I have a 95 f150 351 with an auto trans. My truck runs fine, but all the sudden it had a check engine light come on. I know it didn't have any memory codes because I hade clear the codes when I baught the truck 3weeks ago. The koeo codes are: 122, 126, 128, 172, 327, 334. I know what they all mean. I just don't understand why they would all show up at one time. Any thoughts? Thanks.

 

I do believe a major vacuum leak would cause all of those at once.

 

I will check everything out when I get the chance. I would think it would run rough, but stranger things have happened. I also cleared the codes and I'll wait for them to come back. Thank you.

 

I disgaree....a vacuum leak will not affect the TPS output (Code 122). Same for many of the other codes.

 

Many of those codes come from sensors that use the same VREF signal from the CPU. Use a DVM to measure that signal at any one of the sensors. The TPS is easy to gain access, start there. It should measure +5 VDC +/- 3%

 

X2^^
Does look like the electrolytic capacitors have had it in the PCM.
So bad computer or change out the electrolytic capacitors.

 

Well the codes haven't came back. Maybe it was a fluke, but if I see them agsin, that will be the first place I check. Is it the computer under the dash your talking about? Thabks

 

The PCM computer is located in the drivers kick panel but is removed from under the hood.



/

 

Thanks for the picture. I got code 172 back today. I couldn't find a vacumm leak any where. Could the 02 sensors be reading bad. What should I look for now?

 

The capacitors in the computer (PCM)

 

^^^ I agree.