Code 28

There is no valid code 28 for 5.0 Mustangs. Possible other codes are 27 & 29, which are VSS sensor codes.

Are you sure??

I've had code 28 before, I will look tonight in my log to see what it was. I'm thinking (off the top of my head) it had something to do with the pressure sensor (thing on the firewall) that is left "open" to atomosphere after a maf conversion...

I will check what I wrote and post tonight.
 
Are you sure??

I've had code 28 before, I will look tonight in my log to see what it was. I'm thinking (off the top of my head) it had something to do with the pressure sensor (thing on the firewall) that is left "open" to atomosphere after a maf conversion...

I will check what I wrote and post tonight.

Code 28 is VAT sensor out of range or IDM failure RH side coil. There is no Vane Airflow Temperature sensor on a 5.0 Mustang. All Mass Air Mustangs use a Mass Air Flow Meter . Speed Density Mustangs do not have a sensor for measuring airflow.

The IDM failure RH coil is a code only used in 4 cylinder cars.

Brief code definitions can be found at http://www.troublecodes.net/Ford/

Here's a book that will get you started with how the Ford electronic engine control or "computer" works.

Ford Fuel Injection & Electronic Engine Control 1988-1993 by Charles Probst :ISBN 0-8376-0301-3.

It's about $20 from Borders.com see http://www.amazon.com/ . Select boo... black/white wire for the ground for the DVM.