[landrovered]

John,

Don't take offense please but I put it in another context to make a point.

I have long been a student of EFI and its workings. I prefer EFI to carburetors for the simple fact that it gives me information. EFI codes can sometimes tell you exactly where the problem is like "misfire cylinder 6" but not all of the information is going to point directly to the problem at hand. It is just more data to consider while troubleshooting.

I had a V8 that kept throwing O2 sensor codes, I replaced the O2 sensor but the codes kept coming back. I was able to use other things that the engine was doing in order to finally conclude that the head gasket was leaking but not blown. The steam that was in the exhaust gases was causing the O2 sensor to react outside the parameters of set by the computer and thus it threw a code.

Many folks view the check engine light as something akin to the scarlet letter. They just want to get rid of it as quickly as possible. This is a mistake. This is what I was referring to in my analogy that seems to have gotten your goat.

In some cases a code can indicate that your car is running in a "safe mode" and actually function better with the CEL present than if you clear the code. MAF errors are one such situation. They can also indicate that the DME is running on different fuel curves as with secondary cat errors.

The point is, you are more likely to solve you problem more quickly and cheaper with as much info as possible than to ask for a bunch of guys who want to diagnose the most obscure exotic problem just to prove they are the top dog on the board.

So buy $129 code reader and you will get better info out of us than asking us to speculate as to what might have caused the code in the first place.