94 ranger 4.0 engine flash code help

[noah_trivitt]

Hey everyone I have a 94 ford ranger that starts fine but when have throttle it develops a miss and won’t idle. We done the flash code due to check engine light on and no one around us has a obd1 scan tool. We got 111 151 and 251 flash codes. I’m unsure what the 151 and 251 is. The truck recent had new plugs and wires and coil pack installed. The truck also is showing good fuel pressure. Any help would be appreciated

 

[RonD]

Welcome to TRS

151 and 251 are not valid 3 digit Ford codes

So maybe you saw/counted them wrong?

Here is a 3-digit Ford list: https://www.therangerstation.com/tech/obd-i-diagnostic-trouble-code-dtc-applications-ford-3-digit-codes/

Clean the MAF sensor, every year
Replace O2 sensors every 12 years or 100k miles, which ever comes first

You can pull out the computer and open it up
There are 3 barrel capacitors that can fail/leak which will cause running issues, easy to replace, under $5 fix
This could also cause CEL and odd codes

Like the 3 blue capacitors in this picture: http://www.auto-diagnostics.info/ford_eec_iv

I had to do this on my 1994 a year or so ago

 

[rumblecloud]

While you're checking the computer, check that the ground wire is not corroded. Even if t looks okay, clean it up anyway. It's an easy job.



Mine was giving me fits for months until I decided to follow Ron's suggestion to pull the computer. On the way to pulling it I corrected the corrosion on the ground and I haven't had a problem since. (crossing my fingers and hoping I didn't jinx it now).