HT4100 4.1, 4.5, 4.9 Discussion, Rough Idle on low mileage 91 Eldorado in Cadillac Engine Technical Discussion; Help please! The car is a 91 Eldorado that I just picked up with 20k on the clock. It hadn't ...
Automobile(s): 1991 Eldorado Biarritz, 1991 Sedan Deville
Black Hills, SD
Rough Idle on low mileage 91 Eldorado
Help please! The car is a 91 Eldorado that I just picked up with 20k on the clock. It hadn't been driven more than 100 miles in the last 2 years...old gas etc. The previous owner had a Caddy dealer do a fuel injector cleanse in Oct of 2010 after that it sat again until last week. It is all original under the hood (including plugs and wires). It runs out very smoothly as we took it for a 400 mile exercise this past weekend. I put a fresh tank of premium along with some sea foam in it and got about 25-26mpg on the highway. But...it just sounds too rough at idle. I thought that it was possibly in the exhaust. The exhaust shop said the cat and muffler were fine (I had them replace the muffler anyway...no real change.) Anyway, I've got a new set of OEM plug wires and have ordered rebuilt bosch injectors...was getting ready to order rotor, cap and coil, then thought that before I went any further, I'd see if the pros thought I was on the right track or not? I did clean the egr tube with no change. Any help would be appreciated! Oh, I get a little bit of a gassy smell (not noticable inside, just when outside of car when running at idle or when first shut it off and exit.) I just want it to run like it looks, as it looks like new in and out from its perfect leather to it original tires. Thanks!
Automobile(s): 1993 Coupe Deville 2006 XLR Infrared, Ebony
Orange County, CA
Re: Rough Idle on low mileage 91 Eldorado
I'd run some tests before buying anymore parts. Did you check for codes? Check your fuel pressure and pull the vacuum hose from the fuel pressure regulator, see if it is wet or dry. With only 20k there shouldn't be much wrong with it yet, but rubber tends to deteriorate. BTW, nice looking Eldorado, we all wish our Caddy only had 20k on the odometer.