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08 F250, 33K miles. Customer was in for some other concerns and mentioned the over boost thing to me as a side note. He claims he was at another dealer a few months ago and they reprogrammed his PCM. Ever since he claims the truck is over-boosting. While towing approximately 15k pounds, he says the boost gauge is maxed out, and when he lets off it flutters pretty hard. He claims it never did that before the reprogram...He is coming back next week and I'll dig in a little more, but he already asked me the golden question, "What causes that? Why is it doing it?" and wanted his answers immediately.

 

As of right now I have not done any diagnosis with IDS. He seems pretty bent on the fact that updating the PCM caused this issue. I told him I suspected VGT vanes, or faulty EBP sensor, things along those lines. Unloaded, driving it WOT I saw close to 34 psi, based on the gauge display. That did seem high to me, plus this truck moves along considerably better than an exact duplicate I just drove the other week. But is 40 psi while towing really that far fetched? How about the update causing turbo issues like this? Wondering what you guys have seen in regards to this.

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I could hit 40psi on a certain stretch of road with my truck stone stock, without even having it fully laid out.

 

Towing across Canada with a 4500lb car on a 2000lb trailer, plus about another 2500lbs of shit (Ask Jim - he saw it LOL) I was 38-41psi all the time up hills.

 

Check it for codes if there isn't an over boost code, I wouldn't lose a whole lot of sleep over it, in my opinion.

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That wasn't a car - that was a Chevy Posted Image

 

For the OPs boost issue... I'd be looking at MGP or whatever they call it now. The cluster might be an issue on it's own. If there was a concern with overboost (especially "gauge pegged" overboost)- don't we think that there might be a code in memory?

 

Customers tend to speak in code... and they like to throw technical sounding terms around (especially the ones they got off the internet).

 

My car pulls to the left means the steering wheel is off centre. My truck "hesitates" on the highway.... 'scuse me? I turn the key and it wont "crank" (which may or may not mean it wont turn over or it turns over but wont start).

 

Gawd I'm turning into a cranky old phuque.

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"Customer diagnosis"

 

Had customer come in and tell me to change glow plugs.

 

Put 8 glow plugs in the truck and punted it.

 

"Uhh, my truck doesn't start"

 

Hey, you wanted the glow plugs changed... Didn't mention anything for a no start. It started for me.

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"Customer diagnosis"

 

 

This has been going on as long as I've been in the business. There's been many times I have changed what the customer wants changed, all the while staring at broken shit. "Hmmm, wonder why he don't want to fix that?".

 

Even before the interweb.... we would see all manner of remedies. Guys asking for a manual choke kit was one of my favourites... granted, the number of mechanics that could actually fix an automatic choke was small, it was more a case of not wanting to pay beans and wiener prices for prime rib.

 

Something we have probably all seen in this brave new world is a customer with someone elses diag/estimate in hand wanting us to perform the work - as if by some magical/mystical process, having a good tech perform bullshit work was going to make everything OK.

 

"Mister, I can fix your car - but I don't want to marry it".

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Something we have probably all seen in this brave new world is a customer with someone elses diag/estimate in hand wanting us to perform the work - as if by some magical/mystical process, having a good tech perform bullshit work was going to make everything OK.

 

In those kinds of situations it is usually best to ask why "someone else" or "my mechanic" isn't the one fixing it.
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In those kinds of situations it is usually best to ask why "someone else" or "my mechanic" isn't the one fixing it.

Actually, it rarely get's to asking that. The question is "do you want me to fix it or not?". The method is "my way". If I am to be wrong, it will be by MY mistake and not someone elses. I'm a self-centered prick. I like it when people remember me - and I really don't care what they remember me for - as long as it's honesty.

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"I had all my injectors changed and I still have all these injector circuit codes!"

 

My favorite of all time.

Oh don't get me started on THAT one. I must've had at least three of those in just the last one and a half month alone.
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Haha, thanks for the responses. This guy is DEFINITELY one of those "I already have it figured out because I read a couple forums about it" type.

 

I will post back my findings, if any.

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"Customer diagnosis"

 

Had customer come in and tell me to change glow plugs.

 

Put 8 glow plugs in the truck and punted it.

 

"Uhh, my truck doesn't start"

 

Hey, you wanted the glow plugs changed... Didn't mention anything for a no start. It started for me.

I love that one. I will typically ask why he wants the glow plugs changed. You do need to tread lightly when asking as to not look like a total dick to the customer. I will ask if they have been having any other issues with the truck that they might want us to look at while we are in there. 95% of the time the response is "yeah its been hard starting or no start when cold which is why I want to replace glow plugs" From there I can convince them of a proper diagnosis as to not waste their money throwing parts at it

 

 

The internet is a very powerful tool but I really hate these customers that read a couple forums and now they think they are pros Posted Image

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The internet is a very powerful tool but I really hate these customers that read a couple forums and now they think they are pros Posted Image

It's not JUST the vehicle owners. Am working part time at a one man shop. He's been a mechanic for 27 years. Today we were diag'ing a no-start Onan generator in a Fleetwood motorhome. First thing I noticed was a lack of battery voltage when pressing the start button. Solenoid would buzz. 7.9V just won't cut it. Checked voltage at coach batteries. 8.9V. Started coach up and voltage was 14.5 at batteries, 13.6 at starter terminal.

 

Needs a starter, right?

 

He kept asking me if I jumped across the solenoid. Could NOT grasp that the 13.6V was AFTER the solenoid. The funny thing is he has an S-10 he built that has been on Pinks-All-Out.

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