: 94 Eldorado rough at slow speeds

12-31-04, 03:36 PM
If the weather clears tomorrow I'll run some codes but for now---- I've noticed that my Eldo runs kind of rough at slower speeds, say up to 35 mph. At highway speeds it runs like a dream. Last night I was caught up in stop and go traffic for about 15 minutes then drove on back, winding roads for about another 15 minutes. My service engine soon light came on and the car was running a little rough. When I got back on the highway at speeds up to 80mph it ran great. The service light stayed on. This morning I started up and went for a short ride and the light was out and hasn't come on since. I know everyone here says running "regular" 87 octane gas is no problem but this all seemed to have started when I switched to the lower octane. Any ideas ??

01-02-05, 11:38 AM
I ran the codes this morning. Only codes listed as current are P061 and P065 both of which refer to the Cruise Control, which has not worked since I have owned the car. When I started the car this morning I got a message "NO BATTERY CHARGE". I checked the info center and it read 14.6 volts. The warning went away as soon as I put it in drive. I kept watching the battery reading and it stayed between 14.5 and 14.8. Also, the battery is only three months old. I just took it onto the thruway and blew the hell out of it. Everything runs great at higher speeds but once again when I got into stop and go traffic she starts running rough again. Anyone got any ideas ???

01-02-05, 11:45 AM
plugs and wires? How many miles on it? Many on here have had the rough running complaint with original wires that were disturbed for a fuel rail replacement...seems they get frail and when they are bumped, they start to run pretty bad...us only AC Delco plugs and wires, as they are by far the best available...and this problem only showed up at part throttle and idle for many people, but at higher speeds and wot, they would run fine...I don't know if thats your problem, but its worth looking into as a cheap and easy fix.

01-02-05, 11:56 AM
Had new plugs and wires replaced same time I had a new battery, about three months ago. Cost me $500+ dollars so would hope they put good quality parts. I've got 120,000 miles and other than this rough running problem I have no complaints. Think I'll go back to the Premium fuel and see what happens.