MAP sensor?

[robert1]

I have a 92 ranger 4.0L and it is hard starting and runs very rough when it does start.I am fairly handy when it comes to engines however I am lost on the MAP sensor. I can not find one on this truck. Is there one and if so where do I find it?


Thanks,


Robert

 

[Mudhound]

Have you tried looking at the firewall, passenger side, next to/above the heater box?

 

[Sasquatch_Ryda]

The MAP, is known as a Barometric pressure sensor on your engine. Its only job is to compensate for altitude changes.

The MAF sensor located just after the air box is what does all air metering for fuel mixture.

 

[robert1]

I tried the MAF sensor and it is still hard to start ,runs rough ,and stalls. The voltage readings for the MAF are good as well. I really need help to solve this problem. It doesn't have a diagnostic connector, it was cut off when I got the truck. I tried the MAF sensor, fuel pump and filter, coil pack, wires, plugs, crank sensor, TPS but nothing helps. I thought maybe MAP sensor because of the way it was acting , but if it doesn't have one than that is not it and that is why I couldn't find it.If anyone has any thoughts on this please help.


Thanks,


Robert

 

[Sasquatch_Ryda]

Have you checked the IAC?

 

[BRUTUS_T_HOG]

The Baro sensor can actually cause major running issues.

To check it use a multi meter on HZ and check the signal wire key on engine off. It should have about 159HZ at sea level.

 

[robert1]

No I haven't checked the IAC or baro sensor. I will check these on Tuesday and let you know. Thanks Guys,

Robert

 

[robert1]

I tried the IAF sensor. When I unplug it it runs extremely rough and stalls. I took it of and cleaned it with carb cleaner and it didn't run any different. I don't have a bero sensor on my truck ,Just a MAF which I checked and cleaned and it is OK

 

[frankgeno]

Robert1, did you solve your problem from 2012? if so what was the solution as I have a 92 ranger 2.9v6 and same trouble, idles rough and going down hill holding the throttle / speed steady the engine jerks and runs rough, pulling up a hill it seems to run fine.