Originally Posted by Maxont
Im sure this has been posted a million times here but im posting this at work and did not have much time to read through the posts... here goes
I just recently baught a 99 7.3, On cold startups the Engine shakes and knocks pretty bad. After 20-30 seconds the shakes and knocks go away. When i go to drive the truck it is very sluggish and has no power, after about 3 or 4 mins of going down the road the truck "fixes itself" and drives much better. Although you can still notice a power loss and hesitation. Ive noticed you can let the truck sit running as long as you want for it to warm and it still has the sluggish/no power problem. It is only when you get it down the road a bit that the problem gets better.
***Note*** during all this the truck DOES NOT smoke black, white, or anything.
The truck has new batteries, alternator, cps, and the fluids look fine.
Where should i start in trying to fix this problem? thanks
Based on my symptom chart for a 2003 7.3L you should be checking your engine oil level, check for oil in coolant, when was it changed last, and is it the right oil for your truck (SAE oil viscosity and API rating). Check for aerated oil. Check MAP Sensor for holes, blockage, or disconnection. Check air intake system: after filter minder. Check intake manifold system for leaks. Check for sufficient clean fuel. Check for intake restriction.
A few more things that you should test are the CMP, ICP, and IPR.
I would also do a visual and follow your fuel supply line back to the tank and look for additional inline filters or mods that may have gone bad.