missing, backfireing and dieing, 351w

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Jul 21, 2004 | 01:20 AM

skelator

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From: West Texas

missing, backfireing and dieing, 351w

i have an 84 bronco xlt with a 351w. it has been missing very bad it backfires out of the carb and tail pipe, it idles just fine, but when i am driving and i hit a bump of anykind it makes it worse, also when it starts doing this the tack starts bouncing wildly. what is wrong?

Jul 21, 2004 | 04:33 AM

Pro-Street/StateTK

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From: East Flat Rock NC

First thing when starting to read this i thought ( timing chain ) ,but hitting
the bump making it do it more sounds like a short or a lose wire. I have heard
of a timing chain being so badly worn that hitting a bump could cause it to
jump a tooth or two ,but the idle would be changed. So I think lose wire or a
short.

Last edited by Pro-Street/StateTK; Jul 21, 2004 at 04:40 AM.

Jul 21, 2004 | 05:43 PM

skelator

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From: West Texas

all the wireing in this sucker is screwed, i have pulled alot of it apart and taped it back together, i even replaced the harness connected to the tfi module. so far i have replaced these parts; coil, cap, rotor, plugs, wires, ignition control module, carb, fuel filter, fuel pump, parts of wiring harness, and there are no vaccum lines connected exept for the pcv

Jul 21, 2004 | 09:31 PM

Pro-Street/StateTK

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From: East Flat Rock NC

Have you checked the engine to firewall ground for titeness and clean the metal.

Jul 21, 2004 | 09:36 PM

skelator

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From: West Texas

kinda hard to see back there but i will check, any suggestions on how to repair bad wiring?

Last edited by skelator; Jul 21, 2004 at 09:51 PM. Reason: needs to be longer

Jul 22, 2004 | 11:52 AM

Kemicalburns

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From: Bend,OR

i would replace the whole harness with a complete one from a wrecking yard. i think you can use one up to 85-early 86 thats pre efi. fixing with tape is not a good way , you should use crimps and connectors. get a haynes manual it should have a wiring diagram inside . if not do a search on google

late

Jul 23, 2004 | 12:49 AM

skelator

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From: West Texas

hey guess what, when i put the new carb on i forgot to adjust it properly, so i did and it ran great all day, i will keep you posted and see if that fixed it.