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Misfire after Unitronic Stage 2 IS20

MeltedSolid

Autocross Newbie
Location
San Francisco Bay Area
Car(s)
'15 Golf, e36 328i
I thought they had a 30 day refund policy?... Maybe that's only some other tuners... Also, I'm pretty sure if the refund is due to an issue like in your situation, as long as the issue had been brought up within that 30 days that counts (assuming they have that 30 day policy, I believe that's standard for warranties and such). Don't take my word for it though, this has been filtered through my bad memory and opinions.
 

sherbet

Ready to race!
Location
Bay Area, CA
I recently installed an IS20 on my 6 speed auto as well. Same issue here. I have a stock DP (planning to upgrade), and a modified factory air box, ECS intake tube and inlet, Brisk ESR10 plugs. Otherwise stock. Uni Stage 2 91 octane. 3-4 is not playing nice at high rpm shifting. If I let off the throttle as soon as the transmission grabs the next gear and pedal it like a manual, it works, but takes forever to shift.
Last night I tried a 2 gallon E mix, it was fairly cold, ~40 def F. Car performed flawlessly pull after pull, no EPC 3-4 at redline, shifted way stronger than on 91 pump. I think these cars don’t like 91, they need better fuel, especially when you nearly double the stock power levels. I will continue to see how it goes today now that’s it’s a bit warmer out. If the issue persists I will likely look into Reflect.
 

StorableComa

Autocross Champion
Location
SoCal, USA
Car(s)
17 GSW S FWD
I recently installed an IS20 on my 6 speed auto as well. Same issue here. I have a stock DP (planning to upgrade), and a modified factory air box, ECS intake tube and inlet, Brisk ESR10 plugs. Otherwise stock. Uni Stage 2 91 octane. 3-4 is not playing nice at high rpm shifting. If I let off the throttle as soon as the transmission grabs the next gear and pedal it like a manual, it works, but takes forever to shift.
Last night I tried a 2 gallon E mix, it was fairly cold, ~40 def F. Car performed flawlessly pull after pull, no EPC 3-4 at redline, shifted way stronger than on 91 pump. I think these cars don’t like 91, they need better fuel, especially when you nearly double the stock power levels. I will continue to see how it goes today now that’s it’s a bit warmer out. If the issue persists I will likely look into Reflect.
Are you doing your pulls in manual, drive, or sport mode? Spoke with a few other Auto owners and now testing if this misfire issue happens in various modes on the Transmission.

I notice I have these misfires in S mode on the 6spd auto, but never had one when I was logging in Manual mode in 3rd and let it ride out to auto upshift. Going to be testing this again somewhat when I get a chance, but do you recall what mode your trans was in when you did the pull?

Currently IE stage 1 with an IS12 and getting these 3/4th WOT shift misfires. Swapped to RS7 plugs gapped to .024 and APR coils, same misfire EPC issue on 3>4 shift at WOT when winding out the transmission to 6.7k or whatever the raised shift point is. Though when I was logging in just manual mode and forcing it to auto shift I never had these issues.
 

sherbet

Ready to race!
Location
Bay Area, CA
It’s intermittent. Happens in all modes. Last night I went out with 2 gal E mixed with 91, ambient temps were about 40. No issues whatsoever. Seems like with good fuel and low IAT is has
No issues

IS20 Uni stg2 55-100ish
 

jeffdemara

Ready to race!
Location
Vancouver, BC
It’s intermittent. Happens in all modes. Last night I went out with 2 gal E mixed with 91, ambient temps were about 40. No issues whatsoever. Seems like with good fuel and low IAT is has
No issues

IS20 Uni stg2 55-100ish
Thats weird, I tried some E in the tank as well but it made no difference for me unfortunately. I literally tried everything, and absolutely nothing made any difference whatsoever.

Car is running perfect now though back on the stock IS12 with Stage 2, DP, intercooler, turbo elbow, and modified intake with drop in filter. Not once has it misfired or threw any codes since the change back. It’s too bad, I really miss the significant increase in power the IS20 provided. The car felt SO much better
 

jimlloyd40

Autocross Champion
Location
Phoenix
Car(s)
2018 SE DSG
Thats weird, I tried some E in the tank as well but it made no difference for me unfortunately. I literally tried everything, and absolutely nothing made any difference whatsoever.

Car is running perfect now though back on the stock IS12 with Stage 2, DP, intercooler, turbo elbow, and modified intake with drop in filter. Not once has it misfired or threw any codes since the change back. It’s too bad, I really miss the significant increase in power the IS20 provided. The car felt SO much better
Spark plugs probably needed to be gapped tighter.
 

Scanner

Ready to race!
Location
Whitby, ON
Car(s)
2018 Golf TSI 1.8
As far as I know, Unitronic does not have a stage 2 91, only stage 2 93. And their site shows Uni DP as required for stages 2 and above, and especially if you have an IS20. Maybe those could be the reasons for your misfires, possible knockings?
I have a stage 2 IS20 Uni with Uni DP, zero misfires, always smooth, using Petro Canada Ultra 94 gas here in Ontario, no Es.
I do my pulls in manual or sport.
 

jeffdemara

Ready to race!
Location
Vancouver, BC
As far as I know, Unitronic does not have a stage 2 91, only stage 2 93. And their site shows Uni DP as required for stages 2 and above, and especially if you have an IS20. Maybe those could be the reasons for your misfires, possible knockings?
I have a stage 2 IS20 Uni with Uni DP, zero misfires, always smooth, using Petro Canada Ultra 94 gas here in Ontario, no Es.
I do my pulls in manual or sport.
I have all the supporting mods, as well as Chevron 94 octane and I mixed some ethanol to get to an E20 content which took away all timing reductions. Issue still persisted.

Are you DSG trans, or the regular auto 6spd slushbox ?

friend of mine put the exact turbo that was on my car, on his car, and its flawless, even without ethanol in tank. No misfires. Only difference is he’s DSG, I’m not.
 

Scanner

Ready to race!
Location
Whitby, ON
Car(s)
2018 Golf TSI 1.8
6 spd slushbox. I wonder what was the main cause of your issues with your Uni IS20. I guess we will never know. I know another guy here in my area with the same IS20 config, 6spd slush and no issues.
 

Daks

Autocross Champion
Location
Toronto
Car(s)
GTI PP
As far as I know, Unitronic does not have a stage 2 91, only stage 2 93. And their site shows Uni DP as required for stages 2 and above, and especially if you have an IS20. Maybe those could be the reasons for your misfires, possible knockings?
I have a stage 2 IS20 Uni with Uni DP, zero misfires, always smooth, using Petro Canada Ultra 94 gas here in Ontario, no Es.
I do my pulls in manual or sport.
I'm running a 91 OCT stage 2 Uni tune, just call them and ask for it. I did, and that's how I got it.
 

Scanner

Ready to race!
Location
Whitby, ON
Car(s)
2018 Golf TSI 1.8
I'm running a 91 OCT stage 2 Uni tune, just call them and ask for it. I did, and that's how I got it.
That's good to know. Uni could have those 91 options for stages 2 and above on their website as APR have.
 

danbfree

Go Kart Champion
Location
Portland, OR suburbia
Car(s)
2017 Golf 1.8 TSI
So reviving this as I was having the same issue myself with APR tune with 1.8 IS20, EPC when trying to rev out past 6000 RPM. VERY, VERY long story short, I came up with a solution after pulling what little hair I have out. Although some have resolved their issues with plugs, and coils, etc, my mods are in my signature, fresh step colder RS7 plugs gapped to .024 I just couldn't fix it either. It seems like enough of a universal problem with those of us with the 09G that you would think that someone other than Ian@Reflect could do an "09G compatible tune".

Without further ado, the solution for me was to stack with a JB4 and create a custom boost curve in Map 6, no other changes, just the new boost curve *with a taper off up top starting after 5500 RPM*. These are my logs where I simply taper the boost down starting at 5500 RPM. To me that's literally the solution for my car. It even feels pretty smooth without running out of breath as timing takes over more when the tune sees low boost up top. I did start with 91 octane w/aftermarket DP but used a 2nd out of 3 included reflashes for free to downgrade to their lowest 87 w/stock DP tune and it was still an issue until I did the custom boost curve. Now, gonna go back to the 91 but with stock DP so I get more timing back for low end response but w/stock DP option it keeps the boost a little more safe to work with and still very decent power peaking at about 23-24psi on 91.

I must add, as part of the process I contacted APR support and without using these words myself, only describing the problem, THEY even said it was likely "transmission torque limit". Now that I have found a fix, I don't want to have to live with a JB4 connected all the time to fix a bad tune for an 09G when I shouldn't have to, so I'm hoping they will offer me an adjusted tune or I get my money back and it goes to Ian, who I'm sure will work with me on a custom curve that works for me.

Full-ish pull -datazap.me | danbfree | Torque limits fixed, just needs boost taper up top.

3rd into 4th "Punch it Chewy" - datazap.me | danbfree | Boost fixed 3rd-4th punch

I may still have a bit more in 'er too, this is just what I am at for now, tired of burning $5 gas up for the moment. :)
 
Last edited:

RHaas

New member
Location
Temecula, CA
Car(s)
2015 Golf Wagan
Keeping thread alive with me having same issue, similar build. I recently installed IS20 with 91 octane APR tune. California car. 2015 GSW, stock down pipe, 6speed auto FWD. APR Intake. I was APR Stage 1 for 2 years with zero issues. Car now has 100k miles, did the IS20, new plugs gapped to 0.024 a few weeks ago. Issues started right after the turbo upgrade. Nothing else was changed. WOT, High RPM misfires, mostly top of second gear going to third. Ruled out ignition issues, fuel trim is good. Took to local shop, they confirmed no ignition or fuel pump issues and suggested I should replace injectors and walnut blast the intake valves due to mileage on car. Will let you know the outcome. Fingers crossed. *
 

Daks

Autocross Champion
Location
Toronto
Car(s)
GTI PP
Keeping thread alive with me having same issue, similar build. I recently installed IS20 with 91 octane APR tune. California car. 2015 GSW, stock down pipe, 6speed auto FWD. APR Intake. I was APR Stage 1 for 2 years with zero issues. Car now has 100k miles, did the IS20, new plugs gapped to 0.024 a few weeks ago. Issues started right after the turbo upgrade. Nothing else was changed. WOT, High RPM misfires, mostly top of second gear going to third. Ruled out ignition issues, fuel trim is good. Took to local shop, they confirmed no ignition or fuel pump issues and suggested I should replace injectors and walnut blast the intake valves due to mileage on car. Will let you know the outcome. Fingers crossed. *
That most likely won't be the cure
 
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