Howdy people,New to the forum here and have a problem.I have a 1993 Ranger with the 4.0L engine.It has started to run really bad.Check engine light on,loses power, cuts out when you stop,black smoke coming out of the exahust,bad milage.Get the idea?I have an actron code scanner and the codes that came up are.158-MAF signal voltage is too high,159-MAF signal voltage is higher or lower than expected,173-HEGO voltage signal indicates "rich"(Bank # 1),177-HEGO voltage signal indicates "rich"(Bank # 2),185-MAFsignal voltage is lower then expected.
There we go.It looks to me that the MAF is either dirty or no good any more.That seems to be what would cause all of the afor mintioned codes.
Have checked all the vacume hoses, the air filter, removed and cleaned the MAF,all look ok.After that I removed and then replaced the positive battery cable to "reset" the computer.The truck runs the same but with no check engine light anymore.How can I check the MAF to see if it is working before I spend $130 US for another one?Or is there something I am missing here?Thanks.

 

I would also check the electrical connections to the MAF and make sure theirs not a short or something.

 

OK, I have a 94 4.0 Ranger. The same two errors came up - 159 and 177. Replaced both MAF and O2 sensor. Ran great for about 10-15 miles. Same codes come back up and it runs bad and smokes again. What would cause both to show errors?

 

BTW: It has not had a CAT on it for the last few months. Could it be related?

 

i'm having same problem with my 1993 ford ranger xlt i dont have a scanner but i did the flashes. Mine are 169 & 159 dont know what they are for, rough idol & black smoke im lost!!

 

i have a new mass air flow just bought broke me, tried coil pack, tps, it dont make sense run great then started messing up, not vacum to fuel regulator but if i add vacum truck runs worse