Code 51 help
#1
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Car: 02 T/A
Engine: LS1
Transmission: Built 4L60E
Axle/Gears: 3.42 Posi
Code 51 help
I have an 89 L98 with slight mods. I had a chip made to put in the ecm to delete VATS, EGR, and AIR pump. It has a painless wire harness, is a v6 swap car. anyway, the car turns on and runs, I can drive it around, whatever. But sometimes, the ses light just flickers on and off, the cars rpms start to move sparatically like it isn't getting fuel, then the problem stops and the car runs fine again. sometimes when it does this the car shuts down if I don't put my foot into the gass pedal. when I jumper the ALDL I get a code 51, rarely do i get code 42. 51= prom error 42=Electronic spark module issue. What I have read is sometimes code 51 will cause a false code 42 to show up. (I put in a new spark module when I swapped engines 2 months ago) so, what I am asking is does this mean my PROM is bad?
Thanks!
Jonny B
P.S. the error codes only show up when the car dies not when I shut it off after it has started running fine again.
Thanks!
Jonny B
P.S. the error codes only show up when the car dies not when I shut it off after it has started running fine again.
#2
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Car: 1990 GTA
Engine: L98 350 Dart Heads 268XFI Super Ram
Transmission: WC T5 Hurst Shifter
Axle/Gears: 3.42 Posi
Re: Code 51 help
Hey
Did you figure out your problem?
my car is doing the same thing
Did you figure out your problem?
my car is doing the same thing
#5
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Car: 1990 GTA
Engine: L98 350 Dart Heads 268XFI Super Ram
Transmission: WC T5 Hurst Shifter
Axle/Gears: 3.42 Posi
Re: Code 51 help
Yes I did
It was my moates auto prom, I burnt a chip and unhooked my auto prom and the car runs perfect, so now I don't do real time tuning
It was my moates auto prom, I burnt a chip and unhooked my auto prom and the car runs perfect, so now I don't do real time tuning
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Car: 1990 GTA
Engine: L98 350 Dart Heads 268XFI Super Ram
Transmission: WC T5 Hurst Shifter
Axle/Gears: 3.42 Posi
Re: Code 51 help
It didn't cost me anything because I have the tools to do it myself, I think you need to check the connection between your piggy back, chip and ecm, make sure they are tight and not loose (I bent all the little tangs on the ecm that plug into the piggy back a little to the left so they fit tight), but be very careful doing something like that. Also check all your ecm grounds and that your connectors from the car to the ecm are tight and make a good connection.
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#8
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Re: Code 51 help
It didn't cost me anything because I have the tools to do it myself, I think you need to check the connection between your piggy back, chip and ecm, make sure they are tight and not loose (I bent all the little tangs on the ecm that plug into the piggy back a little to the left so they fit tight), but be very careful doing something like that. Also check all your ecm grounds and that your connectors from the car to the ecm are tight and make a good connection.
#10
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Car: 02 T/A
Engine: LS1
Transmission: Built 4L60E
Axle/Gears: 3.42 Posi
Re: Code 51 help
I replaced my whole chip with a new one from ACDelco and it still does the same thing...
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Car: 2003 Hyundai Tiburon GT
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Re: Code 51 help
I'd have to check on this in the morning, as my FSM is in the garage, but I believe DTC 51 isn't necessarily a PROM error, as is stated around the Web. IIRC, DTC 51 means "Cylinder Select Error" and can be caused by a wire at the ECM that is in the wrong hole... This wire tells the ECM whether the engine is a 6 or 8-cylinder based on which hole it's in. As I said before, I'll check on this.
#14
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Car: 02 T/A
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Re: Code 51 help
I am hoping it is the ecm... I really don't wanna eff with the harness... again...
#16
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Re: Code 51 help
I'd have to check on this in the morning, as my FSM is in the garage, but I believe DTC 51 isn't necessarily a PROM error, as is stated around the Web. IIRC, DTC 51 means "Cylinder Select Error" and can be caused by a wire at the ECM that is in the wrong hole... This wire tells the ECM whether the engine is a 6 or 8-cylinder based on which hole it's in. As I said before, I'll check on this.
#17
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Car: 02 T/A
Engine: LS1
Transmission: Built 4L60E
Axle/Gears: 3.42 Posi
Re: Code 51 help
I Didn't have time to wait (my car is my daily driver) Just threw money at the next logical cause of the problem and BOOM. Problem solved. Re-man ECM from Autozone. 77 bucks. She runs like a dream.
Jonny B.
Jonny B.
#19
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Re: Code 51 help
Well I never followed up on this post so I will give a extremely late update on my TC 51. The problem ended up being the Hypertech chip that I had. I sent the PROM to a fellow member here in the boards and he tried to extract the BIN file to make me a new EPROM. Well on his TunerPro, the BIN file was trashed. So this explained that the Hypertech 127062 PROM was bad. So I then contacted another member here on the boards and he was kind enough to burn me a chip with a 87 IROC BIN file for free. All I paid was the shipping and the cost of the EPROM. So as I installed my new burnt chip by using a Moates adapter, my IROC fired up and I never agian got a TC 51. Here is my burnt chip that fellow TGO member hooked me up with http://www.youtube.com/watch?v=qO5YZvWS8I8.
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