How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Randall C Your Own Question
Randall C
Randall C, ASE Master Tech
Category: Cadillac
Satisfied Customers: 12803
Experience:  ASE Master Tech, 32 years exp,Cadillac 6 yrs
Type Your Cadillac Question Here...
Randall C is online now
A new question is answered every 9 seconds

1990 Cadillac: Engine runs jump..dead stop

This answer was rated:

1990 Cadillac Sedan Deville - Engine runs rough at start up, wants to die out. After warm up, will run and accelerate fine, strong engine. Will want to die out if you jump into passing gear or from a dead stop. Also will give a small backfire on occasion while driving - no reason. What do I look for?

Tracer :

Hello, My name I Randall. I will do my best to assist you with your question.

Tracer :

Can you tell me if the slight backfire you hear comes form the exhaust/tailpipe or from under hood at engine?


under the hood

thanks checking some things. back shortly
Ok, a backfire through engine is from a lean condition. all your symptoms tend to point to fuel delivery problem.This engine had a problem with the fuel pressure regulator. They changed the design slighty. Fuel pressure is controlled by the regulator mounted on fuel rail. I suspect it is fialing but cant be 100% with overnight fuel pressure reading and fuel pressure reading when problem happens. I lean to a bad regualtor at this point
Randall C and 2 other Cadillac Specialists are ready to help you