MAF Cleaning

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Does anyone have experience cleaning Bosch mass air sensors? They get contaminated by dirt, oil, silicon, or potting compound from the sensor itself. I've read conflicting reports about cleaning them with alcohol, electrical contact cleaner, carburetor cleaner, and circuit board solder flux removal solvent.
 
If its already throwing a code, I'd try and clean it. Probably with flux remover or contact cleaner. I would'nt touch a properly functioning one, as they are rather expensive.
 
Clean it with something that leaves no residue. I know for a fact that CRC contact cleaner leaves no residue.

You could also spray whatever you're planning to use on a sheet of paper and see if it dries without leaving a trace.
 
quote:

Originally posted by brianl703:
Clean it with something that leaves no residue. I know for a fact that CRC contact cleaner leaves no residue.

You could also spray whatever you're planning to use on a sheet of paper and see if it dries without leaving a trace.


Very simple yet good way to test.
 
I tried cleaning the MAF sensor on my VW with 91% Isopropyl alcohol when it threw a CEL last year. Cleaning it did no good. It was D.R.T. At least it was replaced for free by VW.
 
It was the CRC electrical cleaner. It is NOT safe for plastics, so look for cans that say that they are.

I have two Taurus sedans.
 
I've tried CRC and a number of different contact cleaners for various relays we use at work.

The test I use for residue is spraying it on a mirror...some that claim to not leave a residue are leaving //something// behind...
 
I recleaned mine a couple of days ago, after tracing some non-code symptoms back to the MAF. I looked carefully at the sensor with a 10X eyepiece (25mm ocular from a trashed pair of binoculars), and noticed that the previous cleaning with CRC electrical cleaner had still left dirt. The MAF has two fine wires wound around glass cylinders, and they're fragile (expensive). First of all I noticed that the 'automotive' CRC melted some types of plastic, so I'll be getting rid of it as it chemically welded some connectors togther. A lot of patience and swearing got them unstuck. I used a Testors model paintbrush (very low force) and some +90% alcohol to clean the MAF, verified with the eyepiece. After reinstalling it I pushed a straight pin up into the connector trying to hit the metal contact, adjacent to the signal wire, and verified that it was producing acceptable voltage at idle (almost 0.9 volts for mine).
 
quote:

Originally posted by 1sttruck:
First of all I noticed that the 'automotive' CRC melted some types of plastic

Is that CRC carb cleaner? The CRC QD contact cleaner I use is safe for plastic, according to the label:

A petroleum distillate / alcohol based precision cleaner designed as an alternative to CFC based cleaners. Ideal for apps where lower flashpoint materials can be tolerated. Cost effective, plastic safe & residue free.
 
contact cleaner is not safe for some plastics. it will remove the plasticizers and the plastic piece will crumble/crack.

try some throttle body (not carb) cleaner. throttle body cleaner is sensor safe which means it wont harm the o2 sensor or destroy any plastic sensor housings it might contact.
 
quote:

Originally posted by 1sttruck:
The MAF has two fine wires wound around glass cylinders, and they're fragile (expensive).

In case you were curious, guys, these fine wires are called strain gauges. I've seen someone at my university try to fix one of these sensors and they are very hard to soldier together. You'd probably need some flux and for sure a fine-pointed soldierer if the wires break. The flux remover spray does melt some plastics. I believe the flux remover spray contains acetone. Pure acetone would be the ideal cleaner if the MAF sensor wasn't made of plastics. I believe brake cleaner, throttle body cleaner and carb cleaner will also melt plastic. To be sure your cleaner won't dissolve your plastic sensor, take an old, cheap plastic toothbrush and soak it in your cleaner. If the toothbrush doesn't melt then you won't have a problem
 
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