Cadillac Repair/1988 Cadillac Fleetwood
A repair shop recently worked on the car, a 4.5 liter FWD, when it just stopped on the road. They replaced the alternator and the battery. Three weeks later the car did the same thing, and the same repair shop replaced the distributor, dis. cap, rotor, and ignition coil. It was transported back to the shop the next day when it sounded more like a diesel. The shop had not used a timing light to adjust the distributor / timing.
After driving with no problems for about 3 weeks, it started running rough. SERVICE NOW appeared on the information gauge. I looked for a distributor hold-down bolt being loose, but saw nothing. I did see a 1-inch tubing not connected behind the cover over the distributor - where a carburetor was on older cars. I replaced that.
Then I unscrewed the fuel cap, heard a long hiss, and replaced the fuel cap. When I started the car, the SERVICE NOW warning had gone. Figuring the 14-year-old fuel cap was probably defective, I replaced it with a new fuel cap. It started and drove normally.
Using the method in a car manual, I found one code, E32. I cleared the code using the method described.
Is it possible that the code had not been cleared by the shop, and the fuel cap was causing the irregular running problem?
Or could the loose / disconnected hose have caused the code E32, Open Manifold Absolute Pressure sensor (MAP) to be set?
Maybe too much pressure created in the fuel tank by the old cap?
It's running fine today. My wife drove it to her job. I'll check the code again when she comes home.
You may not care for my thoughts here, but I would have never let the mechanic or shop ever touched the car when told it needed an alternator and battery. That tells me right there there is no knowledge. It's not both,but one or the other. If the alternator fails, the charge light will illuminate. The service engine not soon,but now will come on. The engine will eventually stall when the battery discharges to 10 volts or under. That does not mean the battery needs to be replaced,but if the alternator is charging battery voltage won't go below 13.2 volts.
These people sound like dealer techs also known as parts changers whether the parts need changing or not!
In reality, explaining as to the actions you took with the gas cap, you sounded more knowledgeable than these people you entrusted to work on your car.
Service engine soybeans the computer system is in open loop and it not operating at peak performance. This is an emission issue and engine will run. Sometimes not well, but will run.
Service engine is serious! It means that if not services immediately, the engine will stall. As I said, if the alternator is not charging, that is one example that if not services immediately,it's going to quit running.
A bad has cap should only be a service engine soon and changing the cap should not have turned off the service engine now light.
I am concerned you are dealing with an intermittent problem which is exacerbated by click and clack changing parts arbitrarily on the car.
It is hard for me to really address this problem you have with the vehicle because I am not with the car to see the symptoms.
What is suspicious to me is that the first time it was diagnosed and repaired, it should not have had completely different repairs 3 weeks later for the same symptom of not running. And more problems weeks later?
As I said, I am wary of the repairs that have been applied to your car.
Think about this: maybe that hose was your problem all along and you wasted a boat load of money.
If the tank is 1/2 tank or below, it is common to remove the gas cap and hear a hiss.
I doubt if they ever cleared the codes!
Do one of 2 things. Either take the vehicle to competent techs, or buy yourself a factory service manual for the car and fix yourself. You would be surprised what you could diagnose and repair with the factory manual. Cost on eBay is about $100.00, but I bet you paid more than that to have the same complaint fixed twice!
Good luck and let me know if you have more issues.