Hello all, first post here. I have been lurking for 3 months attempting to solve various problems that my girlfriends "new" Cadillac has. It is a clean 1989 fleetwood from palm springs, previously owned by snowbirds- people who live in Canada and come to palm springs during the winter. It has had 3,000 miles put on it since 2001, needless to say it is in fairly good shape with 104,000 miles. A brand new alternator is on it, and upgraded air conditioning hoses (it gets HOT in palm springs).

The history since I started a few months ago (I have an FSB):

The car initially wouldn't start unless you pumped the gas pedal while turning the ignition, also wouldn't really go forward when you pressed on the gas. I did a "tune up"- replaced distributor, rotor, spark plugs, wires, cleaned throttle body, new air filter, cleaned all air hoses, inspected for vacuum leaks around the throttle body- attempted to align the ISC to .60? gap. This all made the car nice and spritely- tires spin when you punched it at 10 mph, but my girlfriend would have the car just shut off on her in traffic out of no where- sometimes when turning, and braking at the same time. Also when the car was warmed up, you could just turn the key and it started- when its cold you still have to press the gas to get it to start.

I decided it was the TPS/ ISC- the dash code was e55? saying issue with the TPS. We brought it to a mechanic- someone with long time cadillac / GM experience. He instantly saw that the ISC motor wasn't working, when you turn the key slightly he said it should extend fully with the pintle then come back and learn the idle. This wasn't moving at all. He replaced the ISC valve with aftermarket (said he couldn't find ACDelco- even though rock auto has acdelco isc for my year car??) and the aftermarket was crap. Worked worse at the end of one drive, he put in another aftermarket- much better, however serious chugging up hills now, when you punch it it will search/feel like its misfiring. So we have a new ISC that works properly.

When I did the tune up I did rock auto's tune up kit- which had standard rotor/distributor and ngk iridium plugs. The mechanic said I should just use ACdelco, so I've ordered that and am waiting on the shipment- this week, to see if the plugs /rotor/distrib have something to do with it chugging.

Now with the new ISC valve, it only stalls when she doesn't warm up the car. When the mechanic worked on it- he found that the fuel filter was installed opposite, he switched it back. The fact you can't start it without pressing on gas peddle- is it a gas issue? or just letting air into the engine to start/ TPS issue?

Anyone have any ideas on what to check? I'm planning on opening/cleaning the EGR valve, I am new to GM cars- have only experience on german/japanese cars, these spark plugs are a royal PITA to do !! That being said there is nothing like riding down the road, so comfortable and peaceful...a great car!

Thanks, I tried to do everything I could by lurking but sometimes you've got to give in! Also need help with a very noisy buzzing speaker and the drivers door window won't move...Would going to mostly LED lights require less power and help the engine drive??? There are a LOT of lights on this car! Could I go to a larger battery without problems?

Added some photos of when we first got it/ I began cleaning road grime off engine.