96 Suburban hard start when cold

rjirvine · August 24, 2006

My friends 1996 Suburban is hard to start when cold. It runs fine when Hot, then turn off then start again starts fine, fuel filter is new. Any ideas? I'm thinking fuel pump?

sub5 · August 25, 2006

My friends 1996 Suburban is hard to start when cold. It runs fine when Hot, then turn off then start again starts fine, fuel filter is new. Any ideas? I'm thinking fuel pump?

<{POST_SNAPBACK}>

I had that problem last winter and we found the fuel pressure to be bordeline. Same with me once it started it was fine but got to a point where it missed while driving and also died on the highway. Usually these pumps just die on you but sometimes they fade away. This was my second time replacing the fuel pump but I put in an aftermarket High output pump this time. 10% more delivery, quiet and runs cool. And it cost me less than the original part from GM which is crap. The bad part was I have a 40 Gal. tank on my burb so I had my Mechanic friend do it for me. Check this site but you have to go through a dealer to get parts.

http://www.venom-performance.com/nf/html/c...lettruck/c2.htm

Hope this helps out.

Cheers

John

95Sierra2500 · August 25, 2006

Definately sounds like a fuel pump. Whatever you do, try to replace it when the tank ISN'T full. It's never failed though that EVERY time I've gone after a fuel pump, the tank's been full, whether it be a '90 suburban w/a 40 gallon tank, or my old '99 Jimmy (now my fiancee`'s).

rjirvine · August 25, 2006

I'll pass the fuel pump idea along to him. And yes, he did just fill his tank.

rjirvine · August 27, 2006

Well, my friend got a fuel pressure tester and his pressure is 62 PSI, the haynes manual calls for 60-66 PSI. And it's high 50's when running (max drop 10 PSI limit). It still is a bear to start when cold, and starts right up when hot.

He recently changed the fuel filter/cap/rotor/ and plugs in order to try and fix this problem. The fuel pump is less than 2 years old. I'm having him clean the MAF and the throttle plate and check for any obvious disconnected lines etc. His is SFI fuel injection. He has no codes.

Any other inputs?

sub5 · August 27, 2006

Well, my friend got a fuel pressure tester and his pressure is 62 PSI, the haynes manual calls for 60-66 PSI. And it's high 50's when running (max drop 10 PSI limit). It still is a bear to start when cold, and starts right up when hot.

He recently changed the fuel filter/cap/rotor/ and plugs in order to try and fix this problem. The fuel pump is less than 2 years old. I'm having him clean the MAF and the throttle plate and check for any obvious disconnected lines etc. His is SFI fuel injection. He has no codes.

Any other inputs?

<{POST_SNAPBACK}>

My pump went bad on me after 13 months so it doesn't mean anything that it's 2 years old. But from the pressure readings you have than I would rule it out for now. The SFI system can be a problem when they get old since the injection system is inside the intake.

95Sierra2500 · August 28, 2006

Well, my friend got a fuel pressure tester and his pressure is 62 PSI, the haynes manual calls for 60-66 PSI. And it's high 50's when running (max drop 10 PSI limit). It still is a bear to start when cold, and starts right up when hot.

He recently changed the fuel filter/cap/rotor/ and plugs in order to try and fix this problem. The fuel pump is less than 2 years old. I'm having him clean the MAF and the throttle plate and check for any obvious disconnected lines etc. His is SFI fuel injection. He has no codes.

Any other inputs?

<{POST_SNAPBACK}>

I wouldn't rule the fuel pump out, my fiancee`'s '99 Jimmy's fuel pressure before starting was 61 PSI and at times it WOULD NOT start. It also had a slight misfire from time to time. Replaced the fuel pump and all problems went away.

rjirvine · September 4, 2006

Well, my buddy and I canged his fuel pump today that had a lifetime warranty thru AutoZone (has since changed to 1 year). I made him buy some new o-rings and a bottle of techron concentrate to put in the gas tank. The truck started right up. He's gonna try it in the morning (when cold), but I thin the problem is fixed. Thanks Guys!

PS It took about 3 hours to change it on his suburban with a 40+ gallon tank and a trip to the parts store, we siphoned it down to 1/8th tank. He got a mouthfull of gas and was still burping it 3 hours later. Lol, the entertainment value was worth pissing away my labor day afternoon, even though I warned him about it!