Engine Performance problem
1998 Cadillac SLS V8 Front Wheel Drive Automatic 65,000 miles
DTC P0103 current, P0101 current, P0303 pending, 2 weeks ago the car was stalling after 5 minutes driving. Check oil light and service engine soon light came on. Checked owners manual and it said that when it was 1 quart low the check oil light would come on, but it was 2 quarts low? I added 1 quart of Lucas engine oil stabilizer and one quart of mobil 7500 15w30. I read that the Northstar engine is very durable, but could driving around 1-2 quarts low hurt anything. Why didn't the check engine oil light come on after it was 1 quart low? After filling the oil just to the full line, I test drove the car to make sure it was ok. I drove it real hard because I wanted to make sure it drove just as well as it always had before. At first the tranny was sluggish. After a while the tranny was working smooth and the overdrive started working as usual. Car was driven normaly the next day for local trips. Then the next day after that I tried to start the car but the battery was down to 10 volts or less with no interior lights at all. I might have left the interior light on overnight, but the owners manual said that there is an automatic shut off after 10 minutes for the interior light in case it's left on. I tried to charge the battery with 10 amps at the proper + and - connectors under the hood but the battery chargers needle would go haywire (as soon as I connected the battery chargers - connector to the - bolt terminal ) and all the way to the right as if the terminals were connected backwards? But they weren't. It ook a long time to undo the situation by making a better contact at the - bolt terminal and finally the battery chargers guage needle slowly went towards the middle of its guage reading and started to charge the system. After 30-45 minutes of charging the car was finally able to start. I never figured out how the battery got so discharged and it hasn't happened again. The service engine light was still on from the 2 days before. The car was driven normaly just some small trips here and there for the next 2 days. Then the mil light went out and has not returned. I went out and got an dtc code only scanner. It now shows the codes listed above. I noticed that the mpg reading on the dash info center was way under 10 mpg, the car is not idling as smooth as it used to, and that the exhaust is not as clean as it used to be. The car starts up ok, is idling sort of ok, has full power at all rpms. You can hear or feel that #3 cylinder missing a samall amount, it affects the smooth idle. What is probably setting off the dtc P0103 and P0101? I have never worked on a late model car and would like to replace or repair the part or parts with the least amount of diagnostic testing. There is so much testing with the mass air flow circuit. Since it's a high reading does that point to something else causing that reading or could the maf sensor need cleaning or replacing? Could the P0303 condition be causing the P0103 and P0101 to set. If I check spark plug 3 do I have to torque it when I put it back. Can I replace just that 1 plug. I've never taken the plastic engine cover off before. Is it easy to get to the mass air flow sensor after the engine cover is off? Which is the correct spray cleaner. Is a q-tip with alcohol also ok to clean it. Does it need cleaning with a high reading or only when their is a low reading. I read about water getting in somewhere or vacuum leaks causing this problem. Could all of this be from the battery losing it's power and the PCM losing all of it's settings? Will this fix itself after the PCM resets itself after driving without any repairs? The owner of the car took it to an auto mechanic to ask about a needed inspection. He saw the engine light and ran the code scanner and was saying a few hundred for this and a few hundred for that, and more. We can't afford the mechanics charges now. We don't want to pay to replace parts that can be cleaned, adjusted, or repaired. I read somewhere about a 2001 Chevy and it was recommended to work on the P0303 first before working on the P0101, P0103. What about testing that all the connectors are on tight and have clean contacts? Are there any connectors that would cause a problem if they were disconnected to check them with the car on or off affecting the PCM? Can I get to the bottom of this problem without using a scantool such as elm 327, volt and ohm meters, air pressure testers, oscilscope, etc, etc. I have a digtial multi meter. I read somewhere that an analog meter or osciliscope might be needed for some of the MAF tests. This is too much for me because I can't get into a complicated time consuming project in a small driveway. Can I get somewhere with fixing this problem without all of the scanning, volt, ohm, etc. Tests.
have the same problem?
Friday, September 19th, 2008 AT 9:38 PM