wont start?? OBD won't read?? need help!!

[Exporer91]

I have a 98 Ford Explorer XLT. The problem started about a week ago, while I was driving, I stopped for a red light and when I was about to take off, it lost power. Made it home and plugged the scanner in and said that the ignion coil pack was blown. I replaced it, and away I go. A few days later, same thing happened again, scanned it and again same problem, with two mis-fire codes. So ok, changed it once agian and checked the spark plugs to make sure they were tight, sure enough two out of the six were loose. few days later the same thing, but this time it wouldn't start, just died. Towed it back to the house and plugged the scanner in and it wouldn't verify the vehical at all, just said "make sure key is on", "unable to read". I know its not the scanner, because i used it on my other Explorer and it worked fine. So i know that the coil in blown, once again. but why can't i read anything with the scanner? would the main computer be the problem or a fuse???

 

[rwenzing]

So i know that the coil in blown, once again. but why can't i read anything with the scanner? would the main computer be the problem or a fuse???

Check fuse 5 in the dash panel. It is power for the Data Link Connector in your 98 Ex.

 

[2000StreetRod]

Which engine?

Which engine do you have?

You may have a bad ignition control module but that doesn't explain the OBD port problem. The 1995 and earlier models had a separate module but in 1996 the ignition control function was incorporated into the PCM with an integrated circuit. You may not have reliable power to the PCM.

I suggest that you perform the Engine No Start Procedure. It includes a link to a procedure to verify that your PCM has power. The procedure is written for my 2000 Sport but I think the wiring is similar to your 1998.

 

[marragtop]

Does the CEL come on when you turn the key to the ON position? If not, check the PCM relay.

 

[Exporer91]

CEL dose not come on. when i turn the key, it turns over but dosn't fire. thats the ignition coil. Im going to check fuses but i dont think thats the case. because when i plug the scanner in, it turns on. so there is power, but its not letting the scanner read anything about the vehical. so i dont know if there are any other codes that pop up. going to change the coil in a few min. and see if i can see anyother problems. you think this would be hard lol

 

[Exporer91]

Well, took a look at the fuses and number 19 (PCM) in the interior fuse box was blown. I looked under the dash and found that one of the wire in the ignition harness (yellow/light green) might have been grounding out. There was a camand start installed once befor, but was taken out and so I fixed that problem. I installed another used coil from the junk yark, and it ran alittle rough for about two minutes, then started running smooth and no fuses let go. After about 5-10 minutes of running, check engine light came on, scanned it and P0351 (ignition coil A primary/secondary circuit malfunction) came on. So i took out the coil, and plugged in the last one and it started blowing the 19 fuse agian, I'm guessing that coil is done. If i were to get another coil with new wires (plugs were just done this summer, so shouldn't have to replaced, but will cheak for gap and/or damage) dose anyone thing that will work? Other then that I don't know. Getting sick of trying to fix this problem. For one, it's my old man's trucks (he dosne't understand anything about OBD and what it dose, so he gets me to fix it. lol), and mine runs great. Is there anything else I should look at?

 

[2000StreetRod]

shorted capacitor?

I still don't know what engine you have. If you have a V6 you may have a shorted radio noise capacitor at the ignition coil. You may want to try disconnecting the capacitor and see what happens.

 

[Exporer91]

4.0l v6 awd xlt

 

[Exporer91]

shorted radio noise capacitor? is that that little grey thing that is held by a little bracket thats gets attached to the coil with one of the four screw?

 

[2000StreetRod]

yes

yes