Hey guys,
When the tank is full, I have no problems, but as soon as I get to about half tank on my 99 5.9L 2500 and have driven for about 1-2 miles straight at about 45mphs+, and then come to a stop light, it will drive real weak, like it is either not getting enough air or fuel. I slip it into nuetral or park, no problems, it revs up and sounds perfect, put it back in gear, and I better be putting the gas down or I am risking dieing out. Gas pump is about two years old, but I was filling up a gas station notorious for poor quality tank, which I have now stopped buying from. And I took apart and recleaned IAC a few months ago which showed immediate improval from the idleing problem I was having before. It almost seems like the throttle body is sticking both down and up at times. I sprayed it down real good when I cleaned the IAC. Any ideas would be appreciated.
Thanks,
Kevin

 

Fuel pump sounds like it's bad, but it could be both. How does the bottom of your intake manifold look? Dirty? Oily?

 

If it is oily or dirty what does that mean ??? im havein a prob kind of like that in my 99 durango 5.2 v8 but mine runs fine when cold but when it warms up it runs like crap ... and my gas gauge likes to bounce around too idk whats wrong with it i have replaced the iac,map, o2 sensors ... i cleanded out my tb and it was pretty dirty .. does that mean the gasket between tb and intake is bad ???

 

If you open the butterfly valves on your intake and see oil it usually means your plenum gasket is blown, or your PCV Valve is bad. Replace the valve since it's nice and cheap. Then I'd check your plenum gasket.

 

i'd put in some gas treatment that claims to eliminate water from the gas. most all of them do.

dammit - i answered a thread from April 2010. **** me running.