MAF Sensor

[S1bolger]

Afternoon, my car has been "jumpier" and not as smooth as it used to be so I decided to check the maf Sensor after searching through forums to see what the issue could be. The sensor (metal rod) was filthy and completely black with dirt and dusty crap. Can I just clean this with a damp cloth or do I need to do it properly and buy some carb cleaner etc? Cheers.

[Jaykay495]

Use a dedicated maf cleaner spray, not carb cleaner and deffo not a cloth.

Perhaps also research the cost of a new part. A sketchy maf is just a pita.

[GreenV8S]

Maybe look into why it's getting dirty, too.

[anonymous-user]

Jaykay495 said:

Use a dedicated maf cleaner spray, not carb cleaner and deffo not a cloth.

Perhaps also research the cost of a new part. A sketchy maf is just a pita.

What he said, although I've found cleaning them rarely achieves anything. Worth a couple of quid for some MAF cleaner on Amazon to check, but as he said don't use carb cleaner and never touch the components.

[S1bolger]

Appreciate your help chaps.

[Boosted LS1]

I thought they did a self clean super heat mode upon start up? To burn off the crap.

[S1bolger]

I thought that too! But having looked at the platinum wiring its completely filthy and greasy. Got some proper cleaner coming tomorrow - see if it makes a difference. Will post back here results if I remember.

[Chromed]

As said, you need to clean or change your air filter , and check no air leaks as the MAF should not be covered in crap.

[GreenV8S]

Boosted LS1 said:

I thought they did a self clean super heat mode upon start up? To burn off the crap.

I'm struggling to imagine how that would work, or why it would be necessary.

[Boosted LS1]

The wire heats up super hot to burn the crap off. After that it can read true values of resistance, air cooling and changes in resistance. Allowing accurate mass air flow changes.

[GreenV8S]

Boosted LS1 said:

The wire heats up super hot to burn the crap off.

What crap, and how hot does it need to get to 'burn it off'? Even trace contamination is enough to screw up the MAF sensor and I can't imagine how just warming the wire up would clean it in any meaningful way - unless you're imagining the heated element getting white hot, which to me seems completely implausible for multiple reasons.

[Jaykay495]

May be implausible to you, but to the rest of us, it is just how hot-wire maf’s function.

https://en.m.wikipedia.org/wiki/Mass_flow_sensor

[anonymous-user]

I've certainly read about a post shut-off high current flow through the MAF wire to burn off contamination in multiple service/electrical guides for different cars.

I've just replaced the 15 year / 150k mile old MAF in my XJ8 due to sporadic P0101 codes with no other symptoms and no apparent problems. £75 odd for the OEM Denso part, £160+ in a Jaguar box.

Denso have a web tool for checking cross compatibility.

[Boosted LS1]

GreenV8S said:

Boosted LS1 said:

The wire heats up super hot to burn the crap off.

What crap, and how hot does it need to get to 'burn it off'? Even trace contamination is enough to screw up the MAF sensor and I can't imagine how just warming the wire up would clean it in any meaningful way - unless you're imagining the heated element getting white hot, which to me seems completely implausible for multiple reasons.

This bit from the link.

A hot wire burn-off cleaning circuit is employed on some of these sensors. A burn-off relay applies a high current through the platinum hot wire after the vehicle is turned off for a second or so, thereby burning or vaporizing any contaminants that have stuck to the platinum hot wire element.

Hence 'hot wire', fking hot sums it up.