1985 Cadillac EL Dorado Won't start/Fuel pressure problem.

JOE DD

MEMBER
1985 CADILLAC ELDORADO

Engine Performance problem
1985 Cadillac El Dorado V8 Front Wheel Drive Automatic

I have a 1985 Cadillac Eldorado that wont start unless I spray starting fluid into the Throttle body.
I rented a fuel pressure gauge and it showed no pressure at all on the fitting at the line at the TBI.
When I turn on the key, fuel pump does run for a couple secs. Disconnected the fuel filter and checked pressure there as well, none.I cranked it with the line removed at the filter and fuel does pump out but not like I think it should, not very forceful.
Would this be a weak pump or a faulty pressure regulator.I have heard that these are known for ruptured diaphrams in the regulators. Help, I dont want to drop the tank and put in a pump only to find out im wrong. Dont have the money to waste. Any advise would be welcome.
TIA

8 Replies

RASMATAZ

MECHANIC
75,992 POSTS

To rule out the fuel pump you must check the fuel pressure if its within specs

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Thursday, October 28th, 2010 AT 5:06 AM

JOE DD

MEMBER
14 POSTS

I DID check fuel pressure both at the fitting at the throttle body and before the filter, both show no pressure at all. NONE.
But with the car jacked up and the fuel line off before the filter or even after the filter, fuel does pump out, albeit not real forceful. Not sure if its just because the car is jacked up or what. Pump does run, but fuel isnt really coming out forceful at all. If I disconnect line at TBI and crank it, no fuel reaches there at all.I'msuming its a weak pump but not sure if it can be the pressure regulator.
Any additional advise would be appreciated.
TIA