Hi guys,
I need some help diagnosing a problem that is causing the check engine light to come on. I am coming up with three EGR related codes. (32, 33 and 34) I'm also getting a couple of throttle position sensor codes among other things. Here's the strange part. We drove the truck out on the highway for over an hour without the light coming on, but we couldn't have been in town more than a couple of minutes before the light was on. Does that sound EGR related to you? We have a spare 302 available from an '88 F150. Would the EGR setup from that motor work on my truck? (91 5.8L) Anyway, thanks for your help guys.

 

With Codes 32,33 & 34. The problem most likely is the Egr position sensor . Its mounted on the back of the Egr & detects when its opening & closing . Its a potentionometer sensor that varies its signal according to the egr valve position . What are the other codes youre getting concerning the TPS ? Verify that you have reference voltage & signal return at the sensor harness ( 4 to 6 Volts ) Also check the sensor resistance . The codes may also set if the egr is not seating properly . Carbon may prevent it from seating properly .

 

As you can tell, I'm a little new to all of this. When I read the codes, I get three codes, then the same three are repeated before going on to a string of different codes. Did I understand correctly from the manual that those three codes identify current problems and the others represent problems that have been corrected? Thanks for your help. Hope this wasn't too confusing.

 

The computer only shows trouble codes.

 

Wouldn't you know it. Looking for something complicated when the solution is really very simple. My dad and I were checking various things and noticed that someone had redone some of the vacuum lines to the EGR valve and used pieces of hose that were too large in diameter, therefore creating a vacuum leak. We replaced them with pieces of hose of the proper diameter and didn't really think about it any more. But lo and behold, my check engine light hasn't come on since! Thanks for all your help guys.