Bad Gas - and not the Rolaids kind!

cadillac
deville

#1

Well the saga with my wifes car continues. I just put in a new fuel pump, the old one was toast, and tried to start the car. I figured one or two attempts and it should fire right up. Guess again Nostradamus. It just spit and sputtered a few times and then wouldn’t even try to fire. So, I thought maybe there was an air pocket in the fuel line and I could bleed it from the line by taking the needle out of the valve on the fuel rail and cycling the pump a few times. I put a hose on the valve and let it run into a jar so I could see it from inside the car and could tell if it hit an area of air in the line. When I hit the key and the pump fired up fuel came right out of the hose into my jar as planned only it wasn’t what I had expected to see. It was very cloudy and only had a slight smell of gas to it, kind of smelled like old gas does. I kept cycling the pump until I had a nice clean flow of fuel from the hose. I figured I should hit some clean fuel soon because I had just filled the car up before all this trouble started.

I tried it again with clean fuel at the rail and it still wont start. I used some starting fluid to try and help it along and still nothing. At this point it will crank and try to run but wont for more than a second or so. Will this bad gas eventually clear itself or do I need to do something more to get it all out of the system.


#2

I forgot to mention this car is a 2000 Cadillac Deville DHS.


#3

did you have any check engine light issues before? If not, i would say possibly a crank sensor issue if the fuel pressure is good. remember, just because you got a part out of a new box doesn’t mean it is a good part. test the fuel pressure.

have you tried to keep spraying ether (starting fluid) into the throttlebody? have the wife crank the car over and spray, then when it starts to die off, spray a bit more…repeat. if the car will keep running like this, fuel is still an issue, if not, start looking into sensor issues.


#4

No on the check engine light, it never ran a code. I suppose this could be a sensor issue but I’m fairly sure it is fuel related due to the bad gas I discovered. My main question is will this gas clear itself from the injectors if I keep trying the starting fluid to keep the engine running or do I need to remove the injectors and clean them by hand? Another thing about the fuel rails on this engine is the valve that I bled the gas from is located between the rails instead of before or after the rails. So that means that 4 of the injectors should have fresh fuel while the others will have to use the old fuel before new gas will be introduced. How long should it take for new fuel to cycle through the injectors on that bank of the engine and will I hurt anything if I keep on doing the starting fluid routine.


#5

" I figured I should hit some clean fuel soon because I had just filled the car up before all this trouble started."

How did you change the fuel pump with the fuel tank full??


#6

staring fluid shouldn’t hurt anything. may also want to put in some injector cleaner in the gas once you get it running. lucas makes some pretty decent stuff…or just take it to a shop and have them do an injection system treatment. not terribly expensive and most reputable shops have the proper equipment to do it right.

also, if you took the lines off, you may still have air trapped in the fuel system which can be a real pain in the arse to expell. i would suggest keep trying the starter fluid trick. it should clear up within a couple of minutes.


#7

One positive thing about all this is the tank on this car does not need to be dropped from the car. There is an access plate in the trunk that allows you to do the fuel pump change from there.


#8

I didn’t remove the lines just took the needle out of the valve on the fuel line and ran the pump until new clean fuel came out and then put the needle back in.


#9

UPDATE:
I got the car running today only after replacing the plugs, they were completely fouled from the bad gas. The car has a slight roughness to it’s idle so I’m going to run some injector cleaner through it and see if it helps. Also, the check engine light is on now but I’m going to drive it a while and then disconnect the battery and see if it will clear. I never knew that some bad gas could cause so many problems with a cars fuel system.


#10

There’s no need to disconnect the battery. If the problem is resolved, then the light will go off by itself after enough driving.