[SOLVED] Throttle/Boost Cut/Misfire on Partial Throttle?

I would genuinely appreciate some clarification on the hate toward DramaTuned. I tried searching these forums for answers, but only found yourself and Enki hating on his work without any real reason why. I'd like to make an informed decision but don't have any information to go off of.

Additionally, let's say it is the tune, why would this start happening recently when nothing has changed in nearly a year?

 

You might not have access to it, but there's a thread dedicated to him here in the members only section.

 

I tried to view that but did not have access, unfortunately. Is there a way to make it public to see?

 

An OTS tune will certainly help identify if it is in fact the tune causing the problem.

I am not familiar with any tuners for this platform, but I believe your point on the fact that this is a new issue would potentially eliminate the tune from being a problem.

I also like how thorough you are with your diagnostics and analysis. Assuming you can easily recreate the problem, I say try an OTS temporarily under low load and see if your problem goes away.

 

From my OP in said thread:

 

yup entire thread dedicated to his shenanigan's, poor tunes, ripping off other ones and preforming worse than cobb ots maps. many pages long at this time. given the area it's in not making it public, although that is an idea to use as a warning.

Change in temps could make some issues in theory if the logic isnt applied properly . Now it seems that it could be the throttle body connection or the throttle body itself as well based on where we seemed to have narrowed it down to.

BUT how does the car perform at WOT any logs for that?

 

It honestly looks like the throttle close load settings are off for cruise. I've experienced these symptoms myself and know exactly how to duplicate it in the tune.

Edit: Another test would be to apply more throttle when it gets to the point where it starts doing that. If that fixes it, could still be tune. I would imagine you'd be able to find these issues (and log them) at idle or higher throttles, not just cruise.

 

I can see temperatures being the potential cause, it's getting hot here. Here's some logs during WOT.

3rd to 4th gear WOT (E30)
4th gear WOT (91)

I will try to give it more throttle and see if it persists. This issue only seems to be at partial throttle, but I will start to log my pulls just in case it shows up during one of those.

 

Here's the thing.
Air density changes with temperature, as you likely know. The MAF compensates for this by checking temp as well as flow rate of incoming air, so there *should* be no issues here, as the tune should automatically compensate for this.

However, the one thing that does change that requires special attention is turbo flow characteristics. Spool itself will change, so if it was tuned (poorly) in the winter, the airflow curve at a given throttle input can change with the temperature. The same effect can happen with altitude changes.

Thus if your tuner is lazy, and does copy paste crap for your map using a base map from another car with another turbo, you're likely to have issues.

That said, let me ask you this:
What did you have to provide to drama to get this tune you're running?

 

The section being referred to is in the supporting metal member section.

 

Just a quick update, but I had the issue happen WOT during a 3rd gear pull. Unfortunately did not get it on log, but it was the same quick interrupt. I will continue to try and get a log of it happening during WOT.

My tuning process was quite long and took several months and iterations as I was having issues that ended up being injectors, EBCS, MAF, etc. When all was said and done I did 7 revisions of the 91 tune and 20 of the E30 tune. I don't expect this to be normal what so ever, but then again my car isn't friendly. The logs requested were initially a MAF test, AC idle test, and then a 4th gear WOT pull for each revision, however toward the end it was simply the 4th gear WOT pulls as he was dialing in the performance.

 

Quite long with who? Drama or both?

 

Both my 91 and E30 tunes are from Drama, my bad.

 

Was he the only one that tuned you or did you have another tuner previously? And did you seriously replace all your injectors from what he said?

 

I bought the car with a Drama tune and then had both 91 and E30 tunes revised after some stuff was done to the car.

Just noticed you said replaced, however I simply took them out and had them serviced. His recommendation was as such, which I absolutely did. Keep in mind, while you may have this negative perception of his work, I've only ever heard great things about him until this thread, so I took what he said very seriously. That said, I sent my injectors to Overspeed and they were shit, so it was a good thing to have done.

The seals were also OEM which were also shit, so I put some nice aftermarket ones in at the same time.

 

Not sure how the car was running with only 42cc flow rate. This was probably done at 40 psi instead of the 400 - 1800 that the injectors regularly see though.

 

Yeah it looks like based off the sheet it was done at 43psi. I didn't see anybody that flow tested them at the high pressures the HPFP puts out, but a lot of people recommend Overspeed and the turn around time was what I was looking for as well.

 

Sounds like a tune issue

 

Following up in case someone stumbles upon this in the future. As suspected, it was not a tune issue. I did replace the throttle body, but that didn't solve it. The issue progressed into a quick misfire that I got during a WOT run and that prompted me to replace the spark plugs. I have not experienced this hiccup anymore since, but I suspect it was misfiring all along and wasn't throwing a code for some reason.

 

I had a long term mid range miss that would not trigger a cel which turned out to be a spark plugs which had opened its gap up