Mass air flow 99. Mustang gt issue

Jasoncharles

New Member
May 11, 2019
11
0
1
38
Wisconsin
I have a dumb question is the maf calibrated or the ecu? I have read a couple contradicting posts. I have 99 gt procharged running good then all of a sudden once in a while it would just go lean out of nowhere happened maybe once a week. Then it started to and got bad started happening 2 in my way to work so I took it off and cleaned it . On my way home it was really bad shutting off , idle surging and going lean. I just have a car quest maf on it from 01 lightning so I took it and warrantied it but now it’s worse is there a reset procedure?
 
  • Sponsors(?)


93 331 GT

Member
Mar 5, 2006
60
0
7
Jackson, NJ
I have a dumb question is the maf calibrated or the ecu? I have read a couple contradicting posts. I have 99 gt procharged running good then all of a sudden once in a while it would just go lean out of nowhere happened maybe once a week. Then it started to and got bad started happening 2 in my way to work so I took it off and cleaned it . On my way home it was really bad shutting off , idle surging and going lean. I just have a car quest maf on it from 01 lightning so I took it and warrantied it but now it’s worse is there a reset procedure?
Hello. The ECU is calibrated to the stock MAF. I run a Lightning MAF in my car with an SCT Tuner. in the OBD-I days all you needed was matching injectors and MAF. Not the case after 1996. Your Car is not seeing the proper air/fuel mixture. Also your injectors need to be properly sized as well.
 

Jasoncharles

New Member
May 11, 2019
11
0
1
38
Wisconsin
The ecu has been tuned for the 90 mm maf and 42# injectors. Am I even benefit from the 90 mm maf if there’s a 3” piped in front of it and a3” pipe on the outlet?