76 Eldo 500 FI Problems

EldoradoRich · #1 (**permalink**) 12-03-07, 02:23 AM

I just realized I posted this in the wrong forum. Sorry. I'll repost it.

I recently bought a 76 Eldorado Convertible with the 500 Fuel Injected engine. I LOVE this car, but it hesitates from a stop, and sometimes idles very roughly for no apparent reason. I've replaced the Throttle Position Sensor, the coolant temp sensors (2), both fuel pumps and filters, all the fuel lines, had the gas tank relined, replaced the EGR valve, replaced all the vacuum lines, replaced all the hoses and belts, all the spark plugs and wires. Compression test and timining check out OK. But the car still hesitates very badly when starting from a stop, although it runs great at speed, especially on the highway. And recently is has had trouble starting after it's been running for awhile. It just cranks and cranks, and crank, and never catches. If you let it sit for an hour without trying to start it, it then starts right up without any problem. Any help at all would be greatly appreciated as I'm running out of things to replace!! Thanks guys!

awadecki · #2 (**permalink**) 12-03-07, 03:26 AM

If it has trouble starting when warm, you might want to check your fuel pressure regulator. That could be leaking. Or, a leaking injector.

carnut · #3 (**permalink**) 12-03-07, 10:50 PM

The TPS , as you know is adjustable. This is from memory, so bear with me!! With key on, engine off, slowly rotate the throttle from idle to wide open throttle. You should hear distinct electrical clicks from the TPS. I believe it is 16 clicks from idle to wide open. If the TPS is misadjusted, there will be a fuel delivery delay at tip in throttle. If it were me, I would move the TPS so the first click occured with just a slight opening of the throttle then road test it. Also advancing timing 2 degrees could help. Also the idle speed screw in the front middle of the throttle body can be turned out ever so slightly to slightly raise the curb idle. Locate a manual on this car or the 76 thru 79 Seville which has the same exact system with smaller injectors. Hope this helps. Merry Christmas!!

awadecki · #4 (**permalink**) 12-04-07, 01:36 AM

Wow. Only 16 clicks. That's old school!

capcw · #5 (**permalink**) 08-30-08, 07:39 PM

there is an exhaust gas port, part of the emissions crap, that may be clogged under the throttle body, and if so will cause it to get hot - might be part of the idle / startability prob.

carnut · #6 (**permalink**) 08-30-08, 08:00 PM

This is an 8 month! old thread. I think the guy either died or fixed it without telling us?