86 Bronco II Backfires while Accelerating

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Sep 25, 2013 | 02:51 PM

redsquirrel_7

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86 Bronco II Backfires while Accelerating

Hello everyone! I took my 86 Bronco II (2.9L V6) on some fun trails last night, and when I got back on the pavement, it started backfiring while accelerating. It is also running rich (black smoke out the tailpipe). Does anyone have any suggestions? I have checked the FPR, and distributor (might have come loose), but they both seem ok.

Sep 26, 2013 | 08:10 PM

f5fordgirl

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Did you check the air filter?

Sep 29, 2013 | 04:25 PM

redsquirrel_7

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Yes. I have a reusable airfilter and it is clean. I have also replaced spark plugs which didn't help. Is there some sort of sensor that could cause this if it died?

Oct 2, 2013 | 05:41 AM

mebe2k

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From: Ford, WA

have you checked the MAP sensor? maybe the vacuum hose came off/broke, electrical connector loose or the sensor is bad..

Oct 15, 2013 | 08:26 PM

redsquirrel_7

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The MAP sensor seems to be fine. (Tested by unplugging it and running the engine.) The EVR is making a strange whining noise after you shut off the engine though. Could this be the cause? Thank you for the response by the way.