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5.2 magnum backfires into intake
Posted to Technical Discussion Forum on 7/23/2013 27 Replies

OK it's a mutt.

95 Jeep Wrangler

5.2 magnum out of a 94Jeep Grand cherokee

95 Dodge truck computer (standard)

ax-15 trans

The engine was rebuilt about a month ago and will start and idle fine. Driven it around the block a few times checking things. Under acceleration it will backfire in to the intake. Plenum gasket replaced, new fuel pump, map sensor, wires, cap, rotor, plugs cleaned and gaped, EGR valve working correctly, checked vacuum hoses and lines (replaced as needed) swapped the one O2 sensor it has. The wiring harness was sent of to Hot Wire Auto as to be adapted to fit the 5.2 in the wrangler. Checked: distributor, crank sensor, throttle position, air idle control valve all are within specification. I pulled the fuel rail on it to see that all the injectors are actually firing. I've been battling this thing for a month help me.

Thomas Huth
TBH Construction
Canyon Lake, Texas, USA

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