Air flow meter repair

[sundevil64]

I did a search and found one decent link to try to repair a worn air flow meter. Does anyone have any more info on this?

Thank you in advance,

John

[DRACO A5OG]

Before you attempt the repair, get your DVM and 9volt battery to test if in fact you have dead spots on the arm travel.

Here you go: Rejuvenating a Bosch Motronic Air Flow Meter - YouTube

[Tippy]

What are your symptoms? How do you know you need repair?

[sundevil64]

Thanks DRACO.

"Tippy",

I recently have unexplained hesitation with throttle input. It's on an 84 ROW 3.2 motor that has an unknown but thought to be a high amount of mileage. The problem exhibits itself early on in the acceleration (2k-3k range). I did the easy thing and swapped it out with another AFM that was known to not have any hesitation in this range. It went away, only to have a hesitations at about 4400rpm. It seems to me a safe assumption it is the afm.

[Tippy]

But you still have hesitations. Might be more to it.

I'm having similar problems and went down this path too.

Good luck and please let us know the outcome.

[dshepp806]

As to fuel: make sure you've got good pressures

As to AFM: open her up and have a look,..just don't touch that frckin' spring......look, under magnification, at the resistive trace,..it is not too difficult to make it grab fresh copper

As to ignition: all fresh plugs, dist , healthy coil...

Any of the above breakdowns could manifest your symptoms.....(good mixture, too).

BEST!

Doyle

[sundevil64]

Well the afm was replaced with two different ones including one rebuilt. I'll have to go through the list. My next guess is going to be fuel pressure. Time to break out the book. I guess a cap and rotor can hurt either.

[BGCarrera32]

Step 1 is to get access to a wideband O2 sensor and find out what the exhaust gas says about the engine at those rpm ranges...it almost sounds like your hesitation might be a lean miss. If you're north of say 15:1 that might cause a miss. Swapping AFMs won't tell you much as the base mixture screw is probably not set exactly the same form one unit to the next.

[sundevil64]

I'll check the afr's as well. Is there a mixture screw? It's an 84 with efi.

[BGCarrera32]

There is a 3mm hex buried way up underneath the lower left corner of the AFM box as viewed when looking at the engine from the back of the car.