I have a 94 dodge ram 1500 4x2 with a 3.9l engine in it. it has 119000 miles on it. today i was driving it and it started to lose power and slow down. the truck also started shaking. i could hear lifters bottoming out to, like there was no oil. with how much loss of power there was, it almost acted like the engine was seizing up. this started under normal conditions. i then had a hill to go up. i climbed the hill slowly and carefully, listening to my truck. in 4th gear, any rpm, as i get on the gas, my truck would start making the noise of lifters bottoming out, shaking, and losing power. so i shifted down to 3rd, and in 3rd gear at higher rpms, as i got on the gas, it would again start making the noise, shaking, and losing power. i got to the top of the hill, and put oil in it, thinking just in case that it maybe i was out or low of oil and i wasnt getting any. (my truck has bad valve seals, and burns a little oil, not a major problem 2 me) i went down the otherside of the hill, and got to the bottom, and it still was making the noise and losing power. i didnt seem to notice this problem happening in any other gear, and this has never happened before. im not sure whats goin on. i also have a big missing problem that occurs when my tank is at half and below. i believe that this problem could be that some hose in the tank on the sending unit is cracked and as it gets below half a tank, and no gas covers that hose, that it sucks air in with the gas, making my truck miss. would that be a good assumption? Please help me out. it is an older truck, but id at least like to keep it running until this spring/summer when i can get a new one. any help is greatly appreciated.

 

Sounds like plenum and cat problem. Check the fuel pressure too. If the oil pressure gauge was reading good, then I think what you were hearing was a ping not the lifters tapping.

 

ok. we did just replace the intake gasket and plenum gasket this summer. and the plenum gasket was blown when we replaced it. and the oil gauge was fine when i heard the noise. it was a kind of tapping i was hearing. but a ping would fit the description to. what would the ping be from?

 

It could be an exhaust leak at the manifold. But you should try dumping a ton of Techron + in it or do the seafoam thing and see if it clears up. Since the gasket was bad , you probably have a ton of carbon built up on the valves and/or plugs. And like I said, check the fuel pressure.

 

ya. that would b a good idea. ill check the fuel pressure on it and see how it is. then run some of the techron + through it and see how it runs. that sounds like a good place to start. ill keep posting on what all happens. thanks. i really appreciate your help.

 

Please do keep us informed. And get the cat checked.

 

will do. thanks alot.

 

im going to be checking my fuel pressure tomorrow at work. what should it be around? rite about 49lbs?

 

+1 cat

 

ive had a simmilar problem when i get low on gas. soon as i fill up it goes away. My gas gauge doenst work so i have to fill up every 200 miles. So id make sence if it were a fuel problem. Im interested to see what you find