Fuel Pump Problem and bad PCM.

On my 1993 Ford Explorer, the fuel pump would not cut out with in the normal 2-3 seconds upon first turning the key to the Run position.

After testing all components that I could think of, and all that the kind peeps on this site recommened, every test turned out normal.

Therefore, I went to the last item: the PCM. (I was hoping it was not the computer, because I am a retired guy on a fixed income. But, after opening the computer, I discovered a corroded lead to one of the small condensers.

But, in a way, I was happy, because I want the SUV to be reliable transportation, and solve the mystery of the on and off problem.

In hind sight, I should have opened and inspected the PCM first, as it is very simple to do. And, took every bit of ten minutes to remove and open the cover. The cover is held on by two small screws, allowing access to the circuit board for inspection.

The burnt/corroded component on the board jumped out at me immediately, much to my pleasure.

I am going to buy a new condenser tomorrow, if available, and solder a new one in place. The rest of the circuit board looks fine. (see pics)

If that does not work, I will have to get off a few bucks and buy a new PCM.

I'll keep forum posted on how it works out.

Thanks for listening.

opps sorry, can not post pictures. But. just spend ten minutes and check out your computer. You may be able to see obvious damage to it.


Mike in Virginia Beach

I had to put a new computer in mine and it was only like 120 bucks. I bought my explorer for 500 and it wouldn't start so after towing it home and installing a new starter, battery, and computer it was running again.

It's the capacitors that leak and cause the damage, not condensers.

The caps used in the PCM are pretty hard to get, you need to use the same rated caps or you risk even more serious problems. You can buy them online and solder them in, but usually if the cap has been leaking for awhile, the copper trace on the board is destroyed and you'll need to use a copper wire to take it's place.

Otherwise you can get new PCMs from Advance Auto, buy online and use a coupon and they are well under $100. Be sure to get the right one that matches the code on your original. Some stores have certain ones in stock, you might find one locally.

Think I will buy a new compter.

JTHale13 said:

I had to put a new computer in mine and it was only like 120 bucks. I bought my explorer for 500 and it wouldn't start so after towing it home and installing a new starter, battery, and computer it was running again.

Click to expand...

I got my Ford Explorer, 1993, 4.0 L,ovh, 4 x 4 for free. My son in law saw it in a garage sale for $500.00. He offered $100.00 and peeps took the offer.
Then he drove it to my have and gave it to me . What a great guy. I have rebuilt a couple of engines. And, they think I need something to do, now that I am retired. haha

I am pretty good on the mechanical side, but leave a lots to be desired on the electronic side.

However, I have no problem applying myself.

I just repaired the PCM for the price of a $2.00 capacitor. But, think I will do like you, and go ahead and buy on from Autozone for about same as you paid. I want the SUV to be reliable. So, think I will put some money in it.

Gota say, it is fun. and, I am enjoying these discussions, receiving help from so many great people, who are so kind as to take their time to help other who make repairs to their vehicles.

Take care and good luck on you Explorer.

Mike in Virginia Beach

Anime said:

It's the capacitors that leak and cause the damage, not condensers.

The caps used in the PCM are pretty hard to get, you need to use the same rated caps or you risk even more serious problems. You can buy them online and solder them in, but usually if the cap has been leaking for awhile, the copper trace on the board is destroyed and you'll need to use a copper wire to take it's place.

Otherwise you can get new PCMs from Advance Auto, buy online and use a coupon and they are well under $100. Be sure to get the right one that matches the code on your original. Some stores have certain ones in stock, you might find one locally.

Click to expand...

Hey, thanks for the info. I have a fixation on AutoZone, but If I can get a PCM for less than a hundred buck, I will. Think I will check it out tomorrow.

I misspelled calling a capacitor a condenser. Just typing too fact and not thinking.

When I opened the cover on the PCM I saw the one corroded lead. One lead was fine and one was either corroded of burnt. No other damage to the surrounding circuit. Good thing too. I knew how to tell correct polarity. lol

But, I was happy that it worked fine. Not sure how great my solder job is tho. Dont have the proper tools to repair the solder joint reliable.

But, the PCM is still 19 years old. So, think I will buy a new one. Not a bad investment to have reliable transportation.

Thanks for you help and replying to my dumb threads.


Mike in Virginia Beach

I got mine at auto zone. They even had it in stock our got it later that day I can't remember which but it was about 120 and I had to give them my old one.