My 1997 4.2 has a check engine light on. The generic codes are 1537 and 1538. I checked with the mfg of the scanner. They said the codes indicate clogged intake manifold runners, both left and right. Any idea what this means?????

 

These codes indicate that your intake manifold runners are stuck open. Possible problems include broken bushings on the actuator rods or one or both of the vacuum motors are bad. Unfortunately the vacuum motors are $230 each and are most likely dealer only. The bushings are $6 each. Four total. The worst part is the upper intake has to be removed to access these parts. They are on the rear of the intake manifold. If one of the motors doesn't hold vacuum, both will stay open. Only way to test is to access them and pull a vacuum on the diaphram and see which one does not move.

Robbie


P.S. The runners default to open with no vacuum.
When vacuum is applied, they shut.

 

Thanks for the info. I'll have to think about doing this myself or take it to the local garage. The temp outside is 35 degrees!!!!!!!

 

Just to give you guys a heads up. As I was replacing the spark plugs back to motorcraft, I noticed what looked like broken wires in a connector between the fire wall and battery. These ended up being broken PLASTIC vacvum lines. I bought rubber hose and repaired them. All codes cleared and so far are still off. Also the truck runs smooth.