I'm a brand new member, great forum, lots of knowledge out there!

My 16 year old son and I bought him a 98 Catera with 97K on it a few months ago. It's so sweet that I was actually a little jealous, his buds in their Acura's and Lexus's were just as jealous. My daily driver is a 2003 F150 Lightning pickup, for those of you that don't know, they are really quick, but suck in the snow with the P295 "skis". So, I was somewhat jealous of my son, and wanted a "winter car". As it happened, less than two weeks ago, I stumbled across a 1988 Eldorado, 4.5L, with 98K one owner miles for a fair price. I bought it from the grandson of the deceased original owner who claims it has pretty much sat for 8 months since his grandad died, before that always garage kept and serviced by the local dealer. The body is near perfect, no dents, repairs or rust; interior fair with some stress cracks in the leather and a crack in the armrest. All in all, the car looks near original mint. The problem is the engine runs "rough", and that's why I'm here, so enough rambling on.

After a thorough cleaning and detailing, oil and filter change, and running a fuel system cleaner through the intake, I began driving it to get to know it better. The 3rd day I drove it, antifreeze was running all over on my way to work one morning. I topped it off and got home with no overheating problems and put a new waterpump on it last weekend.

The engine idles rough, doesn't stall; it lacks power and misses when accelerating, especially under load; then occassionally straightens out and shows off it's considerable power. It's done this from the day I test drove it, and doesn't seem to me to be internal, i.e. compression, valves, head gasket, etc. I suspect more electronic, emission control or fuel, possibly from the ECU. Oh yeah, and one other thing, the cruise shows "set" on the digital dash, but doesn't work (just like JeremyG's post).

Thanks to this website and a couple of others, I figured out how to tap into the OBD. Not sure I understand all but the obvious, and was hoping some of you can help me out. This is what I know via the OBD codes:

E030- ISC RMP OUT OF RANGE
E052- PCM MEMORY RESET

I have some ECM data, but as I read it, nothing stands out.

I also have some ECM OVERRIDES:

VCC SOL ES01
EGR SOL ES02
ISC MOTOR ES03
C/C SERVO ES04

Does this mean these codes have been overridden to take them out of the code history and not fault? My guesses included EGR and ISC with symptons, and it does downshift erratically when missing/sputtering under acceleration (VCC?), and I already mentioned the cruise (C/C?) don't work.

Does anyone know how to get these UN-overridden? If I do and they show up again should I replace the VCC solenoid, the EGR valve, and the ISC motor and inspect or replace the CC servo?

Any advise would be greatly appreciated. I'm lookin' good in this Eldo, but need to get the powerplant smoooooothed out.

Out,
EldoBoy

I guess if it sat for 8months+ it would have bad gas... Have you driven most of the old gas out of it? If it still does it after some new gas I'd look into possibly clogged injectors then bad spark plug(s), the timing, then the TPS sensor... I'd look into getting it to idle properly before looking into the drivability problems...

Did you feel the tension in the timing chain when you had the waterpump off? was that loose, Ive heard that right before the chain goes you'd get a rough idle...

Thanks for your response 89eldorado.

Gas is fresh, working on my second tank. I am going to throw a couple bottles of Heat in the tank just in case there may be moisture/condensation. I'll be honest with you, I've had moisture in gas before and the symptoms are very similar. That's another thing, mileage is in the low 14's and I would expect something more (16-17) with at least half freeway miles.

I thought about plugs and wires, but the wires look new (definitely not originals) so I assume the plugs are fairly new too. I need to talk to the dealer where this car was serviced to see if they will provide me with records (assuming the seller was giving me the straight scoop). Shame on me for having not done that yet. It's on my list. Not to say that new plugs might be worth a try, but those bad boys reside in no-man's land in this Eldo. Doesn't make sense to me that plugs would shake loose and run fine on occasion, so that brings me to the injectors...

Got any tips on "checking" the injectors outside of replacing them? Don't get me wrong, if I knew that was the problem I'd throw out a couple hundred bucks and replace 'em, but I'd like to know that was the problem first.

The timing chain isn't visible with the water pump off. I didn't know enough to reach inside the block cavity to check the timing chain when I replaced the water pump. Wished I had if you can feel it, as that could be at least part of the culprit.

Thanks again!

The symptoms sure sound like ignition. Have you checked the inside of the distributor cap and the rotor? You might try using a spray bottle with water to mist the wires at night to look for arcing.
Also check out item #7928383358 on Ebay.
FWIW
YMMV
DFB

DFBonnet, Thanks for your reply. I haven't completely ruled out ignition but as luck would have it we've had some very damp cool weather this week and NO difference from the very dry weather of a week or so ago. Cap and rotor "looK" to be fine (again appear to be recently replaced) but indeed would be a cheap-and-easy trial and error item and I will go there.

I'm already on that eBay item and am watching a couple others just in case I get out bid in the next 50 minutes.

THANKS!
EldoBoy

The items you mention as codes are not codes and nothing is being over ridden.... Those are just prompts in the diagnostic system.

The timing chain and such should be fine as that engine had a very robust chain and a steel timing gear on the cam (not the nylon toothed one) so it will run a long long time.

Watch the injectors at the TBI to see if both are firing and if the spray cones are similar. You can see them using a timing light as a strobe light. Disconnect the wires to the injectors and crank the engine and watch the injectors for any sign of fuel delivery. If there is any, then that injector is sticking or leaking as they should not deliver any fuel when the wires to the injectors are disconnected.

Mine also had a rough idle that I tried to fix by installing new spark plugs and new wires to no avail. I ended up pulling each spark plug one at a time while the engine was idling and locating which cylinder was not firing. The spark plug wire that was hooked up to the non-firing cylinder was firing and shocking me just fine so I knew that it was alright. So just for grins, I lowered the gap on that spark plug from .060 to .050 and it now idles very smooth now.