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The 5.0 in my crawler started backfiring, running rough, and very little power the other day after I pulled it out of the garage after working on the rear suspension. I couldn't get it to idle up without it either backfiring or stalling out. When I first cranked it cold it was fine - even power braked it (not enough to spin the tires but enough to put a load on it).
I let it cool and it cranked and ran fine again.
Cranked it again tonight after work and it's still good.
I did leave the battery off of it for a couple weeks while I was welding on it and I know the computer has a learning curve, but I am starting to think this is more heat related.
Where do I start looking? It has not thrown any codes. I could not tell you my timing and have no reference with the explorer serp on it. We timed it by ear when we first started it and I haven't had issues with it before.
'74 Grocery Getter, '73 Project Buggy, '77 Parts Rig
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double check every single plug and connector...make sure the computer is connected. good ground?
can you post a video of it running? i weld all the time on my rig with everything still connected and plugged in. do you have a check engine light hooked up?
77 built 306,Trickflow Cam/Alum Heads/dome pistons/10:1comp,nv3550,duff long arms,3.5" lift,family cage,protofab rear bumper,twin sticked, and 35KM2'sG.D.I.
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I will double ck all of my electrical connections.
My grounds should be good - I've been down that road with this motor already but it still wouldn't hurt to add another ground or two to be safe.
I will see if I can do a vid. Yes, the ck engine light is working. It lights up when the key is turned and cuts off when it starts.
'74 Grocery Getter, '73 Project Buggy, '77 Parts Rig
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where is your engine temp sensor located? is it full of water? any sensors that aren't hooked up?
it would be a good idea to check timing. the stock explorer balancer does have timing marks on it. i timed mine without issue.
mine started acting up when it gets warm as well. hadn't checked into why yet.
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Are you running KOEO and KOER codes?
Is this an exhaust or intake backfire?
Timing or vac would be my first stop after a KOER test.
'77 351w- Explorer EFI, 4R70W, 4-link, lockers, 4.56, 35" MT/Rs with a severe rock addiction.mokin:
Roads? Where we're going, we don't need roads.
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I'd check the coil and ignition since it seems to be heat sensitive.
'72 TBA...
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I agree with bucket. The coil is a classic offender when it comes to heat sensitive issues.
'77 351w- Explorer EFI, 4R70W, 4-link, lockers, 4.56, 35" MT/Rs with a severe rock addiction.mokin:
Roads? Where we're going, we don't need roads.