Cadillac: 1990 Deville, spark plug wires, number combinations

Question
QUESTION: I have a 1990 De ville that runs OK in the morning but at night when i drive it starts to sputter and when i press on the gas it just sputters then run fine, also when you cut on the air condition it makes it sputter. The check engine light is off.

ANSWER: When was the last time you replaced the spark plug wires as they tend to absorb moisture when they get old.

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QUESTION: I just had the plugs and wires replaced also a new distributer and roter. I took the car to the shop when the check engine light came on and they pulled up a couple of codes in the egr system they replaced a fuse and the car ran fine for a couple of weeks. I think it might be the map sensor, because at the light it starts to sputter a little and a couple of times it back fired sending black smoke from the rear. my check engine light came on today.

Answer
Check the computers for CODES via:

1. Ignition ON, Engine OFF.

2. Simultaneously push and hold the oFF and WARMER buttons for 3 seconds and release them.

3. Diagnostic CODES will start to appear as Letter/number combinations such as E34 or EE34 or any other letter number combination and will stop when you see .7.0

4. Turn ignition OFF.

5. Tell me EXACTLY what displays on the display panel before you see .7.0