Loss of power

[Mark S]

Hi guys, my 2.8 patrol has suddenly lost power for some reason. When driving on flat road it is fine but yesterday on a hill that i regularly travel up at around 90kph in 5th gear I was down to 3rd gear at around 60kph and it felt as it was really struggling. Temp was fine didn't get hot at all, once at the top of the hill and on flat road again seemed fine.....It almost feels as if it is restricted in some way. I checked the air cleaner/snorkel etc for blockages, exhaust seems to be fine..In my experience the feeling of being restricted can only come from air flow or fuel pump issues. I have raced and rebuilt cars for over 20 years but none diesel so this one has me scratching my head a little... Any advice on some things to check or suggestions would be much appreciated.

Thanks.....Mark

[Woof]

Have you checked your fuel filter, it could be blocked

[Mark S]

G'day Dogman, Yeah mate it has just been replaced, I may check it to be sure though. I know when I had mu 4.2 GQ ute there was a gauze filter in a union join on the fuel pump, Is there one on the 2.8 anywhere that I may not have found do you know?

[Mark S]

Would the MAF sensor have an impact on this??

[Yendor]

You could have a bad batch of fuel, have you just filled up?

Have you checked the basics, air leaks in the air intake/manifold, earthing points... etc

Yes the MAF could be the problem, in the workshop manual it will tell you how to test it and what voltages you should expect.

You could try cleaning it (do not remove the 4 screws) with some CRC electrical contact cleaner.

Cheers Rodney

[Mark S]

Yeah thanks mate, just went through the manual and tested the MAF sensor...got the battery voltage to white wire as described but red wire is reading zero where as should be showing a couple of amps so could be the problem there, tried cleaning it with no success so far.

[Yendor]

Yeah thanks mate, just went through the manual and tested the MAF sensor...got the battery voltage to white wire as described but red wire is reading zero where as should be showing a couple of amps so could be the problem there, tried cleaning it with no success so far.

Was this with ignition on?

What was the voltage reading with the engine running?

[Yendor]

Also did you check the earth to the MAF, black wire.

[Mark S]

Was this with ignition on?

What was the voltage reading with the engine running?

Yep ignition was on, voltage reading on white wire when running around 14amps....no reading on the red wire at all while engine running should be 1.3 to 1.8 amps from what I understand. I did check the earth wire as per the manual, gave them a clean to be sure....

[Yendor]

It sounds like you are on the right track with the MAF sensor.

It's just a bit strange that you get 0 volts on the red wire, I would check that the red wire has not shorted to earth.

[Mark S]

Yep righto thanks mate..

[Mark S]

Finally got it sorted...The MAF sensor was the culprit!! after testing everything possible I removed the square cover from the top of the sensor where the wiring plug fits in and found that one of the tabs on the circuit board (to the red wire) had become detached. Soldered back into place. Now reading 1.8v on idle as per specs. Refited and resealed cover....all good. Made an instant differance to the idle and the rev range and power under load. No longer feels as if labouring :).
Thanks for the advice and suggestions, much appreciated......Mark.

[Yendor]

Well that explains the 0 volts, good find.