koolhand

Went through and fixed major leaks/replaced MM hose, tightened clamps... Spun turbo when I had hoses off and noticed that turbo did not spin all that freely... felt like it was slightly hung up or something... When I put 'er back together, boost was back to just barely better than before, about 1.2. Yeah, I know, that sux. New problem is the dropping off of the boost. Boosts fine and intermittently, boost will drop to 0.4-0.5 until I take my foot out of it and feather it back to boost. From search, sounds only slightly similar to the situation when overboost is detected.
Does this sound like the K26 is on it's way out? Engine has 190K on the clock and I know, invariably, it's gonna happen sometime.

Any info greatly appreciated,

Luke

jurq

Try your solenoid output tests. Could be your waste gate freq valve.

Eric NY

Run codes!

aerohr

and a ground from any piece of grounded metal... touch a lead to each terminal of the waste gate frequency valve. Does it click open/closed? If not - it has likely given up the ghost.

The turbo should spin pretty freely - if it "catches" on something - thats a bad sign.

boxerfan

If you only see 1.2bar then the ECU isn't assisting the spring for boost control via the WGFV. This can also happen with a failed MFTS. Pull codes and run output tests to check the WGFV. HTH.

koolhand

Just gettin' a chance to log back on...will run codes and check 'er out this weekend. Thanks for the help guys.

Luke

koolhand

Well had a buddy who works on these a bit more than I do look at it this weekend. He said he thinks the turbo should be fine...anyway, appreciate the help.