Hey Guys,

I'm working on my buddy's '94 GT 5.0 and it has developed a strange idle. If you sit w/ it in drive for a minute the engine starts to lope a bit, but it's perfectly fine at all other engine speeds.

Shortly after it started doing this the check engine light started popping on occasionally & then going out. I ran the codes and got a 172 & a 176, which list as 172 (R,M) Oxygen sensor not switching - system is or was lean - Single, Right or Rear HO2S - Fuel control and 176 (M) Oxygen sensor not switching - system is or was lean Left or Front HO2S - Fuel control

So the computer is showing a lean condition left, right, front, and rear, apparently only occasionally because the light only comes on once in a while when driving.

Can anyone tell me what these codes mean & where I should look for a fix? My buddy needs the car in two days to drive home to see his family for the Holidays!!

Thanks!

 

Double post:

https://mustangforums.com/forum/gene...ml#post7334542