Had some brake issues as I reported in another thread (if others would look I would still take some advice on what is going on with it, but is fixed now for the most part.); have her up and running, but I cannot seem to get her to drive over 30 mph or tach over 2000 rpm. Ran some engine diagnostics and not anything there. Checked the fuel pump pressure and is running at about 50 psi. Thinking I might have a vacuum problem any ideas where I should start looking or of I am way off in my thinking as I often find myself doing?

 

Little off the topic here, but I bought this truck to build from my 2000 4.7l automatic dakota 4x4 SLT. The frame got bent and I just did not want to go through the hassle of having a rebuilt title and it was going to cost me around $1900 to have the frame bent back and a back glass put into it. That was not including the body work and front end work that needed to be done. It was still drivable but had a very bad pull. I was thinking of maybe doing and engine swap if I cannot get this 98 going well. But if I do get it up and running like it should where would be a good place to sell the motor and tranny. I was the only owner of the truck and took very good care of the engine it is still strong with 167,000 miles on it.

 

I could really use some advice on this one because it is driving me nuts and costing me money. I cannot work without a truck. I hate to beg, but can someone toss some ideas my way. I have a 5 speed tranny. The diagnostics are looking ok on it while it is in idle, but at the moment I am just picking at straws. Please someone help me.

 

you more than likely have a clogged catalytic converter. Here's how you can check it with a vacuum gauge: rev the engine up to 2000 RPM, the vacuum gauge for steadily drop. When there's a huge restriction in the exhaust, it severly limits the power an engine can make.

 

Check it by pulling it off

 

I agree. Just had the same issue and it was a clogged cat. I cut it out and it runs like new.
Give it a try.

 

I cut off the cat and it still is running terrible. I guess I am going to start looking through the fuel pathways. Perhaps where it set in a barn for so long something must have gotten gunk up in there somewhere.

 

Do you have an O2 sensor behind the cat?

 

If your brakes are almost nonexistent still and she runs like you say you may be missing the power brake vacuum hose with that off or missing your brakes will be crap and the engine will run like crap you may have some other vacuum lines missing or clogged or a manifold leak crack check all the emission components pull them out and inspect all the sensors and connectors.

 

Like 98dakaz says, check your brake booster. There should be a thick vacuum line from that to your intake manifold. Be sure it's connected, not cracked or clogged.