1998 cadillac seville sls 92k--
Ok I have a real brain teaser here. About a year ago, the car would just die at a stoplight or when accelerating. I took it to the dealer, and they finally determined that it was the fuel pump. So about a thousand dollars later, they fixed it. The next day, it drove fine, but would not start after being parked all night. Took it back in and they did something to it and it worked ok. Made it through the summer, but toward the end of summer, the car now just dies altogether when going down the freeway at 75 mph (scary). Anyway, the only code I get is P0603 and a couple of irrelevant ones for the bose system. Could it be the PCM or would it be in the wiring to the fuel pump. I have a suspicion that the fuel pump wasn't really bad, maybe the wiring to it or the PCM could be malfuntioning when under extreme heat. It gets really hot here in the summer. In all cases of stall, it will restart after the motor cools down, but if it is really hot outside, the stalling will happen again when the motor gets up to operating temp or a little above (halfway on the guage). Any info would be greatly appreciated.