LT1 problems
05-20-2005, 03:05 PM
#1
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Location: Indianapolis
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LT1 problems
ok so we have an LT1 in our 83 malibu wagon, it has never ran
full opti is brand new, new coil pack, new painless wiring harness, new plugs and wires. turns over fine, has no spark though, i took out the sparkplug and i can visualy tell it has no spark. any suggestions?
full opti is brand new, new coil pack, new painless wiring harness, new plugs and wires. turns over fine, has no spark though, i took out the sparkplug and i can visualy tell it has no spark. any suggestions?
05-20-2005, 04:12 PM
#5
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Posts: 1,362
Re: LT1 problems
Is it those $15 chips on ebay? I'd double check the wiring and I had a buddy break 3 of those, they just shorted on him after every two days. I'd have VATs programmed out. Is the fuel pump priming? Injectors firing? If not, its vats.
05-20-2005, 04:19 PM
#6
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Re: LT1 problems
fuel pump is good, i pressed the thing on the fuel rail and its presurized, and i can hear the pump going. how do i check if the injectors are working? its been quite a while and its possible the injectors are also not squirting, but there is deffinatly a spark issue, ie none
05-20-2005, 04:28 PM
#7
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Re: LT1 problems
Basically if you smell gas while trying to start it his I always know. Also if your plugs aren't sparking, pull one out and it should smell like gas. If its dry their not firing. Is the fuel pump going to the PCM or is it going to power when the key is turned? If its going to 'power when the key is turned' you can't tell if its vats. If its going to the pcm and the pcm is grounding it, vats is not a issue.
05-20-2005, 05:54 PM
#8
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Re: LT1 problems
not sure exactly what that ment, but the fuel pump is on a toggle switch
someone told me that LT1s dont have chips in the comptuers also
so it is probably the VATS then that is keeping it from sparking?
someone told me that LT1s dont have chips in the comptuers also
so it is probably the VATS then that is keeping it from sparking?
05-20-2005, 06:29 PM
#9
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Re: LT1 problems
Yes, and you telling me its on a toggle switch tells me the PCM is not controlling your fuel pump. Im pretty sure your issue is with VATS. Thats correct on no programmable PROMs on the ECM's except the 93 lt1's out of f-bodies (maybe the 92 vettes too, dunno). You can still have your pcm programmed and its far better than proms. Check out www.madz28.com
05-22-2005, 02:41 AM
#13
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Location: LA (lower Alabama)
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Re: LT1 problems
Do you have 12V to the coil with the key on?If not put a 12V wire direct to where the 12V supply is and see if it will fire.Ya need a wiring diagram to make sure it is the right wire. Disconnect the 12V wire from the harness that's in the plug in so no damage will occur if something is connected wrong.At that point it is only feeding the opti.
Do you have a '93 PCM and a '94 or later engine or wiring harness?
Maybe Inguneer or some one smarter than me on computers can chime in and give advice on the difference in the computer system and what will work with what.
As mentioned above the VAT is a very likely option.
Do you have a '93 PCM and a '94 or later engine or wiring harness?
Maybe Inguneer or some one smarter than me on computers can chime in and give advice on the difference in the computer system and what will work with what.
As mentioned above the VAT is a very likely option.
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