Alfa Romeo Forums banner

1 - 3 of 3 Posts

·
Registered
Joined
·
18 Posts
Discussion Starter #1
Bought an 85 that has been sitting a few years. Cleaned tank and replaced fuel pump. Have checked/replaced vacuum lines and hoses. Car starts and dies if I have the Airflow Meter plugged in. If I disconnect the Airflow meter, the car runs fairly smoothly. I do not know if it has power or not, but it sounds fairly strong when I accelerate.
Do I need to find a new Airflow Meter? The one on the car has had the lid opened and the cap on the idle adjustment is missing so I think it has been tampered with before.
Thanks!
 

·
Administrator
Joined
·
17,370 Posts
Sounds strange. The computer needs the AFM's info to calculate how much fuel to inject. Usually they will idle OK with it disconnected but not accelerate well.

It was common 'back in the day' to fiddle with the spring tension on the AFM's flap (under that cover) in an attempt to get the computer to deliver more fuel. It was more likely that the AFM was messed up than improved.

The small adjustment cap is less vital. It allows for some fine tuning of air to bypass the AFM for idle emissions. As long as the bypass screw is still in place (peek inside where the cap would fit and look for an allen head screw) it'll be OK. The cap was just to prevent tampering. It need not be replaced.

Since the cover over the AFM's flap has been removed before, I suggest you carefull pry it off. Check the printed circuit board for tracking along the semi circular area where the arm slides. Breaks or wear there can make the AFM act flukey. There is a fix that involves resetting the arm on the pivot so it bears against an unworn portion of the circuit board.

With the cover off start the engine and see if the AFM's flap seems to 'flloat' on the air flow. If it oscilates back & forth the spring tension is too loose.

More reading here: Bosch AFM
 

·
Registered
Joined
·
18 Posts
Discussion Starter #3
Thanks!

Thanks, Eric for your response, especially the AFM link. I will continue to work the problem. I checked again and it does indeed seem to rev the engine smoothly with the AFM disconnected.
 
1 - 3 of 3 Posts
Top