Hey guys new to the forum! I’ve got a 93 ranger with the 4.0! I’ve put a lot of time in this thing including a new engine! It’s throwing maf codes after maf codes! Once I replace with a new one it’s good for about a day and then the maf codes come back! Any ideas? I’m plum out of them, I’ve been trying to figure this out for about a month now

 

What's the actual code # ?
There's more than 1 for the MAF, and they all mean something different.

 

Code is a 157- low voltage. I’ve checked the wiring and I’m getting 5 volts to the sensor and this is the third one in 3 days. It just doesn’t make any sense. And thanks for the response!