Check engine question?

[MY 85 GT]

I know why the check engine light is on, it has to do with the EGR sensor and a sticking egr valve...i am waiting to get some extra money so i can do a PI swap so can i disconnect the battery for now to shut the light off i know it stores it but i can clear it after i do the PI swap if it comes back on i can just disconnect the battery again..So can i do that to get rid of the LIGHT?...

 

[wmburns]

Sure you could do that. Bear in mind that each time that is done it will reset the PCM readiness tests as well as the idle/fuel trim values. The effect of this will be:

* Car will drive/idle poorly as the trim values are being re-learned.
* Automatic transmission will shift harsh as shift points are re-learned.
* The car will NEVER pass inspection because the readiness tests are not complete.

In my experience working with EGR problems, the DPFE sensor is the cause about as often as the EGR valve itself. If the vacuum hoses to the DPFE leak, this will cause DTC's. Also, Ford changed the calibration values to reduce false positives. The problem is esp bad with the metal version of the DPFE.

I personally have replaced more good EGR valves only to find out it was really the DPFE sensor all along.

 

[MY 85 GT]

Thanks for the info..I have the plastic DPFE already and yes that is no good either i have an old one on there now that was given to me to use for now until i got the money to replace the EGR valve and that senso..so you think i should just leave the light on?...or can i go to say Advanced to have them clear it?...

 

[wmburns]

Why? It will just come back after a few drive cycles. Besides, reseting the PCM with a scanner will have almost the same effect as disconnecting the battery. What's the point? If you know what the problem is and don't want to fix it, ignore the light.

 

[MY 85 GT]

Why? It will just come back after a few drive cycles. Besides, reseting the PCM with a scanner will have almost the same effect as disconnecting the battery. What's the point? If you know what the problem is and don't want to fix it, ignore the light.

Well im kinda short on cash right now and im saving up to do a full PI swap and then i will buy the new EGR valve and sensor...then...so i had the computer reset before when the shop i use found the problem the car seemed to run ok after that..so basically disconnecting the Battery is the same as resetting with a scanner?....