Help! Fleetwood FWD Fuel injector problems!

FLEETWOOD60

MEMBER
CADILLAC DEVILLE

I am in dying need of anyone who has ideas on the following: I bought a 1991 Cadillac Fleetwood Sixty Special 4.9L (same thing as deville) about 8 months ago and since day one this car has always ran a little rough at idle so at first I got a tune up plugs, wires, oil, fuel filter throttle body cleaned, distributor cap things like that rough idle still there. A month later the car started running really bad and I ended up having to replace a fuel injector then about two months later I had to have two more fuel injectors replaced, after that the car ran like it was brand new for about a month then right on time a month or so later rough idle again and what feels like a miss when driving 25 to 45 MPH going faster then 45 still there but not bad at all but the strange thing is when accelerating there is no miss at all until now. Now after two months it feels like another fuel injector has gone (engine miss all the time now). After the second and third fuel injectors went I was told by my tech that there very well might be something in my gas tank that’s causing all these fuel injectors to fail. I had a 1990 Eldorado before this car and that had the 4.5L and I never had any of the same problems twice plus that car always had a smooth idle and never fuel problems and with that car I got WAWA premium gas but was later told that there gas is not that good for these cars. I always put Sunoco 93 premium fuel in my Fleetwood so it can’t be the gas I use. I was also told to put fuel injector cleaner in at every fill up plus I was also told to never let the gas level go below half a tank by my tech in case there was something in the tank. I will drop the gas tank and replace it if I must however I wonted to see if there was anything else that could cause this type of problem like a fuel injector pressure regulator? (That’s a guess) Can adding to much fuel injector cleaner and/or gas treatment cause this problem also? Note that there are no engine diagnostic codes. Please if anyone has any ideas

Sincerely Michael G
1991 Cadillac Fleetwood Sixty Special

5 Replies

BMRFIXIT

MECHANIC
19,053 POSTS

The label on the fuel injector that we sell tells you not to use it on every fill up
Check the tank

You don’t have to replace the tank just check if has dirt in. Clean it

Where is the fuel pump?
It’s in the tank (bottom of the tank)

I m sure a lot disagree with me
� a tank or not still sucking the gas from the bottom

Good lick
Let us know

SPONSORED LINKS

Was this

answer

helpful?

Yes

No

Monday, October 8th, 2007 AT 6:29 AM

BUZZSAW

MECHANIC
1,198 POSTS

The label on the fuel injector that we sell tells you not to use it on every fill up
Check the tank

You don’t have to replace the tank just check if has dirt in. Clean it

Where is the fuel pump?
It’s in the tank (bottom of the tank)

I m sure a lot disagree with me
� a tank or not still sucking the gas from the bottom

Good lick
Let us know[/quote:fc0ffcaf14]

cadillac injectors just go bad on 4.9 if you replace 1 you should replace them all, eventually it will take out the computer if you let it go, droping tank is a waste of time unless the fuel filter is clogged

Was this

answer

helpful?

Yes

No

-1

Monday, October 8th, 2007 AT 11:30 AM

FLEETWOOD60

MEMBER
3 POSTS

I am told that the fuel pump is in the gas tank. Just wondering why the 4.9 Cadillac fuel injectors go I have heard that before but never told why. I looked up the fuel injectors for both the 4.9L and 4.5L engines and they look the same to me. I read on this website the thing about the cars computer being damaged by this kind of thing, is there anyway to test for this and if the computer is already bad would it cause the fuel injectors to keep failing? Note that it has been a different fuel injector every time so far. Also no one has disagreed with you so far. Hope this gets to the right spot, I am not sure if I am doing this correctly.

Befor

The label on the fuel injector that we sell tells you not to use it on every fill up
Check the tank

You don’t have to replace the tank just check if has dirt in. Clean it

Where is the fuel pump?
It’s in the tank (bottom of the tank)

I m sure a lot disagree with me
� a tank or not still sucking the gas from the bottom

Good lick
Let us know[/quote:ceb77a9151]

cadillac injectors just go bad on 4.9 if you replace 1 you should replace them all, eventually it will take out the computer if you let it go, droping tank is a waste of time unless the fuel filter is clogged[/quote:ceb77a9151]

Was this

answer

helpful?

Yes

No

Friday, October 12th, 2007 AT 12:21 AM

BMRFIXIT

MECHANIC
19,053 POSTS

Is it the same injectors that keep on failing?
When you removed the bad injector did you have dirt in it?
Tip injector on a clean white paper that will help you tell if you have a dirty fuel tank
And you can have the fuel tested for water not that you have problem in that area.

As for the injectors they look alike it doesn’t mean they are the same

resistant of each injector could be different
and than it’s possible to damage the computer

Why they fail think of it like a light bulb with a bad design

Was this

answer

helpful?

Yes

No

Friday, October 12th, 2007 AT 6:07 AM

FLEETWOOD60

MEMBER
3 POSTS

First off thanks for helping! I have lost my job so I am trying to keep the repair cost of this car down! To answer your question: no it has not been the same injectors, each time it’s a different one however the most resent fuel injector could be one that has already failed. I am trying to do a little homework before I bring it back to the shop. Sorry I don’t know which number fuel injectors have gone bad. Because the computer may go bad due to the injector problem I have not been driving the car at all just to prevent this problem. Let me ask you this though what are the odds of 4 fuel injectors all going bad in 5 months time and it having nothing to do with the gas tank and maybe fuel pump being at fault, also what are the odds that all 8 fuel injectors would go bad lets say within 6 months even if the gas tank was fine? I am guessing that if 4 have gone bad in 5 months and more go in a short amount of time wouldn’t it be a near certainty that the gas tank, fuel pump, fuel lines and anything else that gets the fuel to the engine be contaminated? Don’t get me wrong I don’t disagree with what you all have said in fact I will be sharing your ideas with the guy that told me I need to spend $3,000 to fix the problem. I am just reaching out at this point. I really do love this car, it’s in perfect exterior and interior shape and it only has 85000 miles on it however if I am told that I have no choice but to replace the entire fuel system then I am going to have to sell it due to losing my job. I hope I am not driving all of you crazy I just love my car when these cars run correctly there is no better car to drive as I see it after all they are like sitting in your living room and feel like your riding on air. Again thanks for all of your input so far it has been very helpful!