Help - Pajero turbo pressue drops to 0 on throttle

[geaddict]

I have a 1995 Pajero 4m40. Turbo was getting worse and worse. More black smoke and i noticed throttle would cause boost pressure to drop. I was starting to climb hills at 40km per hour instead of 100 to 110 and pushing. This was a replacement turbo that a bad mechanic said I needed for another issue a few months back. It was not the problem and it was changed for nothing but to make the mechanic twice the money he quoted to solve a problem he never did. About a month later I noticed the power getting weaker and the truck has slowly gotten to the point it is now.

When I am pushing the vehicle (throttling hard) a lot of black smoke and no power. Lighter pressure still means no power but way less smoke. On the flat sections of highway no issue. Vehicle runs and pulls to speed (if slowly). On hills, very slow. From dead stop, very slow. Strangely if I place it in a lower gear, no power and turbo goes to 0 practically. Put the tranny in the hold position and the turbo power is higher through most gears but still not up to par.

Had the turbo changed back to my original. Still the same.

What am I failing to see here? Help please!!! I use this vehicle daily for work!

Geaddict

[mararmeisto]

Did you check the air intake, air filter? If that's too dirty, not enough air will be getting to the turbo.

Intercooler tubing on top - got a hole? Not connected properly?

I can't think of anything else. The turbo really is one of the simpler parts of the engine.

[legionnair]

Is the waste gate being held open? Is your blow off valve stuck open? Is a charge line ripped? Pull off the exhuast side of the Turbo check to see if it spins easy and for damage to the fins. Then start it and see if it spins with some one reving it up.

Lots of questions need more answers

Dustin

[nxski]

Any ticking sounds? I had similar symptoms when my exhaust manifold was leaking although I have no idea what my boost was at.

[Big-Bird]

I agree that you should check and see if the turbo spins easily or not.
Disconnect the hose between the turbo and the intercooler and spin with a finger.
See if that bypass line, I suspect you T'd into for your boost gauge, is still connected properly or if its worn through.
Check the entire bypass line that runs to your injection pump.

Did you check your EGR system? A hole in that valve will cause this kind of havoc as well. My friends 4M40 equipped Paj did everything you described and it was his EGR blanking plate. It had developed a large bore hole....stupid thing had given him greif for 2 weeks before he found it. Replaced the plate, it ran like new.

[geaddict]

Problem was solved when the original issue was fixed (we have had this for a while). The oil that was spilling out the valve cover breather from the factory defective valve system had been replaced a few days before. Now the oil was clearing from the intake system and intercooler. We could never even come close to keeping it out before even with a catch can. As that improved the power began coming back. A clean out of oil trapped in the boost compensator and a super cleaning of the air cleaner (gunked up with oil as well) did the trick. 90 to 98% power restoration depending on the gear. Now I just need to address the tiny leak discovered in the inner clamp area of one hose at the intercooler, possible slight filter constriction on my veggie filter side and I will convert the air cleaner system into a snorkel to force even more cooler air into it. My EGTs are also down a good bit now as well.

Thanks for all the suggestions!