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My 93 LX 5.0 5pd just fried the computer which was a A3L. I replaced it with a 91 GT 5.0 computer A9L. The GT is a factory 5spd car but when I bought it she had a C4 in her. With the A9L in my 93 LX the check engine light comes on, rpm's surge and hover around 1000-1500 rpms. I can feel the car hesitate when driving down the road. Since the swap it feels like it is down on power. Is there a problem elsewhere or should I track down another A3L for my 93 LX
 

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The A9L should work in yours, don't change computers yet; let's try to find the reason why it feels different first.
Tell more about the car, in particular how the other computer got fried.
 

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Going down the road and it shut off. Crank no start. Noticed the fuel pump was not shutting off. Changed distributor,coil,ignition module,unhooked MSD,throttle position sensor,new plugs,wires. Still crank and no start. When I changed the computer the car fired up and runs. All parts installed were new.
 

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Never seen an A3L ecu......
Do you mean A3M????????


Are you getting diagnostic codes?
 

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Never seen an A3L ecu......
Do you mean A3M????????


Are you getting diagnostic codes?
Exactly, Vri. Pull the codes, if there is a Problem in the SIGRTN is will show a ton of them. if at any point some one had used a Auto O2 harness on that car, its possble its fried again.
 

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There is a hardware difference between an auto processor & a manual processor. The difference is because of the way the NDS [neutral drive switch, manual transmission] & the NSS [neutral safety switch, auto transmission] are wired. They are both wired to the same pin#30 but the auto trans wiring grounds the pin to the starter solenoid & the manual grounds to signal return, during crank mode there is a voltage spike sent to pin-30 so the auto trans processor has a diode on pin 30 where as the manual processor doesn't, most of the time this won't cause a problem unless you get into a prolonged crank condition.

Those that want to convert their automatics to manuals, and swap the ECM, need to clip the wire going to pin 30 or else the ECM will fry the trace off the board. This leaves the manual EEC unable to dump codes, which looks for the loop through the neutral sensing switch of the T5 transmission.

Make sure you have a 5 speed O2 sensor harness when using an A9L or you will fry the trace also. The damage is common when people mismatch harnesses and use an automatic O2 sensor harness with an A9L computer.
 

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The man ^^^^^ knows what he's doing.
 

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Discussion Starter #8
The car is a 1993 SSP LX 5.0 out of FL. The tag on the inside of the pass side door says A3L and so did the computer when it was pulled. Was there something different for the SSP cars? I am about to rip the fuel injection off and go with a carb.
 

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The SSP cars had different items but nothing related to the engine. I think they had heavier radiators, alternators and stuff like that.
 
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