Need help diagnosing odd problem with LS1
10-08-2004, 08:55 PM
#1
Need help diagnosing odd problem with LS1 2000 Camaro, lots of mods….drivability issue and performance issue-
Car was running fine, changed plugs, changed oil and filter, tranny fluid and filter, cleaned nitrous filter, new fuel filter, did front brake pads, polished out headlights…
Drove fine, had nitrous in the line (didn’t race anyone that night), shut the bottle and hit the button (ran hard for a second, then flooded with fuel), check-engine light came on, drove it for a few minutes to clear everything out, light went out, felt fine. Next day, too friend for a ride, ran weird, idled high, very unresponsive, rpm’s came up real slow (like an ultra tight converter or something)…tried it on and of the bottle, same response until above 5,000 rpm, then the rpm’s came up faster. When driving, car would accelerate on its own all the way to 45 mph or so and stay there (from a dead stop with no gas being applied), when shifting into neutral at 45 mph, the rpm’s would climb to 1500 or so, and then slowly fall. If you hit it on a 40-50 roll, it would accelerate slowly until 5-5500 rpm then it would pick up speed.
Here is what I have done (unsuccessfully) to address this problem:
Disconnected/reconnected battery after every change-
Replaced IAC with another IAC from a good running, same year Camaro
Cleaned IAC
Replaced TPS
Checked for intake leaks with carb cleaner (none found, no surging at all)
Autotap- no codes
Snap on scanner- no codes
Had friend rev engine to 1800 rpm or so, disconnected IAC (per mechanic friend), car was more drivable down low, did not want to idle high or go to 45 mph on its own, but still felt sluggish (again like a ultra tight converter)
Went to Livernois to have car re-tuned…used a brand new ECM, did the tuning, made good power (dyno pulls were at 70 mph and above) made 580 rwhp and 644 tque so engine is not damaged, and everything ran great on the dyno-
Test drove it and the exact same problem as before with drivability. Tried replacing Metco breather with standard oil cap, seemed to help lower the idle a little but no major difference. Put foot on brake and foot on gas…floored gas…rpm’s went to 1800 at WOT on the brake, did not go above 1800 rpm’s or spin tires. At this point I thought the converter was bad, drove back home and shipped it to P.I. for a check. Everything checked out fine, they are restalling and sending back to me this coming week.
Having mechanic check intake gaskets for possible leaks, do a compression test, and putting 3.42 gears in rear end, and sending computer back to Livernois for gear swap. I believe the computer is now set to not lock the converter at all until 3rd gear at about 50 mph.
I can’t figure out what to do next IF the converter comes back and doesn’t fix the drivability issue….any thoughts about what to do?
SDB
Car was running fine, changed plugs, changed oil and filter, tranny fluid and filter, cleaned nitrous filter, new fuel filter, did front brake pads, polished out headlights…
Drove fine, had nitrous in the line (didn’t race anyone that night), shut the bottle and hit the button (ran hard for a second, then flooded with fuel), check-engine light came on, drove it for a few minutes to clear everything out, light went out, felt fine. Next day, too friend for a ride, ran weird, idled high, very unresponsive, rpm’s came up real slow (like an ultra tight converter or something)…tried it on and of the bottle, same response until above 5,000 rpm, then the rpm’s came up faster. When driving, car would accelerate on its own all the way to 45 mph or so and stay there (from a dead stop with no gas being applied), when shifting into neutral at 45 mph, the rpm’s would climb to 1500 or so, and then slowly fall. If you hit it on a 40-50 roll, it would accelerate slowly until 5-5500 rpm then it would pick up speed.
Here is what I have done (unsuccessfully) to address this problem:
Disconnected/reconnected battery after every change-
Replaced IAC with another IAC from a good running, same year Camaro
Cleaned IAC
Replaced TPS
Checked for intake leaks with carb cleaner (none found, no surging at all)
Autotap- no codes
Snap on scanner- no codes
Had friend rev engine to 1800 rpm or so, disconnected IAC (per mechanic friend), car was more drivable down low, did not want to idle high or go to 45 mph on its own, but still felt sluggish (again like a ultra tight converter)
Went to Livernois to have car re-tuned…used a brand new ECM, did the tuning, made good power (dyno pulls were at 70 mph and above) made 580 rwhp and 644 tque so engine is not damaged, and everything ran great on the dyno-
Test drove it and the exact same problem as before with drivability. Tried replacing Metco breather with standard oil cap, seemed to help lower the idle a little but no major difference. Put foot on brake and foot on gas…floored gas…rpm’s went to 1800 at WOT on the brake, did not go above 1800 rpm’s or spin tires. At this point I thought the converter was bad, drove back home and shipped it to P.I. for a check. Everything checked out fine, they are restalling and sending back to me this coming week.
Having mechanic check intake gaskets for possible leaks, do a compression test, and putting 3.42 gears in rear end, and sending computer back to Livernois for gear swap. I believe the computer is now set to not lock the converter at all until 3rd gear at about 50 mph.
I can’t figure out what to do next IF the converter comes back and doesn’t fix the drivability issue….any thoughts about what to do?
SDB
10-08-2004, 09:14 PM
#2
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hey bro the first thing you do is not go back to livernois motorsports for anything . they dont even have the right software to tune your car. they are using some back *** version of digital horsepower screwed my car all up if ya want the car done right contact wheel 2 wheel,or hardcore bro your at a mustang camp they,ll tell you that there ls1 program is up and running well bro thats bullshit.take your losses like i did and go to a respectable ls1 ls6 camp
10-10-2004, 11:40 AM
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with the engine off remove the two covers off the fuse centers under the hood.Turn the ignition switch to on without the motor being started.Remove the P.C.M. ign. fuse and the P.C.M. batt fuse wait 60 seconds turn ignition off. Wait 60 seconds replace fuses and start engine. This clears all codes and lets computer re-learn idle.
10-10-2004, 11:57 AM
#5
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where do i start,my car is a 98 and has the old style computer 99 and up are updated.The tuner there greg seems to be very capable if he were to use ls1 edit with wide band.Rather than digital horse power that himself and a few other locals are trying to develop at the expense and inconvenience of the ls1 ls6 owners.The software doesnt have the capabilities to turn off torque management,cat delete,air pumpdelete,they couldnt even get the shift points right. I can go on and on but i wont. I go to milan on friday nights.my car goes 10:50 without a cage they threaten me to ban me if i do it again.Gotta get a cage this winter.Come on up and llets talk and race.People will be impressed with your car. The ls1 carsare mostly behind us with very few out front.Red 98ss with licsense plate SOLOCAM.Have fun and look forward to meeting you and your car.
10-10-2004, 01:56 PM
#6
Some friends went to Milan, said it was good time. I will get up there if I can get my car figured out. I have heard bad and good things abou livernois tuning, but the same for all tuners (APE, etc). They got the TM delete done ok, I will try the battery reset thing when I get all buttoned back up. Where did you go for your tuning?
SDB
SDB