I have an 89 mustang GT 5.0 5 speed ( 111k ) and was having these problems…when coming to a stop and in gear the car would buck, and throwing a CEL.
and also on WOT acceleration. I do not have a code reader for this car but did it manually by jumping the connector according to the shop manual.
It showed an MAF fault ( forgot the code on the CE light ). I pulled the MAF and cleaned it withy MAF cleaner. Put it all together and noticed
the clamp at the intake tubing “after” the MAP was loose, I mean really loose. I snugged that up.
Started the car and ran good but the CEL was still on…Took it for a drive and after about 1/2 mile the CEL went off.
Drove it on a 40 mile round trip speeds up to 70 MPH and no bucking, or CEL lighting up when coming to a stop or at WOT
( not burning rubber ) in other gears.
Could this be because the engine was pulling in air after the MAF throwing the ECU off as to throwing off the amount of fuel
to the injectors ? Note: I have the EGR bypassed for 11 years now ( no pinging etc on 87 pump gas )…We have no emission inspections in FL.
Just curious… Have a great day Howie in Eustis Florida.