MAF question
Thread Starter
Intermediate
Joined: Apr 2014
Posts: 40
Likes: 0
From: Phoenix AZ
MAF question
So I've been trying to chase the Gremlins out of an 86 coupe that I bought in the late spring. I've had a rough, hunting idle with sporadic backfiring and running very rich. I've already replaced wires, plugs, cap, rotor and coil. Also installed a new O2 sensor.
The PO gave me a moates data logger with the car and I just got around to getting it connected and running a first scan.
On the scan it would not start but I did data log the numbers.
TPS sensor was reading .77 volts so I dialed down the airflow screw until it reached .54 volts.
Do these numbers look correct?
IAC - 144 Steps
Coolant Temp - 93.65 F
BLM - 128
O2 - 452.88 mV
Airflow - 5888
I'm thinking the MAF is the culprit but I don't know what number I should expect during cranking.
Thanks.
The PO gave me a moates data logger with the car and I just got around to getting it connected and running a first scan.
On the scan it would not start but I did data log the numbers.
TPS sensor was reading .77 volts so I dialed down the airflow screw until it reached .54 volts.
Do these numbers look correct?
IAC - 144 Steps
Coolant Temp - 93.65 F
BLM - 128
O2 - 452.88 mV
Airflow - 5888
I'm thinking the MAF is the culprit but I don't know what number I should expect during cranking.
Thanks.
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
The BLM of 128 is the default value in open loop mode. You are operating early in the warmup sequence and the ECM has not gone into closed loop mode yet. That won't happen until the O2 sensor warms up.
