86 F150 with EFI, bad mileage and a few other symptoms
#1
86 F150 with EFI, bad mileage and a few other symptoms
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!
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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