Bronco running RICH
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From: Conyers
Bronco running RICH
1986 Bronco with the EFI 302. Ran good, and then I let it set for awhile. It quit running good and started running REALLY rich. Replaced the transmission, because the stock AOD was burnt up.
I get codes 12, 21, 22, 34,42 when I run the self test. 42 says system rich, 34 is the EGR valve outta range, 22 is MAP outta range, 21 is Engine Coolant Temp outta range, and 12 is Cannot control RPM during ER Self-Test high RPM check.
I ran the codes yesterday and got TPS out of range, so I replaced that and no improvement. I also replaced the O2 sensor because it had been in there from the factory. I'm going to check the MAP and ECT in a few minutes and look for shorts...Any ideas where to look from here?
I get codes 12, 21, 22, 34,42 when I run the self test. 42 says system rich, 34 is the EGR valve outta range, 22 is MAP outta range, 21 is Engine Coolant Temp outta range, and 12 is Cannot control RPM during ER Self-Test high RPM check.
I ran the codes yesterday and got TPS out of range, so I replaced that and no improvement. I also replaced the O2 sensor because it had been in there from the factory. I'm going to check the MAP and ECT in a few minutes and look for shorts...Any ideas where to look from here?
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Joined: Jan 2006
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From: McNairy county, TN.
I had a '91 f150 300ci EFI with 270,000 miles that started runing rich and throwing out all kinds of stupid codes. A buddy of mine had a spare computer for a 300, so we tried it for giggles and grins. It ran beautiful, so i got a replacement one from auto zone and sold it at 320,000 miles. Might try that before you replace anything else. It would be worth a try if you could get ahold of one to try.
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From: Coweta,GA, GO DAWGS!!!!!!
I'd try the ecm first thing if ya can find one. Had the same thing happen on my 91. Replaced all of the sensors that were related to the codes and still had the codes. Found a new ecm at gene evans and it's run great ever since.
Try and find ya one, if ya have no luck, go ahead and start that engine swap
Try and find ya one, if ya have no luck, go ahead and start that engine swap
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From: Conyers
I know this is an old thread, just letting everyone know what the cause for it was. The MAP sensor was not receiving full vacuum, therefore the computer had no idea what to do, so it just went FULL rich. Still running the SDEFI, and mass air will be later.
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From: McNairy county, TN.
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