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Join Date: Mar 2000
Location: Lacey, WA. USA
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Quote:
Originally Posted by masraum View Post
There are two main causes for backfire. The first is an exhaust leak. The second is unburned fuel off throttle.

The unburnt fuel should be taken care of in an '85 because the ECU should kill fuel into the cyl off throttle. Unless you keep your foot partially on the throttle or you have a leaky injector, this shouldn't be the problem.
Exhaust leak is the usual culprit. However....this generally causes simple popping, not big explosions. In the olden days, we would sometimes turn the ignition off for a moment while coasting down a hill in gear. When we turned the ignition back on, there was a nice BANG.
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Old 10-31-2008, 08:36 AM
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