Mechanics

CADILLAC EL DORADO FUEL PRESSURE PROBLEM

1998 Cadillac El Dorado • 80,350 miles

My car surges after it warms up mainly, It started doing this a few weeks ago.I changed the fuel filter, fuel reg. Then the spark plugs and wires. And none of this helped. I put treatment in the gas, thinking I may have water in it. But it is still the same. Thanks for any help.
allenflucas@aol. Com
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Allenflucas
January 9, 2013.



Scan for codes and check fuel pressure first. Then clean throttle plate with choke cleaner on both sides

Hmac300
Jan 9, 2013.
Ok. Checked codes P0175, I put pressure gauge on it. And found out after it warms up pressure jumps from 75 psi down to 40 psi. And sounds like it misses when it dose that. Thanks for your help

Tiny
Allenflucas
Jan 10, 2013.
P0175 means you could have a leaking injectors on one bank or a bad O2 sensor. But check for a collapsed air duct leading to throttle body as it could cause the same thing. Also fuel pressure should be 48-55 psi key on engine off. It should hold pressure within 5 lbs for 5 minutes if not it could be a regulator but if going below to 40 sounds like a clogged filter or pump. Fuel pressure can be taken at any temp and should be same. If you have a or suspect a leaking injector havea pro scan this as he can do more than yours assuming that this is an auto parts store scanner.

Hmac300
Jan 10, 2013.