Ok, shes stalling basically when I take my foot off the gas. It'll stumble then cut out. This is getting really frustrating and dangerous when I have to resart it every time I take my foot off the gas.

Another thing - the fuel gauge went from 23L to the "Fuel Level Very Low" warning in an instant! Yet when I filled it up, there was 23L in the tank!

Why am I stalling so much? Need help or else im gonna take it to the dealership andf have them work it over!

There are many things that can cause an engine to stall. Do you have any mechanical knowledge? Have you checked anything yet?
First place I would start is looking for a vacuum leak. A substantial vacuum leak will do what you describe.

There are many things that can cause an engine to stall. Do you have any mechanical knowledge? Have you checked anything yet?
First place I would start is looking for a vacuum leak. A substantial vacuum leak will do what you describe.

UPDATE!!!

I just pulled error code P053 which is Distributor Signal Interrupt.

I will check the cap and rotor to make sure there are no problems there but if there isnt, i'm wondering if the distributor itself it going?

id check all the wires that go to the distributor , maybe theres a loose connection somewhere or some corrosion inside the plug in connectors

distributors are expensive id make sure all the wires are ok to and from the distributor , and maybe check the sprak plugs wires too ,

do these distributors have "modules" ?

id check all the wires that go to the distributor , maybe theres a loose connection somewhere or some corrosion inside the plug in connectors

distributors are expensive id make sure all the wires are ok to and from the distributor , and maybe check the sprak plugs wires too ,

do these distributors have "modules" ?

Checked the cap and rotor - connections corroded so I replaced them - still no improvement.

UPDATE!!!

Just got code P031 which is Shorted MAP Sensor Signal .

Bad MAP sensor?

bump

Ya im changing the map sensor tomorrow. The code keeps reoccuring and when its about to cut out the MIL comes on briefly then cuts out. Will provide updates.

UPDATE!!!

I have reason to believe it's the ISC motor. I come to this conclusion because when it's accelerating, there is no problem. It is not a vacuum leak because it doesn't stumble or run poorly when on. Also, it will operate fine if theres no load, ie the transaxle - if I shift it into neutral right away after accelerating, the motor stays alive.

I will replace the ISC motor and set the timing and give you guys an update. That is if you even care at all.

Would we have answered your initial question if we didnt CARE????

Please keep us updated :)

yah , its not i dont care its just i havent come across the problem yet , if i knew something id for sure tell ya

tho i did get the "fuel very low" message today on startup , it then went back up to 8 gallons after 1 mile , scary nonetheless

Would we have answered your initial question if we didnt CARE????

Please keep us updated :)

Agreed. I owe you guys an aplolgy. I am definately grateful for all your contributions and support! It is helping me to solve this quandary of sorts and I appreciate all the feedback! Please forgive me!!! :crying:

WTF!!! It just decided to resserect itself this morning!!! I go to start it to move it down the driveway, and roars to life! I was like 'This isnt right' and sure enough I took it out and it didn't stall!!! Does this have anything to do with the battery being disconnected? I assume this is how long it takes to relearn the idle data as this engine does not have an idle learn procedure?

Well..... I must say you lucked out...... Just like on the Qs, many electrical gremlins can be fixed by unplugging the battery for a while!!! Im glad you got it fixed, and I hope it stays that way!!!

It does kinda make sense, and personally I unplug the battery every so often to sort of give it a "fresh start"..... no pun intended in your case!!! :histeric: :histeric:

So how is your car running now? does it idle ok? How good does it run just above an idle? can you hear or feel it miss at all? did you Manually CLEAR Your codes and then Recheck them?

i think you should still fix the map sensor, i have a feeling that it might have somthing to do with the stalling problem. My friends Probe had a bad map and his car stalled like crazy, course the ford part didnt help :D

So how is your car running now? does it idle ok? How good does it run just above an idle? can you hear or feel it miss at all? did you Manually CLEAR Your codes and then Recheck them?
I did manually clear codes, they don't reappear, and she works great....

until this morning when I decided to change the spark plugs.

I gapped them properly and all that, tightened then to the best of my knowledge, but when I go out it rumbles at certain RPM ranges. Does this mean that I forgot to seat a wire? Is this the symptom of a dead cylinder, or is it more?

What "Brand" spark plugs did you replace the old ones with? AC DELCO? What did you gap them at? When was the last time the Plug Wires were replaced? Also Re-check your spark plugs to make sure they are seated well > but what ever you do Don't Over tighten them. Did you replace your Distributor cap and Rotor?

Unfortunately, your engine (and ALL Caddy motors since the HT4100) are VERY touchy when it comes to the ignition secondary system. This why back in the mid 80's I started changing my methodology when it comes to tune-ups and ignition systems. On the Caddy engines, I replace plugs AND WIRES at the same time. Yes, I know that mkes the job a lot more expensive but it also makes it a lot more thorough and virtually eliminates situations like this. The biggest problem is the wires. They are SO easy to damage just when removing them to do plugs, that you will damage them without even knowing you did.

My car came factory with platnium tiped plugs that are supposed to last 100k miles.... I have 80k on my car right now....

....Anyway, I am wondering, the manual says only to use AC Delco (like for everything with the car) but I wanted to get Bosch +4 platnium, becuase I heard they are very good.......and it would be a good idea to change the wires when it is time for the plugs too? Also, do high performance spark plug wires make a differnce? The 4.9 has no after market at all, and I was thinking the real good plugs and high performance wires may improve performance a little....... what do you guys recomend for plugs and wires if I want to get better performance come replacement time?

MSD wires are good.
But i dont think, that those Bosh +4 spark plugs are so great - IMO its marketing trick - better spark, lasts longer bla bla blah. But its sure - they costs more :lol

What "Brand" spark plugs did you replace the old ones with? AC DELCO? What did you gap them at? When was the last time the Plug Wires were replaced? Also Re-check your spark plugs to make sure they are seated well > but what ever you do Don't Over tighten them. Did you replace your Distributor cap and Rotor?

I replaced the plugs with NGK G-Power Platinum plugs and I also replaced the wires with Niehoff premium wires. I also put dielectric grease in the ends and seated them all properly.

I still have the same problem.

One of the plugs is bad I know it. I gapped them all at .060 as per the VECI label.

I just bought a new set of spark plugs for my 4100 > I alway's buy the A/C Delco plugs > they seem to work the best, it's been 3 years since i have changed them so they are well over due. I replaced the plug wires with 8mm type with the Heavy Duty Boots that go over the plug. I am in Complete agreement with Katshot on replacing the Wires with the plugs> I am pretty sure that i had to change the "Coil" on top of the distributor cap 3 years ago as well. I removed my Cap today and cleaned the terminals inside of it > They had carbon deposits on them so i will have to replace the cap and rotor B-4 Winter! 2dfx I would replace the NGK plugs with whatever the car came Factory with> just my opinion.

I just bought a new set of spark plugs for my 4100 > I alway's buy the A/C Delco plugs > they seem to work the best, it's been 3 years since i have changed them so they are well over due. I replaced the plug wires with 8mm type with the Heavy Duty Boots that go over the plug. I am in Complete agreement with Katshot on replacing the Wires with the plugs> I am pretty sure that i had to change the "Coil" on top of the distributor cap 3 years ago as well. I removed my Cap today and cleaned the terminals inside of it > They had carbon deposits on them so i will have to replace the cap and rotor B-4 Winter! 2dfx I would replace the NGK plugs with whatever the car came Factory with> just my opinion.

Well I took it to the dealership today - they're gonna put it on the scope and check the ignition timing. They think it's a dead cylinder and they did recommend to use nothing but ACDelco plugs in it.

We shall see!

2DFX > Whats the status on your engine? what did the Dealer say after it was put on the scope? Does it run good now?

Any updates on this. I know its been a while since this happened, but Im trying everything.

Blaze

I hate to bring this up, but are you sure you got the order right? I had a landlord who had problems after a spark plug change for no apparent reason and he swore he changed them right. We finally got out the book and counted and surprise! a switch.

No matter the cause, I think a compression loss is responsible for these stalls in older cars. You could just keep tightening the idle bolt on pre 1985 cars.

Just because you don't hear a vacuum leak from the tubes, doesn't mean the engine itself isn't leaking. I noticed my 4.5 hisses for a minute after it is shut off. this is vacuum escpaing from the engine iteself. That might not be a good thing, but it is a sign that the engine is maintaining compression when it runs. I used the maintenance size Bars Leak and it smoothed the ride considerably. I am considering doing the same thing for the crankcase since there is a slight oil smell. I just paid to steam clean it and have to try and find the source. 1 mechanic said no leaks, 1 crankcase seal, (1100$), 1 valve cover (most popular internet reason).

Does your engine smell or burn oil/fluids? What temp does it run at?
These will give people a better idea how desperate your engine is.


I have listed below my efforts to seal up my cadillac. I hope it helps you. I am interested in your car's symptoms and if trying to plug any leaks as I did will help. Maybe someone can help me. I am not done yet...


I "found" a truck/car repair center in Laurel Md. that got rid of all my 1990 Eldorado's computer codes (after I unplugged battery for 1/2 hr 1st). It broke down on I-95 due to a ground strap from the distributor. When I bought it, the car smelled, the dashboard went blank and it got 13 mpg. After my local mechanic was done, it went to 17 but then emission light came on. When done in Laurel, it got 20.5 mpg on the way home. So despite a persistent, albeit, much decreased, slight oil smell, the engine itself is running near optimal condition and has incredible pick up.


I also have a question for the more experienced with caddy's. Should the dashboard always remain constant or does it brighten periodically, to wake you up?

I believe I have found my oil leak. Hopefully you will also be able to seal up your engine and return the lost performance.

The crankcase cover did show fresh oil after last week's steam cleaning. I was also able to follow this flow down to the oil pan cover, which was soaked again. There was a spot of caked on oil that didn't come off in the steam cleaning and I removed it. Back to the top. The largest bolt, closest to the leak, (15mm) was very loose. I realize they should be toruqued to a certain level but I didn't have a wrench so I tested the ones that were still tight and gave it a guess. Tight has to be better than loose and leaking.

I was not able to smell any more oil or oil burning, but after the steam cleaning I was only able to detect the smell downhills at some stops. If I get any more wet oil on the motor I will report back but I am pretty confident now.


I would be very interested to know if your deville has any of these leakiness problems and if so, did the sealants/bolt tightenings I have used help you?
I could use some comments on the air conditioner. The car sat about 10 months at an auction house so that could explain many things. The 1st time the air conditioner came on it was because the inside got too hot for the 70 something "heater" setting. It was accompanied by an "add collant" light. I figured it had a slow leak, so would add some. No one in NY near me had a can of the old stuff to top it off, so I bought the kit to convert.

Then I went to turn it on to get a guess at how much was in the system and the air came on cold with no warning light! At least I know there is not a major leak, or the system would be empty.

The car now has no outward problems and runs great. It passed inspection easily with an emission EO49 light up. It does, however, not want to run wide open throttle when in park. The only codes I have left are a distrubutor that the shop couldn't clear ( was the ground strap they said) and the oxygen sensors open slow. They advised a cleaner instead of replacement, and I have a new filter but haven't put it on yet.

I don't want to push why it sputters at mid pedal without changing the filter as I am afraid that might strain the pump and it is too expensive to change.

When in gear, repeating the pedal push gets s smooth acceleration and the car can gain 20 mph in a few car lengths. The engine power to body size of this eldorado is like a dragster.

My intiial idea was to get a reliable older model luxury car for 2500:

Total cost:

1000.00 1990 Ebay eldorado
75.00 tip because the guy claimed be paid 1150 (split diff)
175 tune up, spark plugs/wires/pcv/air filter, analysis
160.00 registration/plates
30.00 radiator flush-(anti-freeze Bars leak maintanence version)
230.00 Breakdown costs (50 cab, 80 train, 100 rental back)
600.00 (2 new goodyear infinity, diagnose ground strap (135) clear all comp codes,
test diverter valve, steam clean engine
20.00 fancy socket lug wrench w/ light (no one should have to change a tire with those little things provided)
30.00 oil change, dura lube additive, oil filter
10.00 gas filter
80.00 Unbreakable autolock (fixes break pedal to the floor, much better than theclub or other brake devices)
total 2410.00


MPG on trip home 13.8 mpg MPG after local mechanic 17, mpg after service center 20.5

Of course the failure to WOT could be a complicated issue with the fuel injectors etc and I could have simply bought a lemon. Thanks to the advice here, I think my cadillac repeated a syndrome that has landed many in the junk yard. The fact the car had a set of goodyear Regattas in good shape says the prior owner wass not afraid to spend money on the car. The blue paint started to show the primer and the esteem of the car is lowered. Then the radiator fluid is ignored because it looks fine to the normal person. The avg buyer's car runs hot, shakes more at stops and some bolts come loose; the leakiness becomes chronic. When the car is taken to a mechanic for the smells and smoking, the mechanic points to any available part that is crying and says 2-3000 dollars and we can fix that.

The transmission fluid was dripping out a loose pan, the oil was coiming out a loose crankcase seal and the radiator had no additive in it to help keep things from vaporizing everywhere.

Time will tell, but I think I caught this motor before it was due for the crusher. IMO. 138.000 should me a mid way point for a good cadillac. Am I being foolish to think I got a good deal on a touring coupe? The blue book is only 1700 but then any car should have a few 100 in maintnance and letting a mechanic go over it.