18 months ago my 2000 Elantra, which was running just fine, failed to start one summer morning (engine turned over and over but there was no ignition). After a tow to the gararage the mechanic replaced the crank sensor, the ignition wires and spark plugs. Subsequently, it ran fine again but the check engine light came on repeatedly - intermittently at first, but now it is on most of the time.

A month ago, I experiencd the cold engine failure to start again. The wife said: "Did you check your air filter?" To placate her, I removed the air filter, which was only marginally dirty and still serviceable. To my surprise, the Elantra fired right up. To show my appreciation (to both wife and Elantra), I replaced the filter straight away.

The car started and ran fine until last week, when I experienced the third cold start problem. I opened the filter box, lifted the filter a bit and vwahla...she started again.

My mechanic's code reader has consistently discovered misfire codes. But the car never perceptively misfires. It runs fine and the gas mileage is consistently good. My mechanic suggested that the Hyundai dealer might have a Hyundai code reader that could more specifically identify the cause of both the check engine light and the cold start problem.

So, off to the Hyundai dealer who, for $100, told me what I already knew - codes for random misfires and misfires in cylinders 1, 2, and 4 were found once again. He also alleged that the cause of the misfires was a leaking valve cover gasket which had allowed oil to get into the plugs, the inside of the ignitaion wires and the pcv valve. It was also noted that the MAF sensor was coated in oil. He recommended new plugs, wires, and pcv valve all for a mere $410.

The plugs and wires have less than 10,000 miles so I was skeptical.

My regular mechanic then pulled the wires and plugs and showed me that there was no problematic oil. I doubted there would be because with 177k miles on the Elantra engine it still requires less than a quart of oil between changes (every 3,000 mile).

Our best hunch is that there is a short in the MAF sensor that intermittently causes the cold start problem. But what is causing the check engine light to go on and leave behind only the misfire codes? Could that be somehow related to the MAF issue also? Are we overlooking something?

Thanks to anyone who can shed some light on these vexing problems.