1990 Mercury Marquis PCM replaced

GRANMARQ90

MEMBER
1990 MERCURY MARQUIS
V8
2WD
AUTOMATIC
204,589 MILES

When I had my car overhauled, the shop burned my computer(PCM). They replaced it with a similar type. But the car is not functioning 100%.

1. The car needs two trys to start.
2. Once running, high rpm, then settle down idling. Sometimes it will idle down 'till engine is dead.
3. Try the car forward or reverse(if still running), it stalls.
A code scanner always point to the MAP sensor as being out of range. I have a Chilton Repair Manual for my (FORD) Grand Marquis 1990. A check of the old and new MAP sensors give me an output well within the required range.

Now where can I have the PCM re-progammed/re-flashed?

Or can I purchase a new one and provide them with the calibration code, VIN#, Mileage, etc?

5 Replies

RACEFAN966

MECHANIC
5,029 POSTS

Ok you say they burn out your PCM and replaced it with a similar type? What is a similar type? The numbers have to match as does the calibration code. If not no matter what you do it will never run as it should. Do you have the old one they burned up to compare to the one in there now so you can check the numbers? Ford computer have a sticker on them that gives the calibration number it is like a 3C6 or? This also determines which engine it made to run with too. Get back to me with what you can.

SPONSORED LINKS

Was this

answer

helpful?

Yes

No

Tuesday, October 6th, 2009 AT 9:57 AM

GRANMARQ90

MEMBER
3 POSTS

Ok, first off = Calibration Code on Door Jamb 8-22G-R00. Other number, E8AE-6E061-AEK.

VIN# - 2MECM75F3LX627254 (JUST IN-CASE)

Orig (Burned) PCM - F0SF-12A650-DA

Installed PCM - F0SF-12A650-DB

Was this

answer

helpful?

Yes

No

Wednesday, October 7th, 2009 AT 3:58 AM

RACEFAN966

MECHANIC
5,029 POSTS

Ok it looks like the new one may have come out of a truck which is different then the car. The car has a different injection and different timing settings and more. The one problem I see is the old computer I can see the large number that is the code I am looking for. The new one has the U0L1 the onther don't. It has U0L there is no 1 there for they are not programmed the same. That code is amost more important then the Ford part number.

Was this

answer

helpful?

Yes

No

Wednesday, October 7th, 2009 AT 10:15 AM

GRANMARQ90

MEMBER
3 POSTS

Still, my question hangs.

WHERE can I BUY a NEW PCM, and have the PCM programmed for my car based on the calibration code?

Was this

answer

helpful?

Yes

No

Wednesday, October 7th, 2009 AT 2:14 PM

RACEFAN966

MECHANIC
5,029 POSTS

Well what we did figure out is that the PCM is not correct. Now what you can do is go to you local parts store with the original PCM from the car and buy a remanufactured one or if one isn't available for your car then have them send it in and have the original one remanufactured. I would also ask that the shop that fried it pay for it. I don't know what parts stores you have in your town but I have done this with the Napa in my town with PCM's that are no longer available. Let me know how it goes.