Engine Light stays on on 2000 Mazda MPV

Engine Light on Dash Panel. The first time it came on was a couple of years ago and it was a loose gas cap. I tightened in til I heard a click and it corrected it for a couple of years..then, it began to do it about every six months. I put a little vaseline on the rubber ring on the gas cap and that worked for a couple of years. Then, someone told me to disconnect and reconnect the battery negative cable.. that worked for a couple of months, then, I bought a new gas cap and installed it. A few months later the engine light came on again. Presently, I can wipe clean the rubber ring on the gas cap and tighten to a click or two, then, remove and reinstall the negative battery cable and that makes the light go out. However, it never lasts more than 3 or 4 start ups and when I start the engine, the engine light will not go out. I can make it go out by repeating the process but it doesn't last more than just a few start ups and bingo it won't go out again. Anyone have the answer...Oooh, I checked the fuse and pulled in out and reinstalled...no help there. Bob Reese

by in Santee, CA on April 08, 2010
2 answers
ANSWER by on April 08, 2010
The check engine can come on for hundreds of reasons, not just a loose or defective fuel cap see this article http://repairpal.com/check-engine-light have your code(s) retrieved by a skilled Tech
ANSWER by on April 09, 2010
everytime you pull the cable, you reset all memory presets. not a good thing. the next time your light comes on. take it to a shop and let them look at it. they can get what is called freeze frame data that will give them crutial info about what occured at the time of the failure. when you erase the code, you erase freeze frame making it difficult to diag correctly. Roy
Related Items:
This started w/just a flicker of oil light at idle then it would stay on till 900, now it stay's thru 1600. No knocking so far. I had the oil pan removed and cleaned the oil pump suction screen
This started after I filled up the gas tank. I have changed spark plugs and coil packs, still does it. Engine light stays on.
Seeking help with this issue, when i start engine the load leveler operates and raises the rear to normal height as it must have a leak in the lines or shocks, I have a battery monitor plugged into...