Maf?

[Jadenjdawg]

I have a weird issue, which i have come to believe to be an MAF problem. 98 4.0 with automatic transmission. Sometimes, if I idle for ten minutes or so, the idle becomes extremely rough. It will carry on once you take off, for the next 20 or 25 miles, and run very rough at all speeds. Then, it goes away and will purr like a kitten, until i Idle for ten minutes or so again. It happens sometimes daily, and sometimes once every couple weeks. The other day i was changing plugs and wires, and unplugged the MAF sensor because it was in the way. When I was done, I forgot to plug in the MAF sensor, and the engine ran great, idled better than ever and ran great on the road. The only problem was the transmission acted wired between first and second, and second and third. I plugged the MAF sensor back in, and the transmission wierdness went away, but the goofy idle and loss of power came back. Does this sound like a bad MAF sensor, or something else?

 

[jeremysdad]

Try cleaning it and see what happens.

 

[RonD]

Yes, clean the MAF sensor
Read here: http://www.therangerstation.com/tech_library/CleanMAF.shtml

When the MAF sensor is unplugged the computer(which also controls the shift solenoids in the trans) goes into "limp" mode, it means the computer believes there is a major failure but instead of shutting down everything it allows driver to "limp home".
Transmission shifting is also in Limp mode

You should have also gotten a CEL(check engine light) while running with MAF sensor unplugged?
If you didn't get a CEL then it could mean another issue