comptz

My mechanical oil pressure guage that is hooked into the top of the oil filter adapter and i am gettin around 60 psi. it will leave a small puddle under the tube if it sits for a few days in my neighbors garage whan im working on it.

wannadiesel

I believe your engine is sound. You need to look at the simple things that cause low power before you tear a perfectly good engine apart. I know of several strong running trucks with over 300k on the original engines.

comptz

ok, I have around 600,000 on mine. What could be causing this low power? It seems that i have to stomp it to speed up over 60mph.

wannadiesel

Check the throttle travel first. Does the throttle lever hit the high speed stop when the accelerator is floored?

This is an automatic trans truck?

Crossy's son

600,000 miles? wow well your valves are supposed to be checked and adjusted every 47,000 miles according to the manual. but whatever. lol not that important

If its the original fuel lift pump then you may wanna replace it FOR SURE. (do it) Umm, your injectors maybe getting clogged up that could cause a loss in power. It has to have something to do with your fuel system.....

comptz

Yes, this is an automatic. I dont believe that it hits the high idle speed stop, it seems that it hits the t.v. cable first.

comptz

Yes, i do believe that this is the stock lift pump. I know my dad has had them adjusted atleast once,(i think in 92).

comptz

What damage can happen if you dont have your valves adjusted and checked?

Alwaysworking

they would have to be really out of adjustment to cause any damage

comptz

ok, Is there a diagram on here that tells you how to adjust them or would you have a professional do it? I myself have never adjusted valves before.

Alwaysworking

in the sticky

90firstgen

Your injectors could probably use a rebuild too. Makes a big difference for cold starting, fuel atomization etc

SkinnyBTN

If I had a truck with 600,000 miles on it I would be trying my best to avoid a rebuild as long as possible. Along with trying to get some nice hp #'s out of her. Having a truck with that many miles and still running is a heck of a statement. If it were mine I would look through the sticky and do an in depth inspection/maintenance check of the truck with a few upgrades and see how she runs then.

wannadiesel

Well, there's your problem. Adjust what you have to to make it go to full throttle.

archer39

that is a problem, i would fix that then get a fuel pressure gauge. Get the gauge before you go replacing parts. You can get cheapo gauges that will work fine for diagnosing problems.