xRedGTx

My brother has a 92 F-250 That has a 351w in it. It'l idle and run but when you put it on the floor it pops and backfires. So we checked timing, here is where it gets weird, with a timing light on it retards timing when you rev it instead of advancing. It actually runs better with "the pill" out than with it in. It has new alternator, TPS, MAP, IAC, fuel filter and a freash trans rebuild. We are stumped any help is greatly appreciated.

Steve83

The more we know about it, the more we can help. Click this, read the caption, and put EVERYTHING you can find about the truck into your signature:


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Include all its current physical details, and its history. Pics will help, and there's a link in that caption to a free hosting site with instructions. When (date &/or miles) & why each part was replaced, with what brand & PN from what source. What test each original part failed, and whether the replacement passed the same test.

By "pill", do you mean "SPOUT connector" as shown in this pic?


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A Haynes manual is a wise investment, but read this caption before buying one:


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xRedGTx

Yes the spout, In the mustang world we have nicknames for certain parts. Anyway on this truck I don't know any history on it. It is 100% stock minus the replaement alternator, tps, iac, and map sensor. He said it runs fine at lower rpm but if he has to put his foot down it runs like crap pops and backfires. We checked timing last night and when you rev it it retards instead of advancing. We set the timing at 15° and took the spout out and it runs way better.

Steve83

Open the EEC:


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