Thread: dyno tune disaster

I don't know where this thread should be posted so I will trust that a moderator will move it to its proper place.
Last Monday I took my car to a large shop to be tuned by a respected tuner that is well known. An employee of the company placed the car on the dyno-wheel and worked the tap-shift feature during the pulls. The tuner was in the car for the first run and stood outside for the other runs. The first three pulls went OK with the performance of the car slowly being increased. However, there was an issue concerning the TC locking and unlocking. On the fourth pull I heard the car go through the gears to third and then they went WOT. At the very end of the pull I heard the car jump in rpms like crazy!!! The car was screaming. It was like a manual being put into neutral and then the gas pedal being pushed to the floor.
The tuner said that right after the pull, the car downshifted into second gear all by itself. He could not offer any explanation of this event. According to what I saw on the graph the rpm went off the screen and the speed of the car was around 137 when it was downshifted.
The car was towed home and we have removed the front head. We have done a seal test with two of the cylinders failing. This is as far as we have gone. We are trying to determine what to do next.
I have spoken to a really good transmission guy about the downshift event, the TC locking and unlocking and the TC being locked up during the 4th run. I will be contacting the TC Company next week.
The tuner has sent me 4 files, but I am unable to open 3 of them because they are HPTs and I don’t have the software.
Can anybody out there give me a hand with this situation? The shop will not return my phone calls, and the tuner was out of town last week, so I am hoping to hear from him this week.
I can forward the files to you via email.

Have you tried to save the HPT files as another file format? Alternatively, if you're not able to open open up the HPT extensions then you should be able to download some free file converter software so you can convert the files into another format.

As far as the tuner goes, I would stay on him until you get an answer if they are going to pay for any of the repairs and go from there. Unless you signed something that says they are not responsible for any damages then I don't see how they could get away with this.

EDIT: Here's a site that might help
http://www.pdftoexcelonline.com/

Ok just to be clear here...the guy actually tuning the car was outside the car during the run in question, but another employee was in the car working the tap-shift?

Originally Posted by Ryan D.

Ok just to be clear here...the guy actually tuning the car was outside the car during the run in question, but another employee was in the car working the tap-shift?

Yes that is correct. He had hurt his knee a few weeks back and it was easier for him to stand the to sit in the car.

I did not sign a release form

That sucks. I think I know what shop your talking about. But anyways it sounds like it was there fault but the chances of them doing anything about it are slim

I just received a picture of one of the downloads peak rpm exceeded 8000 rpms!

8000 rpm? Damn!

Garage Keepers clause. . .

sounds like either some way the guy used the tap shift and down shifted somehow but, i would the the pcm would already know that wasn't safe and wouldn't do that, unless they deleted something in the pcm.

or the guy royally ****ed up your wot shifting, making it down shift from 4th to 3rd at 137 instead of the other way around.

what kind of pcm was it that was in the car when you took it there? stock? or something else?

Send me the files at BillBoost37 at gmail.com and I can open them, save to CSV and ship them back to you. (HPT export feature)

The pcm should have tables in it that don't allow for the car to go that high. As well the fuel cutoff etc should be in place to stop such a thing.

I'm assuming the motor started making some bad noises?

What is Garage keepers clause?

Someone converted the HPT files and sent them back to me on excel

stock pcm. took my diablo tune off and restore original program before handing over the keys

engine noise? Engine was screaming for 1.6 seconds and then shut down. The noise was so loud and high pitched the owner of the shop came to see what happen. They had a hard time restarting it and then started checking codes. Towed home.

Your best bet is to go file a lawsuit in small claims if the damage was under 3000 dollars. This would be an easy win in court especially if you didn't sign a waiver. Simply show up and explained what happened. Have your receipt, invoice, any e-mails conversations, and proof of appointment or service. Then simply tell your story. There is always mediation scheduled before the actual court, where you could work out a settlement before going through with a hearing.

To file should only cost 50 dollars or so depending on what state the incident occurred in.

But I will tell you from experience that your biggest mistake ever would be to allow them to avoid you until the statute of limitations has passed.

After you file, you will not necessarily have to go to court because as I mentioned before, you can always settle. Plus you can move the court date forward to buy a few more months if you want to give the shop time to work something out with you.

I desire to work something out with them. I have avoided and have actually been protecting their names in the public form. One of the problems associated with this situation is, what is the extent of the damage to the engine, transmission and TC? I’m thinking that the only way to determine this is by removing and inspecting every moving part that was exposed to the over rev. Based on the data sent to me 48 hours after the event, was that the over rev lasted 1.6 seconds.

it would be interesting to see about investigating this a while more. Find out what actaully caused it to do that. Maybe the shop ****ed up something, maybe they didn't. Im just saying, find out whats going on then act, dont just blame it on the shop without knowing what is going on. but also like the other guy said, dont let it become too late...

What are your fuel and mph cutoffs in that gear set to? Because our pcms have limiters to keep this very type of thing from happening.

the tuner has the ability to change those numbers to anything he wants. So tuners change them when doing dyno work and some don't.

Any experienced person likes to have fail safes in place. Since you are holding back, I'm assuming you'd rather not discuss it.

There is a folder in the HPTuners editor called Transmission Diagnostics where you can find a few parameters that restrict gear command. Our STOCK numbers are set at 5500 rpm and 62 mph. The rpm and mph must be UNDER these two parameters to enable gear control. MY current modified file on the car is set at 6200 rpm and 188 mph. Looking at my scan, the mph was at 145 mph, below the 188 requirement, and rpm was at 6050 which is under the 6200 rpm requirement which will allow gear command. This explains not only how it is possible to occur but why guys with stock trans tunes or just ratio changes cannot command a downshift when going over a certain speed.

The TC used in my transmission package is not designed to be locked during WOT. The TC was locked during the dyno testing and could have been damaged. Debris could of then of been throw back into the transmission.