ok, up untill a few days ago my 91 bronco hasnt skipped a beat since i got it. now i am having a problem when driving, and when idling. when i start it, or sometimes at stoplights, the RPMs will drop, or it will completely stall out, like it was running out of gas, and when i drive, it will lose power for a half a second and buck a little, and then just keep goin. the problem is very intermitant, and SEEMS to do it more when its cold.

now it sounds like it running out of fuel, and when i pulled the codes, among others, i got 556(fuel pump relay, primary circut fault) so i replaced the relay, and it seemed to behave for a bit, then today it started doin the same thing.

it dosent lose power under WOT, so that rules out the fuel filter. im kinda hitting a brick wall here. i dont know where else to check, so any and all help is appreciated.....

Jason

 

This is going to be a tuff one. I hate intermitant. When is the last time you gave it a complete new tune up? When you changed the fuel pump relay did you pull the codes again? and has it cleared that code? When is the last time you have changed the fuel filter. This is cheap and all ways good...if you don't burn your house down.

Hope someone else can help, but the hardest part is that their is probably a hundread things that could cause those simptoms.

 

i did a tune up when i bought it a year ago. i have the new fuel filter......but its kinda cold and icy in my driveway, so its not gonna happen till its above 30degrees. i havent pulled the codes since i replaced the relay.....so im in the dark
ill take a look tomarrow, pull the codes, and check a few ideas i have.....ill keep y'all posted