P0420. MAF?

[(K)]

Here's some background: A few weeks ago I was cruising at about 65 MPH on the highway and my CEL came on, the car didn't act funny and I didn't notice any considerable change in my fuel mileage. So I took the car to autozone and pulled two codes (both codes were the exact same):

1 of 2
P0420 Catalyst System Efficiency Below Threshold (Bank #1)

2 of 2
P0420 Catalyst System Efficiency Below Threshold (Bank #1)

I'm thinking it's either the cat or the O2. Either way it's GOT to be covered by warranty for emissions and I wouldn't have to pay any fees since the warranty covers fees. So I brought it to the dealership yesterday.

They called me back a few minutes ago with this:

Dealership: "A hose was loose on your MAF, my mechanic plugged it back in"

$90.00 Diagnostic fee. WTF!

Me: "no way! He plugged a hose back in and you guys charge me $90?"

Dealership: "Well the mechanic had to pull the code and trace the problem as well as actually do the work".

DO THE WORK?!! I went to autozone to pull the code MYSELF, it takes 5 minutes. You plug it into your OBDII and turn the car on, the code reader does the rest. This is all had for free BTW.

If any actual "work" was done, it was to lift the car to check the problem area and then open the car door to get to the hood latch release. That's it. No tools were used (outside of the reader) and no actual wrenching was performed...

Someone please justify what they said about a hose on the MAF being able to trip an O2 or cat code. That way I don't go in there hootin and hollerin my head off.

This is for a 2002 4 cylinder BTW, the drive by wire and all that good stuff.

[Sentinel]

If this repair was/is under warranty for emissions then the diagnostic charge should be waived.

If it is NOT under warranty: then that is EXACTLY what the charge is for. While those of us able to do the work understand that it was not any work at all to do the repair, think that they had to do the same paperwork, scheduling and all the other crap that is required, even if it was simply a fuse replacement. How often do you think little old ladies go to the shop for dinky fuse replacement / loose hose tightening etc...

You might count yourself lucky that they didn't charge you a half hour labor for the 20 seconds of work they did.

[(K)]

OK I got it resolved...

They should have been more clear. I ended up talking with a different service advisor than the one I was speaking with over the phone. Apparently they charged the diagnostic fee for something completely unrelated. I originally bought the car in for the CEL but I also had another issue with the interior lights going on and off. The CEL was done WITHOUT the diagnostic charge, the interior lights were what they charged the diagnostic fee for.

Makes sense since bulbs are not covered by warranty. The advisor that I spoke with over the phone might have read the work sheet wrong. I do that at times too.

eh, long story short; I'm glad I didn't go in there like a madman and make myself look like an idiot. Not that I would have anyway, I don't have the personality to talk to people like that anyway...sucks.

On a side note, I understand WHY there's diagnostic fees; when there's actual diagnosis being done. Where I work, small things like that are overlooked and rarely does any place I've been to ever charge for it. How I look at it is: If a part has to be replaced or there was excessive work performed just to tighten a bolt/hose etc. Then there's a fee.

Still haven't figured out how that code and the hose are related though...

[Jackass-Jeff]

The hose is part of the emissions system. It becomes loose sometimes when you do your own oil change, some outside sources (jiffy) loves to unplug it and sometimes forget to put it back in.

Lots of people assume the CEL is "This part is broken, fix me", but it's not. The CEL is for general diagnostics and helping determine where the problem is. It doesn't necessarily say "Oh noz, my hose is not plugged in". So sometimes strange code sets are put out. The same code is triggered if the gas cap is left loose.

[Dawgz]

That 90 dollar fee is okay for this job, since u took it in and they did all the work, what were u expecting form a dealership? A bill for 20-40 bux?