1990 want to remove limp mode from computer

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Nov 3, 2015 | 05:40 PM

2000jack

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3rd Gear

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1990 want to remove limp mode from computer

I have a 1990 that goes into and out of limp mode when ever it wants and it seems that the memory is not working either. So do I get a knew ECU or replace the PROM chip. Sometimes I go around a hard right hand turn the light comes on, then goes
off. Sometimes driving straight the light comes on then goes off. The light comes on and then restart the motor the light goes off. I don't care about the mileage , horsepower or emissions. I don't care if the light says on.
The last 13 months I put on less than a mile cause of this problem. I
believe that I can pull the fuel injection with the computer off the car and put on a 4 barrel and the car will run, correct? I rather not go this
drastic but I will if I have to I will.

Nov 3, 2015 | 06:01 PM

THE 383 admiral

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1st if you did not have the limp home. you will not use your car at all. I would be looking for a loose connection / frayed wire corrosion Or loose prom carrier. Especially if you are going around a corner. And the ECU - SES light is displayed.

Nov 3, 2015 | 06:11 PM

2000jack

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Quote:

Originally Posted by THE 383 admiral

How is that? The 1989 model (I understand) did not have this limp mode. So why would I need it in the 199o? I have not driven this car more than I mile in 13 months cause it is a pain in you know what. I like what you say about going around the corner and that the prom chip may be loose.

Last edited by 2000jack; Nov 3, 2015 at 06:12 PM.

Nov 3, 2015 | 07:35 PM

c4cruiser

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From: Lacey WA RVN 68-69

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When you refer to the "light" coming on, do you mean the Service Engine Soon light? If so, you need to pull the codes and post them here.

Nov 3, 2015 | 08:02 PM

Churchkey

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From: Cherokee National Forest TN

Light on, shut off motor then restart = no light on restart. This is an EGR symptom a code 32 will verify it.

If the engine shuts off while driving you have a different issue.

Nov 3, 2015 | 08:31 PM

2000jack

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Quote:

Originally Posted by c4cruiser

When you refer to the "light" coming on, do you mean the Service Engine Soon light? If so, you need to pull the codes and post them here.

Yes Check Engine light comes on. That seems to be one problem, as the computer does not hold the codes in storage. Another is it may come on for 200 ft and then go off. It will come on and then shut off the car and it clears and runs fine. Why can't I just get another after market ECU without limp mode. Car run fine till the light comes on, then it sucks, the light goes off it runs fine. I believe I getting bad code readings and that the are not bad , but the computer is bad. It would seem that if I got rid of the limp mode, it would not matter what the codes read cause the motor runs fine.

Nov 3, 2015 | 11:33 PM

Cliff Harris

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From: Anaheim CA

Based on my investigation while laid up in the hospital with lots of time...

It's virtually impossible to get into limp mode. It only happens if the microprocessor stops running or goes into an infinite loop, which theoretically is not possible because the programming interrupts 160 times a second and goes off and does something different.

I don't know what you are experiencing, but it's not limp mode.