: Rough idle



Eldo~AF
10-15-04, 07:58 AM
I have a 94 Eldorado w/110,000 miles on it. Just replaced plug and wires. My problem is that sometimes at idle the car is very rough. If it is in gear it jerks really bad. But it doesnt always do it. and once at speeds above 8 mph, it doesnt do it. When it does it the SES light comes on. I took it to a mechanic for an unrelated problem and he said it was probobly the computer. What should I replace next? I dont have money to throw at it. Is there any tricks to see if anything else could be the problem? I was thinking maybee fuel filter or injectors may be dirty, also possibly the phenalic spacing, but I dont have much experience with those. Any thoughts would be appreciated.

BeelzeBob
10-15-04, 01:02 PM
I have a 94 Eldorado w/110,000 miles on it. Just replaced plug and wires. My problem is that sometimes at idle the car is very rough. If it is in gear it jerks really bad. But it doesnt always do it. and once at speeds above 8 mph, it doesnt do it. When it does it the SES light comes on. I took it to a mechanic for an unrelated problem and he said it was probobly the computer. What should I replace next? I dont have money to throw at it. Is there any tricks to see if anything else could be the problem? I was thinking maybee fuel filter or injectors may be dirty, also possibly the phenalic spacing, but I dont have much experience with those. Any thoughts would be appreciated.

First place to start is to diagnose the problem.....

With the key on, simultaneously press and hold the OFF and WARMER buttons on the climate control panel to activate the onboard diagnostics and see what trouble codes show up. That is likely to provide a clue as to what is happening.

Find a mechanic who understands the onboard diagnostics and has the proper service manuals/material. Throwing parts at the problem will get expensive and will not likely be very constructive.

smulcahy7494
10-15-04, 05:44 PM
I have a 98 STS and it does the exact same thing. I replaced the filter and the plugs and it is the same. The only difference is I dont know how to get the codes on the newer models. The only thing I could find is a misfire code, but there are two more that they said are dealer specific.

Pjs
10-16-04, 11:22 AM
Do yourself a huge favor and order yourself a factory service manual. You would not believe the amount of information contained in dianostics, not to mention it will pretty much tell you the complete operation of the engine and everything in it. New ones are a little pricey @ just over $60 a volume (mine requires 2 vols), however some companies sell used one's, books4cars.com is where I got mine for $44. It was used but the only way you'd know someone else owned it was his name written inside the front cover. I have read my powertrain manual cover to cover and found this book to be way more intriguing than any novel :D . Seriously though, if you posess any sort of mechanical apptitude and common sense and can't afford to have your car repaired by a local shop than these books are not only a great investment but a must.