont have any type of scan tool other than that.
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Verdad Gallardo well i emailed him and he sent me an email back saying he checked it and i have some type of mechanical problem. i sent an email back saying i'm driving the car perfectly fine except for wot popping with the old tune. I haven't recieved a response.
I'm 100% sure the old tune works, because it's my daily driver and thats the tune in the car right now. I got him to email it twice, just in case he sent the wrong one, and i got the same results.
I'm 100% sure the old tune works, because it's my daily driver and thats the tune in the car right now. I got him to email it twice, just in case he sent the wrong one, and i got the same results.
Last edited by luckyou03; May 5, 2006 at 03:14 PM.
Originally Posted by blkchevyz
what valve springs are you running?
TECH Fanatic
Joined: Oct 2003
Posts: 1,101
Likes: 0
Originally Posted by luckyou03
lt4 springs with 1.6rr on lt4 hotcam, car starts to go on new tune, but then falls on it's face and dies, shakes.
i'll look at the tune when i get home
dont know if this matters but have you replaced your opti, or how many miles do you have on it? i had the same problem when i did the 230/236 cam and it ran fine with the tuning till it started to miss and pop when i got on it. replaced just about every ignition related component then found out my opti was shot? mine would run fine under light loads but when i would go WOT it would miss and pop but it would still keep pulling till i let off. finally after a few days it just started missing at all rpm's. dont really know if it helps but its worth a try.
update! took the pc out in the garage ran the pcmcomm.exe scan tool. here are the results:
car off
Start up
car running 1 (open loop)
car running 2 (open loop)
car running 3 (open loop)
car running 4 (closed loop)
car off
as the car warmed up the right 02 stayed consistantly lower.
car off
Start up
car running 1 (open loop)
car running 2 (open loop)
car running 3 (open loop)
car running 4 (closed loop)
car off
as the car warmed up the right 02 stayed consistantly lower.
Almost sounds like you are hitting an incorrectly set rev limiter... The rev limiter should be set for something like 200-300 over the point your cam really runs out of steam, which on the hot cam would be a setting like around 6300-6400.
Does it die as soon as you open the throttle all the way or do the revs have to climb to a certain point then it dies? That can be a hard point to find in a low gear - try 3rd at a moderately low speed and see if it is TPS dependent or RPM dependent.
Jim
Does it die as soon as you open the throttle all the way or do the revs have to climb to a certain point then it dies? That can be a hard point to find in a low gear - try 3rd at a moderately low speed and see if it is TPS dependent or RPM dependent.
Jim