I am getting only 3.6mpg on the street and 5.0mpg on the freeways. the check engine light came on and the truck was have problems starting all the time it takes about 3 turns before it starts. but once started it runs ok. sounds great but eats up all the gas. has little power. so i did a tune up on it changed the plugs, wires, distributer cap and rotor. no changes so i took it to the machanic and he checked it out said it might be the injectors so he wanted to switch the 3 and 6 with to different ones to see if the same codes come up. i was having miss fires on the 3 and 6 cylendors but no changes happened. i drove about 80 miles the light came back on i took it back to him he said now it was running lean..? no other codes! what should i do. he charges me to switch things around not fix it. and he said he is not shure what is wrong with it but i cant aford to keep taking it to him. i need it fixed. PLEASE HELP!!! any suggestions????

 

Welcome to DF.

First, before anything else, please read this:
https://dodgeforum.com/forum/dodge-ra...s-section.html

I will move this to the 2nd gen section for ya. Exactly what trouble codes does it all come up with?

 

OK. So here are some things that will help you.

1. Put your vehicle infoe, such as year, model, 2wd or 4x4, auto or man trans, etc in your dignature so that everyone looking at your posts will have an idea about what your vehicle is.

2. Search the DIY section for the plenum fix thread, and check to see if your plenum gasket is bad. Relay this information in your nex tost.

3. Also, as HeyYou asked, list the trouble codes you are getting.

This will help and we all won't repeatedly ask the same questions, and we will be better able to help.

 

3.6 mpg and your mechanic says it's running lean?

Either there's a thumb-sized hole in your gas tank, or you need a new mechanic.

On a less wise-guy note:

It doesn't sound like the injectors, because I think they'd all have to screw up at the same time to cause MPG like that. Maybe the PCM is fried, and is firing them all continuously(?). Does your exhaust smell of unburned fuel? Getting any backfires from the exhaust system?

Have you ruled out the most obvious things, like a loose fitting somewhere on the fuel line or fuel rails?

This will be interesting; never heard of fuel consumption that bad.

 

Sounds like you're driving a ram are your breaks hot after you drive for a little bit? They could be always engaging which would also bring down your power and mpg.

 

plenum gasket is a big cause of your problem. mainly all of it. and your leakin gas somwere on that truck. check all your fuel lines.. **** drop the tank and work your way up

 

Switch from putting corn oil in the gas tank to putting gas in it?

 

its a 99 dodge ram 318 5.2l slt lariame 2 wheel drive automatic. sometimes in the morning it does smeel like gas.no holes in the gas tank and no sighn of leaking fuel. but this is my only truck no other car so it sucks to be me right now. the brakes are not hot but my break light is on and my abs light also because of the abs sensor being messed up on it. the trouble codes on it before the machanice earased them were p0306 p0303 p0301 he said some times p0304 also but not all the time. now only running lean code comes up not sure what code that was he did not tell me.the machanic also said it might be the computer but he said he needs to check other things first. how can i tell if it is the computer? were is the plenum gasket at?

 

the pcm thinks its running lean because it is getting incorrect information from the maf or o2 sensor, it isnt actually running lean. because the pcm thinks it is running lean, it dumps ALOT of extra fuel in order to correct the "lean" issue.

either your maf is bad or your o2 sensor is bad. my bet is on the o2 sensor. unplug the precat o2 sensor and see if it improves.

 

3.6 ? How are you calculating the mileage? And pull the oil dipstick and see if it smells like gas and is at the correct level.