1989 Cadillac Deville stumped

1989 CADILLAC DEVILLE
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TJEFF74
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Engine Performance problem
1989 Cadillac Deville V8 Wheel Drive Type unknown Automatic 184,00 miles
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We have tried everything we can think of to fix this car! It runs really rough, and it dies at the stop light, it idles really high, and makes a ton of noise. We have changed O2 sensor, alternator, fuel pump, cap roter, spark plugs, battery, ALL to no avail. Nothing helps it still acts the same way. Theres no codes coming up, no check engine light either. Do you have any suggestions?
Mar 11, 2008 at 1:29 PM
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BUZZSAW
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[quote:1ee6e6a5c2="tjeff74"]Engine Performance problem
1989 Cadillac Deville V8 Wheel Drive Type unknown Automatic 184,00 miles
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We have tried everything we can think of to fix this car! It runs really rough, and it dies at the stop light, it idles really high, and makes a ton of noise. We have changed O2 sensor, alternator, fuel pump, cap roter, spark plugs, battery, ALL to no avail. Nothing helps it still acts the same way. Theres no codes coming up, no check engine light either. Do you have any suggestions?[/quote:1ee6e6a5c2]

there has to be codes, how are you reading them?

what is the engine size? 4.5?

push off and warmer on the heater controls, with key in the on position, starts out 8.8.8 and ends with 0.7.0. write them down and post them here

sounds like to me your throttle angle is off throwing the TPS off, which throws off the ISC motor, making it Idle high
Idleing rough:
what about plug wires
have you checked the Injectors with an ohm meter, should be about 12-13.5 ohms
if all thats ok replace the computer
Mar 14, 2008 at 12:54 AM