Hi.

I had assumed, in error, that the recent warning light was due to the same problem of wires shorting out and causing exhaust sensor faults. It's not and it's now two different errors, and I'm guessing at what to look for so hopefully looking for confirmation or a different suggestion.

 

Codes P0299, Turbo underboost. AND p006a MAP/ MAF correlation error.

I have previously checked the turbo, and the variable nozzle mechanism seems smooth. I've previously replaced the inlet pipe from the intercooler to manifold. The intercooler pipes seem OK, no oil spray to indicate a split / leak.

The car will perform well at times, and when it does it seems to have all of its 197HP at both low speed and main road driving, So, I'm ruling out intercooler holed and boost pipe split.

Then at times, I get a misfire (if it were a petrol car, I'd say weak spark), and then when pushed it will throw up the error and go into limp-home. Some times I can re-start and it will be fine, others not so. The other day it was in limp-home, I went to sport mode in the auto, and went home at 2-3k rpm, by the end of the journey it was fine and re-started and has since run well.

 

My guess- does this seem logical?

I'm thinking EGR not closing fully when it should, or boost sensor. The two codes together make me think that some of the boosted air is either flowing to the outside of the system (such as with a split pipe) or out of the inlet side of the engine (so leaking through the EGR to the exhaust). The fact it's intermittent and definitely not just at times of higher boost, makes me think it's not a split pipe (such as the one near the turbo) or similar.  If it was MAF, then I'd have thought I'd not see the p006a fault (as there would be a decent amount of boost). I can take the boost pressure sensor out and check for blockage (but again, bit of doubt due to intermittent nature), but the EGR looks to be a PITA to access, so I was thinking of a blanking plate and so physically prevent any leak of boosted air.

 

Thoughts?

 

 

 

Oh dear, silence.

I guess that means nobody has encountered that combination of codes.

 

Anyway, I spent some of the day checking a few things, no obvious blockage on manifold pressure sensor, the only thing i found was black tar-like residue (the sort you get when an injector seal goes), at the head-manifold joint. When checked, one bolt securing the inlet manifold was loose, so all I've managed is to tighten that and clear codes, now hope for the best.

Just came across this because both those codes p006a and p0299 have shown up on my Ford Ranger PX2 2.2L and everything you've said sounds the exact to my issues like how it goes into limp. Did you ever find out what the problem was and how to fix it

11 hours ago, Kai132575 said:

Did you ever find out what the problem was