86 Bronco Backfires

Tiny
LD
  • MEMBER
  • 1986 FORD BRONCO
I have an 86 full size bronco 302with 176, 00 miles. The timing chain and ecu have been replaced 25, 00 miles ago. When you accelerate hard it will surge and backfire thru the intake. I have changed plugs coil both fuel pumps and one fuel filter. The fuel pressure with key on engine off is 40 lbs. With key on engine running fuel pressure is 30 lbs. Any advice?
Saturday, August 18th, 2007 AT 12:48 PM

1 Reply

Tiny
2CARPRO JACK
  • MECHANIC
  • 11,533 POSTS
Does it run rough at any other time? Compression and leak down test ok? Your fuel pressureis within spec, so I think we can go past that. Been tuned up recently? (Motorcraft plugs, wires, cap, rotor)
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Wednesday, August 22nd, 2007 AT 11:51 AM

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