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Hi all, i just got my first "Failure" got a customer in for a basic fuel change.. Tuner by another company did the ethanol tune on it..

Customer wanted 102 octane fuel and he got the car down there

. Did a first pull with E85 and reached 214crank hp on my dyno..

First warning sign i should've reached to was when he stated that it's a little low on power and the other company had 272 horsepower out of a brone stock M54b25 with bmw m54b30 camshafts...

I started changing out the fuel since the logs looked great.

After flushing the fuel system i started with changing the global settings in EMU and it started up but VE table seemed way of.

Ve of 5% @ idle

Checked and found a global fuel trim set to 30% on all injectors.

Fixed that and started doing some steady state and fixing the ignition and fueling tables.

After a few hours on the dyno i felt good and got over to acc enrichment and lambda guard, EGO feedback and everything was good and customer took the car back. The day after he called sad the car died every time he accelerated ä. I got in the car and drive down to him and started looking at some logs and found nothing out of the ordinary lambda, trims etc all seemed good. So we decided that he should bring the car down to me and i will go over it.

However today i heard from a third party that he was not a happy customer and that i did i shitjob and should not tune a car ever again ( apparently from the first company).

I have tried calling the customer but he does not respond or call back.

I feel miserable and my confidence took a big hit.

Now i can never find out and learn from what i missed or become better, reputation destroyed by one miserable customer :(

Did you road test the car before handing it back to the customer? I always got the owner to take the car for a drive with me in the passenger seat with the laptop connected to validate the changes and make sure that the drive-ability was still there.

Was the temperature quite different the next day to when you tuned it?

Why did he got back to the first tuner?

I expect everyone has had a problem with an unsatisfied client - often because they have unrealistic expectations.

In this case there are several questions -

Why did the 'client' go to you rather than stay with the other company, a company he seems to be happy with.

What evidence did he have of the claimed "272 hp", what was it supposed to have been achieved on , and what correction factors were used - there's a reason dyno' numbers shouldn't be relied on, as the "number" depends on many factors that are usually different between different machines and operators. That your base line was much lower, 214 hp, suggests the previous tuner, or the client, is lying - especially as the '25 is rated a little over 200hp, and the '30 around 228hp - your numbers, for the engine you describe, would seem to be pretty much dead on the money!

Why didn't you test it on the road yourself or, preferably, do a road test with the client?

Why did the client refuse to allow you to verify the claimed power loss, and why didn't he allow you to double check your work?

Why did the client go directly back to the previous "tuner" and, apparently, complain to them?

Call me cynical, because I am, but even so I'd be rather suspicious that it was a "set up" to discredit you.

A 30% trim baked into the tune, that's pretty crappy. I use the fuel trim to get an engine started, and then remove it once I have applied that percentage to the overall base numbers in the VE table. I wouldn't let a car out the door with a trim like that in place.

That sucks man. I think everyone running their own business has some kind of similar story. I know I do

Many tuners won't 'touch up' someone else's work, they just start over for reasons exactly like that. 30% fuel trim isn't something you'd think to look for especially if the car runs ok, but a setting like that baked in is a problem. I also recommend street driving the car and keeping it overnight until cold start is good.

The first jobs you do won't make you money but will teach you a lot.

There's an aspect of working on cars like this that's tough because I find a lot of people think they know more then they do, and they feel a need to tell anybody in ear shot. Eventually you'll see the signs of a customer you don't want to work with, but you'll always be surprised every now and then. One needs to strike a balance of doing good work, refusing bad jobs or clients, all while making enough money to survive.

Thing to avoid is getting into heated arguments about what went wrong, let the data show you and if they won't allow you to see the data then that's a them problem. I can't even begin to count the amount of 'wiring' or 'tune' problems that I've diagnosed to be mechanical issues. That said do everything you can to help, its good for learning and your reputation.

Hi all,

some answers for you.

I usually do road test but this day as rainy and the only wheels was slicks so not a recommended thing.

The weather was about the same temperature but no rain the day after.

Me and the customer live in the same town and the other tuner is a few miles away. albeith they have been in business longer it seems that they do some sketchy things.

I don't know why he refused me to look at the car since he does not return my calls or messages.

Most of the information is hearsay from a thirdparty so i cannot verify or validate but since the customer seems not want to talk to me i cannot get this straightend out.

My own reflection is that it is due to accel-enrichment settings might be off or some other thing regarding trims/ernichment/decel but just speculations.

Regarding the HP number he showed me a photo from their dyno screen on his cellphone. i have to agree that my numbers seems reasonable since it was a m54b28 with "minor" modifications and no boost.

but no correction factors etc.

What I have learnt about dealing with customers is that you need to talk to them a lot. You need to explain as many things as you can in a simple way so they get more understanding of why everything you are doing with their cars is the way it is. I certainly explain difference in dynos, i explain relationship between power limit of the engine and fuel octane rating, importance of engine cooling in terms of overall reliability and so on. That helps a lot to make customer believe that you know exactly what you're doing and builds confidence in your level of professionalism. Also I always tell customer what can go wrong, what's not to be done, what to do if something does go wrong ect... The third thing I certainly do is I always ask customer what he wants - reliability or taking the risk in favor of high power number and explain the consequences - my goal is to hear from customer his own informed decision, not my suggestion.

We usually reply within 12hrs (often sooner)

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