The story started sometime earlier, about two years ago… apparently I changed the fuel pump on the son’s car back then. The owner decided his gas mileage had dropped considerably. To the point that he was concerned and very upset that there was obviously something that I had done wrong to cause it. I guess it had been grating on him for two years.
He insisted that the new fuel pump was to blame because he always tracked his mileage by way of his trip odometer. Before the new fuel pump he would get close to 400 miles per tank. His accuracy was noted on his little log book and showed how much gas he would refill his tank with. It was always around 23 gallons and never a drop more than 23 gallons. But now his tank was holding 26 gallons.
His question to me was, “So, where is the other three gallons going?” I had to laugh. I’ve changed a lot of fuel pumps but I never have had anyone come in and tell me that the tank suddenly holds more fuel than before.
My guess was that his original gas tank sending unit was probably inaccurate and that was the discrepancy.
“I’m pretty sure your gas tank hasn’t increased in volume since the fuel pump has been changed. I would imagine you’re probably mistaken as to how much your tank actually holds,” I told him as I reached for my coffee.
Nope, he wasn’t buying that answer. He knew how much his gas tank held and he knew I was the cause of his three missing gallons. What he wanted was for me to find out why his gas mileage has decreased so much.
I tried to explain it to him, but he was very, very sure he was correct and I wasn’t listening to what he was saying. He was getting quite loud and belligerent over the whole matter. Poor old dad just sat there with a smirk on his face. I kinda figured dad had already had enough of his boy’s attitude and figured old Gonzo was going to straighten him out. (This is going to take a lot more coffee…)
The aggravated son then began to tell me how good a mechanic he was, because he had rebuilt a few motors in the past so he knew what he was doing under a hood. (Note: putting parts together does not a mechanic make. That’s solving puzzles and it doesn’t need a mechanic.)
Then he added to his story with the usual… “I went to one of those parts stores that will read codes for you. They said the reason for the check engine light was because of a bad gas cap.”
He was grasping at possible reasons why his gas mileage had dropped so much.
What gets me is how something as important as the service light isn’t brought up into the conversation until after you have told me how good a tech you are and that you have already made the decision that I was to blame. (I’m going to need more coffee.)
So at this point, we have a service light on, we have a supposed loss of fuel economy, and I’m sure there is more… there is always more… I had to ask, “Anything else?”
On occasions the ABS light comes on. He had that checked too. This time he consulted the ever faithful Internet. He tells me in a loud forceful voice, as if I couldn’t hear anything he was saying, “That always means it’s time to rebuild the ABS controller.”
Oh yeah, I do that every day. I take the controllers apart and remove the epoxy sealer over the circuit boards and remove the affected components on the board and then reseal the whole thing back together. All this before a full cup of coffee? It’s really too early to absorb this kind of dazzling technical information.
After dad and son dropped the truck off, I went straight to the glove box. I checked the owner’s manual as to how much capacity the fuel tank held. It had it in big bold letters: 26 gallon capacity, not the 23 that he had logged so meticulously.
While I had the truck in the shop I checked the tune-up parts and the filters. All looked great. The next thing was to tackle the check engine light. Yes, there was a code. A code that might lower gas mileage? Sort of, but not by three gallons, that’s more than 11%, right?
It was the evap solenoid valve code, p0449. After doing the test on the valve it turned out the valve wasn’t responding to the PCM commands. A new evap solenoid valve solved the problem. As far as the ABS? Nothing; not a thing; no codes; no history codes, and the system was working normally.
A drive test showed no problems and I gave him the benefit of the doubt that he may have an intermittent ABS controller problem… however when I gave him the option of leaving it alone or changing it… he left it alone.
After all the phone calls were made and arrived to pick up his truck there was never any mention of the alleged missing three gallons or the fact that it was merely the original fuel sender that was reading improperly all this time. Or the fact that the loose gas cap had nothing to do with the service light this time around.
I guess when you’re wrong you don’t have to admit it. That is, when you’re the customer. But you can be darn sure if the mechanic is wrong, everyone will know about it, and somebody is going to have to apologize.
I apologize for being the mechanic in this story and I guess I should apologize for one more thing… Writing in BIG letters on his invoice… YOUR TANK HOLDS 26 GALLONS! !