please help!!!!
05-02-2010, 01:10 PM
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please help!!!! (93 LT1, pcmforless chip, turbo 400)
Car was working fine then all of a sudden I went to turn it on and started having issues with it staying on (at idle). I can keep car on with foot on paddle, but headers turn red after 30-40 seconds of the car been on. I figured it was the dreaded opti, we took it apart and it checked out OK. Then I decided to go over all the grounds and wiring to the 6AL, everything checked out OK as well. Plug wires were checked, to make sure they weren't crossed, changed plugs and problem continued. Car will turn on but won't stay on at idle and even at high RPMs you can hear its missing. No trouble codes at all, so by process of elimination I decided to checkout the ECM. To my surprise when I took it out of the car and opened it I saw the prom (chip) was loose and the car had basically been running on the stock chip only. I was happy to see that, thinking that just by reinstalling the prom on the computer I would have the problem solved. No luck, so I figured that when the chip was jumping around in the computer it must have caused some damage on the computer itself. I located a 93 lt1 ecm after a week longs search, figured problem solved but unfortunately problem continues. Any suggestions will be greatly appreciated.
*fuel pressure OK,
*I replaced the in tank fuel pump, just in case
Car was working fine then all of a sudden I went to turn it on and started having issues with it staying on (at idle). I can keep car on with foot on paddle, but headers turn red after 30-40 seconds of the car been on. I figured it was the dreaded opti, we took it apart and it checked out OK. Then I decided to go over all the grounds and wiring to the 6AL, everything checked out OK as well. Plug wires were checked, to make sure they weren't crossed, changed plugs and problem continued. Car will turn on but won't stay on at idle and even at high RPMs you can hear its missing. No trouble codes at all, so by process of elimination I decided to checkout the ECM. To my surprise when I took it out of the car and opened it I saw the prom (chip) was loose and the car had basically been running on the stock chip only. I was happy to see that, thinking that just by reinstalling the prom on the computer I would have the problem solved. No luck, so I figured that when the chip was jumping around in the computer it must have caused some damage on the computer itself. I located a 93 lt1 ecm after a week longs search, figured problem solved but unfortunately problem continues. Any suggestions will be greatly appreciated.
*fuel pressure OK,
*I replaced the in tank fuel pump, just in case
05-02-2010, 02:41 PM
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Problem with the 6AL itself? What is the timing...have you checked to make sure something isn't off there maybe between the 6AL and ECM? Are all the injectors firing properly? What is the mileage on the car/majority of the components stock remaining?
05-02-2010, 03:44 PM
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*Disc 6AL and problem continues, I even tried a buddy’s 6AL and problem continues.
*I have followed each wire from 6AL to computer and to coil as well and no problems there either.
*Injectors have checked out ok.
*car has about 30 passes at local track on new 383, rarely on the road.
* zero deck 93 LT1 383 w/ cc306, SRP forged pistons, PCMforless tune, ported LT1 heads w 2.02/1.6, Accel 30 lbs, long tube Pace Setters 1.75, all electrical MSD, 6AL with 3step, throttle body BBK 58 mm, Rail mount Aeromotive Adjustable regulator, AC & EGR eliminated, Meziere electric water pump, Walboro in tank fuel pump, Nitrous Works 150 plate shot, SLP line lock, reverse patterned turbo 400 w 4500 nitrous stall & trans brake, transmission cooler, Griffin radiator, 12 bolt Moser with 4.10s, Sophn suspension, rear battery relocation.
Last edited by black chief; 05-02-2010 at 04:12 PM.
05-02-2010, 06:23 PM
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Maybe test the TPS...could be something going on there with a dead spot...MAP as well. Try and test these before just replacing them if you can. I don't have the procedure off hand...shbox.com should have a lot of these tests though and specs for where the TPS voltage should be for what positions...graphing the TPS would be best to see if there is a dead spot or if the thing is out of adjustment. Neither sensor is terribly expensive, but if they are not the problem, then you end up wasting more money that could have gone toward the actual problem.
