Hello,

I'm new around here, and I've only had my truck for a couple of months. It's an 86 F150 Lariat auto 4x4 with a 302 V8. I've got a few symptoms, and I'm thinking they're all related, so I hope someone can point me in the right direction.

Firstly, I'm getting really terrible mileage. Under 10mpg, definitely running rich. Also, the engine does a little bit of "chugging" at certain rpms. Usually lower rpms in first gear. Once I give it gas or it hits into 2nd it usually stops. Last, it sometimes dies when going from drive to reverse.

I thought it might be something with too much gas being pushed in, so I checked the fuel pressure. Key in and engine off, its at 40psi which I believe is good, but when I turn the engine one and idle it drop to 30 which I think is low. And then it barely changed when stepping on the gas. Not sure if I'm leaking somewhere but I'm not certain what common problems that this could indicate.

A couple of other notes: I recently changed the ignition module. And I know that the tank selector valve isn't functioning correctly, I found that out when I ran out of gas because it was still pulling from the front tank after I switched to the rear. Also I didn't notice the "chugging" symptom until after I had run out of gas the one time, but that could be coincidence.

Hopefully someone can give me some direction on where to look next. Thanks for any help!

 

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