The Chrysler Minivan Fan Club Forums banner
1 - 10 of 10 Posts

·
Registered
Joined
·
97 Posts
Discussion Starter · #1 ·
I had gotten a P0456 code ("minor evap leak") and took it to a shop. No more than 5 or 10 minutes after the mechanic started looking at it, I was told it needed a new cannister purge valve.

So they replaced the cannister purge valve, and I paid them for the part and labor, along with a $125 diagnostic fee. They also replaced the gas cap.

Then, about a week later, the P0456 code came back.

So now I'm wondering if the mechanic even did a smoke test, or if he just figured that it's usually the cannister purge valve or the gas cap when there's a minor evap leak, so just went with that, and charged me for the diagnostic.

What do you think? Is it possible that he did a smoke test and diagnosed the problem in 10 minutes?

2003 Dodge Caravan SE
 

·
Registered
Joined
·
440 Posts
A smoke test is not used to diagnose a purge valve. It's used to find leaks in the system. There are some quick tests that can be performed on the purge valve and perhaps the mechanic performed one of these tests and the valve failed. I doubt a smoke test was performed. It takes at least 10 minutes to begin to fill the system with smoke. The purge valve is by far the most commonly failed part in the evap system. $125 strikes me as a little high for 10 minutes of diagnosis. You could take the car back and state you have paid full price for a diagnosis and something was missed so the rest of the diagnosis should continue at no charge. I wish you luck but the shop can wiggle out of anything.
 

·
Registered
Joined
·
97 Posts
Discussion Starter · #3 ·
A smoke test is not used to diagnose a purge valve. It's used to find leaks in the system. There are some quick tests that can be performed on the purge valve and perhaps the mechanic performed one of these tests and the valve failed. I doubt a smoke test was performed. It takes at least 10 minutes to begin to fill the system with smoke. The purge valve is by far the most commonly failed part in the evap system. $125 strikes me as a little high for 10 minutes of diagnosis. You could take the car back and state you have paid full price for a diagnosis and something was missed so the rest of the diagnosis should continue at no charge. I wish you luck but the shop can wiggle out of anything.
Thanks! That's very good to know that he might have just tested the purge valve during that 10 minutes, rather than just "guessing" that it was probably the purge value. So at least I know he probably did something. So that's better.

Still, another shop I had talked to before this one, when I told them I had a small evap leak code said they'd need to do a smoke test (and would charge me $120 for it). So I just assumed that was standard procedure with a P0456 code, that you do a smoke test to look for an evap leak.

In any case, I did bring it back to them yesterday on the basis of what you said -- that I paid for the diagnostic, and apparently they missed something. 24 hours later I called to check on it, and I was told "he's just now taking a look at it." Didn't hear back from them after that today.

So I'm not very optimistic that anything's going to get done. I'll call them tomorrow and see what's going on. But I'm not optimistic.
 

·
Registered
Joined
·
406 Posts
The typical diagnostic fee is 1 hour of labor. I would expect the diagnostic fee to be applied to the labor needed to replace any parts though. So, if it takes 1 hour to replace the canister I would expect $125 + the canister price and not any additional labor charge.
 

·
Registered
Joined
·
97 Posts
Discussion Starter · #5 ·
The typical diagnostic fee is 1 hour of labor. I would expect the diagnostic fee to be applied to the labor needed to replace any parts though. So, if it takes 1 hour to replace the canister I would expect $125 + the canister price and not any additional labor charge.
Yeah, I've seen that before at shops. No diagnostic fee if you have the work done. This shop, what they told me at the start, was that if it was 4 or more hours of labor, they'd waive the diagnostic fee.

Just one more reason to never use this shop again. LOL
 

·
Registered
Joined
·
312 Posts
The typical diagnostic fee is 1 hour of labor. I would expect the diagnostic fee to be applied to the labor needed to replace any parts though. So, if it takes 1 hour to replace the canister I would expect $125 + the canister price and not any additional labor charge.
Smart shop owners who want to keep top-notch employees and have satisfied customers don’t give away diagnostic time. Accurate diagnosis is far more difficult than parts changing, and requires much more knowledge and expensive equipment. If anything, diagnostic time should be more per hour because they’re not getting parts profit on diagnostic time.

I know some shops do give it away, but they’re shooting themselves in the foot.
 

·
Registered
Joined
·
282 Posts
So now I'm wondering if the mechanic even did a smoke test
No.
or if he just figured that it's usually the cannister purge valve or the gas cap when there's a minor evap leak, so just went with that
Yes.

Saw the same thing at play the last time I went into a parts store (think it was Advance); the "professional" behind the counter assured a guy he needed a purge valve, vapor canister, and gas cap to cure his P0456. The parts cost more than the poor schmuck's van was probably worth.

I had a very elusive P0456 about 8 years ago on my 2005. My wife rented a smoke machine from Party City for under 10 bucks. Took about 20 minutes to find my leak, which was a very small weep from the fuel pump mounting O-ring. Changed the fuel pump and that was that.
 
  • Like
Reactions: Road Ripper

·
Registered
Joined
·
97 Posts
Discussion Starter · #8 ·
Saw the same thing at play the last time I went into a parts store (think it was Advance); the "professional" behind the counter assured a guy he needed a purge valve, vapor canister, and gas cap to cure his P0456. The parts cost more than the poor schmuck's van was probably worth.
At least the guy at the parts store didn't charge $125 for the advice! LOL

I had a very elusive P0456 about 8 years ago on my 2005. My wife rented a smoke machine from Party City for under 10 bucks. Took about 20 minutes to find my leak, which was a very small weep from the fuel pump mounting O-ring. Changed the fuel pump and that was that.
That was very clever to rent a smoke machine from a party store!

And that's interesting about the fuel pump. I've been having fuel pump problems for a few years (makes a high-pitched whining sound when the tank is less than half full and it's very hot out and the car sits idling for a few minutes). So maybe mine is the fuel pump as well.
 

·
Registered
Joined
·
282 Posts
At least the guy at the parts store didn't charge $125 for the advice! LOL



That was very clever to rent a smoke machine from a party store!

And that's interesting about the fuel pump. I've been having fuel pump problems for a few years (makes a high-pitched whining sound when the tank is less than half full and it's very hot out and the car sits idling for a few minutes). So maybe mine is the fuel pump as well.
Take a peep underneath on the passenger's side...mine actually had a slight grimy residue trail from the O-ring. One of those things I now know to look for.
 
  • Like
Reactions: Road Ripper
1 - 10 of 10 Posts
Top