MAF Sensor going bad?





I've been doing a bunch of tuning and data logging over the past year and a half. Recently, every now and then I get a strong hesitation and/or backfire while going from very light throttle to full throttle. It doesn't happen when I hammer it, but when I am somewhat slowly pressing the pedal down.
I took a look at my data logs and found that the MAF voltage reading momentarily drops to "0" when this backfire / hesitation occurs (and then comes back up). Until recently, I've never seen that in the data log (and hadn't encountered the hesitation / backfiring either).
Could this be the beginning of the MAF sensor going bad? There are no loose / worn wires, connections are clean, etc. The MAF is the original from 1987, though I removed the screens and heat fins several years ago (never had any issues until now).
What do you think?
Thanks!
Dan
Sounds similar to mine before it failed. Mine MAF signal began to drop out randomly with increasing frequency, until it was basically undriveable.
If its only an occasional drop, you may get away with more filtering of the MAF signal for awhile.
You can reduce the multiplyer for the MAF sliding filter to increase the filtering effect and it may help it live through the momentary drop outs.
From $32B:
;--------------------------------------------------
; Mass Flow Filter & Limits
;
;
;--------------------------------------------------
LC6ED FCB 32 ; Mult for sliding filter





Thanks for confirming. It is just as you described - a momentary drop in the signal. And it does seem to be happening a little more often.
I'm using $6E and can't seem to find anything like the "Mass Flow Filter and Limits" table in TunerPro RT. Would it be called something else?
Thanks so much!
Dan
From $6E:
;======================================= =======
; MASS FLOW FILTER & LIMIT PARAM
;
;======================================= =======
LC5FD FCB 32 ; 32 mult, SLIDING FILTER MULT
With my Ford MAF, I've gone as low as 4 on this value since there seems to be less hardware filtering on the input circuit that I'm using for the Ford MAF.
I've tried, 16, 8 and now 4 with good results.









