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electronic spark timing

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Old Dec 22, 2007 | 09:03 PM
  #1  
thirdgenlover's Avatar
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From: Indiana
Car: 87 trans am
Engine: 350 TPI bored .040 over
Transmission: modified 700r4
Axle/Gears: stock spline, 3.73 Eaton posi
electronic spark timing

has anyone ever had any problems with a mis fire kind of problem where it is so bad that you can actually see the rpms drop on the gauge. its not just a wire or plug because it is like all the cylinders are being effected. Which would explain why i got a code 42 yesterday, which is the est or ignition control module that is under the distributor. Could moisture get in there and cause that? I have had issues with the ignition module before, but the times that i had problems it was when the module just totally went out. as in i started the car and ran it and then it sat for a while and then it wouldnt start back up. So i am use to it just going out not so much working and then not working or as in the signal is cutting out? Please help, its so bad that you can hear it crackling and backfiring thru the exhaust.
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Old Dec 22, 2007 | 09:36 PM
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02 camaro's Avatar
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From: Arvada colorado
Car: 1987 Pontiac Firebird Formula
Engine: 305 T.P.I V-8
Transmission: M5
Axle/Gears: 372's
Re: electronic spark timing

Possibly a full tune up(Hell SOUNDS like you may need a new coil AND distributer?..Correct me if im wrong
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Old Dec 22, 2007 | 09:45 PM
  #3  
thirdgenlover's Avatar
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From: Indiana
Car: 87 trans am
Engine: 350 TPI bored .040 over
Transmission: modified 700r4
Axle/Gears: stock spline, 3.73 Eaton posi
Re: electronic spark timing

ran like a top before i started having fuel issues. Pump went out again, car sat for a while until i got it done. got it all done and got it back out and started having this problem. Distributor is about maybe 2 years old, coil isnt stock, msd one. I had my timing at 8 and i moved it back down to 6 and still issues. all plugs and wires got changed out earlier this year in the summer

Last edited by thirdgenlover; Dec 22, 2007 at 09:49 PM.
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Old Dec 22, 2007 | 09:49 PM
  #4  
02 camaro's Avatar
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Joined: Feb 2007
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From: Arvada colorado
Car: 1987 Pontiac Firebird Formula
Engine: 305 T.P.I V-8
Transmission: M5
Axle/Gears: 372's
Re: electronic spark timing

when was the last time you got new plugs?
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Old Dec 22, 2007 | 09:59 PM
  #5  
thirdgenlover's Avatar
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Joined: Jul 2005
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From: Indiana
Car: 87 trans am
Engine: 350 TPI bored .040 over
Transmission: modified 700r4
Axle/Gears: stock spline, 3.73 Eaton posi
Re: electronic spark timing

this past summer, june or july of this year
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Old Dec 24, 2007 | 06:32 AM
  #6  
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From: Roy,UT USA
Re: electronic spark timing

Make sure you're using an AC Delco ignition module. The cheaper replacement ones that most parts stores sell are far inferior to the original ones. Although it's pretty rare, there is a possibility that the ESC module could be having issues. It's located on the driver's side firewall behind the brake booster. Another thing that can affect the EST circuit is a faulty knock sensor. Probably ought to start by getting the ignition module tested to make sure it's functioning correctly. If that checks out ok, then look into the ESC module and the knock sensor circuit. Also, since you were having fuel issues, you could also be experiencing a lean misfire. Hook a fuel pressure gauge up at the schrader valve on the fuel rail and make sure you're getting adequate fuel pressure.
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Old Dec 25, 2007 | 01:06 AM
  #7  
thirdgenlover's Avatar
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From: Indiana
Car: 87 trans am
Engine: 350 TPI bored .040 over
Transmission: modified 700r4
Axle/Gears: stock spline, 3.73 Eaton posi
Re: electronic spark timing

Pat hall im pretty sure its probably just the est, because when i was having fuel issues, i had a code for the esc then and not now. in my haynes manual it doesnt say that a code for est is related to the esc, but if you have a esc code it could be related to the est. Replaced the esc module when i was doing my pump and no esc code yet. I am currently not sure if im having fuel issue now because i havent been able to test it out yet because the fuel pump would only mess up after the car has been running for three hours. Havent had it running that long since im out of school and dont have to travel. As for now im not having fuel issues, pressure is good too, and also when the car is mis firing its rich, can smell it inside the car.
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