1995 exp 4l cel on

[slsnut]

Car sat for a month and out of the blue on first start the CEL came on after 1-2 min. Shut car off then restarted and CEL came on again after 2 min or so. Checked the fuel cap and it was tight. Vehicle has 76K original miles. I did notice slight surging at around 50 MPH today. It has a connector but my OBD II scanner won't read the codes from it. I Will either read codes using CEL flash method or borrow one from Auto Zone. Any clues at this point would be appreciated. Will report back when codes are in hand.

 

[swshawaii]

Posted 21 minutes ago.
http://www.explorerforum.com/forums/showpost.php?p=3526856&postcount=4

 

[slsnut]

Oh Wow Mahalo Braddah!

There is a wealth of information here for me and others.

SLSNUT

 

[slsnut]

Ok, new information on the CEL condition this morning. On my 20 min drive to work CEL cycled on and off several times. I noticed a gentle engine surging at 40 MPH after which the CEL came on then went off after surge went away. When I parked and let idle with CEL on I noticed gentle surging which caused the RMP to hunt about 50 RPM bit around 900 RPM. Have not pulled codes yet.:roll:

 

[slsnut]

More new info: Pep Boys does not have a OBD I tool to loan & Auto Zone and O'Rileys do not loan OBDs any more around here. I went to pull codes using the CEL and was surprised to learn that the CEL did not flash even once during the KOEO and KOER tests. When the CEL did come on as it has been after a minute or so, the engine ran up to 1500 RPM, CEL went off then when idle returned to 900RPM (and hunting 50 RPM) the CEL went back on and stayed on. I re-checked my jumper connection several times for continuity and to be sure I was done right IAW the pictures on the site here. Now I'm really stumped! HELP!

 

[slsnut]

Ok, bought the Ford OBD1 Reader on Amazon ($30) and got a single 337 Code for the KOEO and left in memory as well. Code is "EGR CIRCUIT HI VOLTAGE". Any advise on where to start other than pulling the EGR valve? Anyone else received this code and done the repair to clear the code?

 

[J_C]

Before pulling it, check that the vac hose is on good at both ends and not damaged in between. IIRC, a high voltage condition can result from it getting clogged up so you might try cleaning it out.

 

[slsnut]

Thanks for the tip, however the problem was traced to EGR DP sensor. Replaced with one from Amazon and fixed CEL, surging and idle speed stumble. Car runs much more smoothly and accelerates better.