LS1 Edit Tuning Problems
Thread Starter
Teching In
Joined: Nov 2002
Posts: 45
Likes: 0
From: Dublin, Ohio
LS1 Edit Tuning Problems I recently installed a Hotcam in my 01 TA. A friend in my local club is helping out with the LS1 edit tuning. The part throttle and WOT tuning seem to be dead on now. The problem we are having is with the idle tuning.
Basically it seems to be very hit and miss. Sometimes I can reach through the window and fire it up with no problem. Other times, I have to give it some gas for a few mins to help find the idle and hold it. I also have to let my car sit for a good 4-5 mins idling before I can put it in drive or reverse without stalling. This does not matter if it was a cold or hot start... both are very unpredictible.
I am also having a cruse effect when letting off the gas and a bit of cam surge when coming to a stop. We unpluged my IAC and went for a trip around the block and those problems seemed to go away... strange. Does anyone have any ideas? Thanks!
Basically it seems to be very hit and miss. Sometimes I can reach through the window and fire it up with no problem. Other times, I have to give it some gas for a few mins to help find the idle and hold it. I also have to let my car sit for a good 4-5 mins idling before I can put it in drive or reverse without stalling. This does not matter if it was a cold or hot start... both are very unpredictible.
I am also having a cruse effect when letting off the gas and a bit of cam surge when coming to a stop. We unpluged my IAC and went for a trip around the block and those problems seemed to go away... strange. Does anyone have any ideas? Thanks!
TECH Senior Member
Joined: Nov 2001
Posts: 7,036
Likes: 1
From: Lake Zurich, IL
scale down the Main VE table from 0-1200 RPM ... try a scaling factor of say 85% first , if its still a little choppy restore to stock and try 80% etc...
I've got mine scaled down ~75% and the car never dies on me (382 with a G5X2 equivalent cam in it, 112 LSA in an auto) ... it'll surge a lil on me but not bad at all
Also you may have to raise your idle speed a little... if you do this, atap the car and watch the IACs if they're pegging then you're not getting enough air in and need to make the idle hole slightly bigger in the TB
I've got mine scaled down ~75% and the car never dies on me (382 with a G5X2 equivalent cam in it, 112 LSA in an auto) ... it'll surge a lil on me but not bad at all
Also you may have to raise your idle speed a little... if you do this, atap the car and watch the IACs if they're pegging then you're not getting enough air in and need to make the idle hole slightly bigger in the TB
TECH Apprentice
Joined: Nov 2001
Posts: 387
Likes: 0
From: South Elgin, IL
Just like Horist mentioned, you'll need to work on your VE table. NoGo has a great write-up for tuning after a cam. You should find a copy in here if you do a search. You can also check out LS1Tuning.com.
You might also have to add some timing to your lower RPM's. That helped my idle quite a bit. I'm still fine tuning my cold starts but I've just about gotten rid of all the surge.
Don't drill. Instead just give the idle screw a little turn to crack open the blade. Then reset the PCM. Double-check that your TPS reads 0% at idle.
TIP - The screw is a Torx and it can be difficult to get to with a Torx bit. Some people remove the TB to get to the screw. Here's a much easier way. Use a small allen wrench to turn the screw. I can post later what size allen wrench works.
You might also have to add some timing to your lower RPM's. That helped my idle quite a bit. I'm still fine tuning my cold starts but I've just about gotten rid of all the surge.
Don't drill. Instead just give the idle screw a little turn to crack open the blade. Then reset the PCM. Double-check that your TPS reads 0% at idle.
TIP - The screw is a Torx and it can be difficult to get to with a Torx bit. Some people remove the TB to get to the screw. Here's a much easier way. Use a small allen wrench to turn the screw. I can post later what size allen wrench works.
Thread Starter
Teching In
Joined: Nov 2002
Posts: 45
Likes: 0
From: Dublin, Ohio
Thanks for the replys! We have tried the above and still are having problems. The next thing I am going to try is the idle relearn procedure. I am stuck working till Sunday... so I will try it then. Thanks for the input.
TECH Apprentice
Joined: Nov 2001
Posts: 387
Likes: 0
From: South Elgin, IL
The allen wrench I have sitting in my car's cup holder doesn't have the size stamped on it but I would guess it's around 3/32".
I used NoGo's 60-80-90 VE table tweak but had to go back and take out less. I ended up with something like 75-90-95.
I'm running a TR230 cam with a 110 LSA.
I used NoGo's 60-80-90 VE table tweak but had to go back and take out less. I ended up with something like 75-90-95.
I'm running a TR230 cam with a 110 LSA.
