My trucks acting all funny.

[numenorian101]

So I've been getting really poor gas mileage, my gauge is busted and whenever fuel gets low, the truck starts to shake violently. It used to be when there was about 10 gallons left, now it's acting up after only using 16, which is not quite half a tank. I think the fuel pump is going out, I've never replaced one so does anyone have any ideas or advice for an aftermarket model, replacement advice and the general procedure I need to follow? Or maybe any ideas if it's not a fuel pump? It's a 1993 Ramcharger 5.9 Magnum with a 34 gallon tank.

[crazzywolfie]

does it also start running like crap when it is shaking violently?

the hardest thing i ever found dealing with replacing the pump is rust but i don't think that should be to much of an issue where you live. i ended up cheaping out and just replacing the pump with the cheapest pump from rockauto. so far so good but you might want a new sending unit if your gauge don't work.

my best advise i can give you for removing the tank is disconnect as much as you can then drop the passenger side first and the the drivers side will just slide out. you can try using a jack to make the removal a bit smoother

[SixGun]

Sounds like the fuel pump could be the culprit but have you checked codes?  A couple of other things to consider would be the O2 sensor with poor gas mileage and drivibility.  Also, depending on codes, would be the crankshaft sensor since its magnum and the plenum.  Surprised Wolfie didn't mention that. He's usually on top of that issue.

[crazzywolfie]

lol i stopped hanging with the 2nd gen guy so much so i have kind of forgot few of the things to look at when trouble shooting. my aluminum plenum pan is still sitting in the basement waiting to be installed.

i found when my fuel pump was dying there was no codes at all in the computer but that is a good place to look first.

[SixGun]

Yeah, "if" there's no codes.

The plenum leak would cause it to run rough if I remember.  Also, can't a vacuum gauge help diagnose a plenum leak?

[crazzywolfie]

the old computers are pretty limited.

ya they say you can diagnose a leaking plenum with a vacuum gauge but i am not 100% sure.

[rjtx667]

also don't forget the fuel filter.

the last thing I can suggest is fuel injectors... 20 year old ones might work but not great. go on eBay and find some Bosch 4 hole injectors

[numenorian101]

Well I'm pretty sure it's the pump. What all can I replace while the tank is dropped to avoid doing it again? Also what is the larger canister located above the fuel pump on the outside of the tank?

[SixGun]

Are you talking about the fuel filter?

Shoot a picture of it.  Maybe rollover valve?