Cadillac Repair: engine sputtering, code checker, exhaust pipes

Question
QUESTION: My 1992 cad seville 4.9L, brought new with only 52,000 miles on it has suddenly started sputtering and spitting.  Seems to start running on fewer cylinders and sometimes just shuts off but also will clear up too.  There seems to be a little black soot coming from exhaust pipes. Somedays it runs fine for a while but eventually will start doing this.  I replaced the fuel and air filters and the ign module but that didn't help anything.  If i let the car just run in the driveway it will speed up and slow down (rpm) and then it can just smooth out and run fine for a while.  The check engine light will come on only if left to run for say 20 min or so. I have a code checker which works on all GM but Cadilacs so can't help there. Any help would be appreciated.

ANSWER: To get the CODES:

1. Turn ignition ON. Do NOT start engine.

2. Simultaneously push and hold the OFF and WARMER (^) buttons on your climate control panel for 3 seconds and release them.

3. Codes will appear in the form of LETTERS & NUMBERS followed by the word HISTORY or CURRENT for each codes that displays.

4. The display will stop at ECM?

5. Tell me exactly what displays as if you were video taping the display.

6. Turn ignition OFF.

---------- FOLLOW-UP ----------

QUESTION: codes are in order and are all history except A048:
E026
E032
E052
E062
E071
E098

I033
I034
I037

A048 CURRENT
A037

R033

ECM?

If this helps please advise what I should.

Thanks, Robert

ANSWER: A048 means that you are low on freon in the A/C system.

Take the vehicle to any Autozone parts store and ask them to ERASE the codes for you with their scanner or if you know how to erase them via the climate control panel, Do so.

Disconnecting the battery will NOT erase the codes.

---------- FOLLOW-UP ----------

QUESTION: I've cleared all the codes and the A048 reset we know that's just low freon and code E062 has reset in history.
I've noticed that the data info center on dash starts to blink just before the engine shuts off. Could this be a bad connection at the PCM or any other help would be appreciated.  Also if you could tell me exactly where this PCM is located/

Thanks, Robert

Answer
E062 = Cruise Control vacuum solenoid problem.

This is caused by an intermittent fault possibly in the:

Brake switch.

Cruise switch

Cruise servo.

Cruise selector switch.

PCM (computer).

An intermittent wire connection in any of the above.


There are test procedures that you can do but with intermittents, It may NOT show up unless the fault is present at the time.

Do you have ANY cruise control problems ?.

If you would like  pictures and test procedures to try and narrow this intermittent fault down, You can obtain them by e-mailing: onlineautohelp@msn.com