Hot Cam Idle Issue
#1
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Help me, please!
I swap the factory cam on my 97 LS1 with a GM hot cam and springs, after having done all other mods like: fast intake 78 mm, TPIS exhaust manifold, Borla Stinger cat back, Vortex intake, Vinci Maf, ported throttle body, 170° thermostat, adjustable fuel pressure regulator and stage II jet chip.
Before the cam swap the car was great, without any problem, except for some cold star problems whit very low outside temps, but after swapping the cam, we started the engine that idled regularly for about five minutes, then it revved up by itself to about 2-2500 rpm and then it died!!!After then the car couldn't stay at the idle by itself, while revving up above 1200 rpm to 6000 rpm, the engine it's simply fantastic!
It's know that GM says hot cam does not need PCM reprogramming, but some guys told me that it's not quite true... is this the problem, or maybe simply I have to enlarge the hole on the throttle to high the idle ? Or maybe is there something else? I also double checked all the sensors, even the map on the back of the intake manifold, that with the fast one it's not fitting perfectly, but without any positive result...
Help me please!!!!
I swap the factory cam on my 97 LS1 with a GM hot cam and springs, after having done all other mods like: fast intake 78 mm, TPIS exhaust manifold, Borla Stinger cat back, Vortex intake, Vinci Maf, ported throttle body, 170° thermostat, adjustable fuel pressure regulator and stage II jet chip.
Before the cam swap the car was great, without any problem, except for some cold star problems whit very low outside temps, but after swapping the cam, we started the engine that idled regularly for about five minutes, then it revved up by itself to about 2-2500 rpm and then it died!!!After then the car couldn't stay at the idle by itself, while revving up above 1200 rpm to 6000 rpm, the engine it's simply fantastic!
It's know that GM says hot cam does not need PCM reprogramming, but some guys told me that it's not quite true... is this the problem, or maybe simply I have to enlarge the hole on the throttle to high the idle ? Or maybe is there something else? I also double checked all the sensors, even the map on the back of the intake manifold, that with the fast one it's not fitting perfectly, but without any positive result...
Help me please!!!!
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#2
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Yeah, no sh*t, you just swapped out a crap load of stuff.
You need to tune your new setup now for driveability and to get the most out of it power wise.
Take it to a local dyno tuner. If that's not an option, reset your pcm to stock and mail it off (with a list of your mods) to any of the board sponsors who do mail order tuning.
You need to tune your new setup now for driveability and to get the most out of it power wise.
Take it to a local dyno tuner. If that's not an option, reset your pcm to stock and mail it off (with a list of your mods) to any of the board sponsors who do mail order tuning.
#3
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It was what I was afraid of.. I live in Italy and it's not easy for me to do it as for you in U.S. ...
Could you suggest me someone for example, without doing nothing wrong ?
Thank you.
![Cry](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_cry.gif)
Could you suggest me someone for example, without doing nothing wrong ?
Thank you.
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#9
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For the vacuum leaks I have already checked!! It's all right!
Tried also to take apart the jet chip, but the idle was even worse...
Finally I tried to do a larger hole on the throttle and it stays on! Even if not too regular... But thank to your advices I know that I'll have to reprogram the PCM at least for the idle....
Thanks to all of you guys!!!
Tried also to take apart the jet chip, but the idle was even worse...
Finally I tried to do a larger hole on the throttle and it stays on! Even if not too regular... But thank to your advices I know that I'll have to reprogram the PCM at least for the idle....
Thanks to all of you guys!!!
#10
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i'm having this same problem with this cam on my 02 z..... sometimes it will idle for just a few seconds, and other times it will run shitty for awhile then die. i pulled the codes, and it keeps giving me a po-343, which has something to do with the cam sensor.. do i just have a bad cam sensor? or do i need tuning in order to fix it? i did enlgarge the hole in the tb and it runs better... but it keeps dying.