Hey guys, quick question. Has anyone ever had issues starting the car after the car is warmed up and hot? I buddy bought a used jb4 and in the morning the car starts up fine, but after 2 or 3 starts the car takes a long time or won't crank on the first try. On map 0 it doesn't do it, but on map 1 and 2 it does. Any thoughts?
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BMS VW GTI JB4 info thread
- Thread starter George Smooth
- Start date
Sounds like something's up though sometimes this is coincidence. I'd recheck the connections and load latest fw to reset it. I would have thought maybe the fuel wire was part of it but it's not even required on map 1. I suppose that if the fuel wire is giving false instead of no added readings, it could cause an issue on map one as well. Also check the settings like fuel add etc and make sure they are at default.
Alrighty will do! I appreciate the help!
forgot, you can also use the jb4 to scan for a fault code. https://drive.google.com/file/d/1C7...US8iVmSITQjNiuZ3e4Rhy7tfzHFDPzWgY87uXXsjm1kvc
I'm trying to decide whether to get a JB4 or a custom ECU + TCU tune (made in dyno) from a local shop with extremely good customer feedback. The cost difference is about 400 dollars. I like the easy connectivity and possible resale value of the JB4 but still I'm not sure.
Is it true that the JB4 stage2 is mostly noticeable above 3000rpm? And by this I mean do you really benefit of the tune in normal day to day driving? I believe the custom tune lets me have more fun also in the lower rpms but i might be wrong.
What do you guys think? Any feedback is highly appreciated.
Is it true that the JB4 stage2 is mostly noticeable above 3000rpm? And by this I mean do you really benefit of the tune in normal day to day driving? I believe the custom tune lets me have more fun also in the lower rpms but i might be wrong.
What do you guys think? Any feedback is highly appreciated.
up4speed
Go Kart Newbie
- Location
- Long Island
- Car(s)
- 2015 GTI
I haven’t tried any of the other tunes, only the JB4. So far I really love the JB4.
Something to consider, these cars have good torque down low even on a stock tune. It is hard to lay down all the power even in stock form when you are at lower RPMs. With the JB4 you can break down how much torque/boost you want at each (500) RPM. All the way down, I am adding zero boost to the stock mapping under 2500 Rpm, because it is useless, since it will just spin the tires and go nowhere if I floor it. .In other words, you can add power if you please so down low it will be as much boost as you would like.
I also like that with the JB4 you can keep an eye on things by doing driving logs to make sure that everything is safe, and not pulling too much timing or leaning out the fuel ratio too much., and if you decide that it pulls too much or too little in a certain RPM, you can tweak it and make it more linear, Or peaky depending how you like it. Also if the weather changes dramatically, you can adjust for that as well. Unfortunately, to do all that you have to do a lot of reading and learning, I am in the process of learning, but I think I have it figured out mostly, If you are not confident, or willing to take the time/risk, then may be it is better to go with a tune, instead of the JB4.
Overall, I am thrilled with the JB4, and impressed at what it does for the price. I am enjoying mine!
Something to consider, these cars have good torque down low even on a stock tune. It is hard to lay down all the power even in stock form when you are at lower RPMs. With the JB4 you can break down how much torque/boost you want at each (500) RPM. All the way down, I am adding zero boost to the stock mapping under 2500 Rpm, because it is useless, since it will just spin the tires and go nowhere if I floor it. .In other words, you can add power if you please so down low it will be as much boost as you would like.
I also like that with the JB4 you can keep an eye on things by doing driving logs to make sure that everything is safe, and not pulling too much timing or leaning out the fuel ratio too much., and if you decide that it pulls too much or too little in a certain RPM, you can tweak it and make it more linear, Or peaky depending how you like it. Also if the weather changes dramatically, you can adjust for that as well. Unfortunately, to do all that you have to do a lot of reading and learning, I am in the process of learning, but I think I have it figured out mostly, If you are not confident, or willing to take the time/risk, then may be it is better to go with a tune, instead of the JB4.
Overall, I am thrilled with the JB4, and impressed at what it does for the price. I am enjoying mine!
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The tunes will feel stronger below 3k but it's mostly enhanced throttle response since there's no added boost and the stock motors already run a lot of advance there. Get a throttle controller and set it to lowest enhancement and it completes the JB4 tweak. Even the cheap ones are ok set like this. Better to get one that you calibrate 1st. That's not to say the flashes aren't more comprehensive. A good one is but my butt dyno is very happy with this JB4 plus throttle controller setup.
I guess you have an OPF GTI Performance, are you keeping stock DP and that local tuner does he have experience tuning those?
OPF IS38 cars do pretty good on JB4 and stock DP with some E85 but not sure I have seen a GTI yet.
Actually his first question was about the opf/gpf filter so yes he is very knowledgeable about the technicals. The filter isn't a problem.
I know that JB4 makes good power, I've had couple in my BMWs earlier. That wasn't really the point of my question. I'm looking for the best day to day driveability and really aren't that interested in fiddling the settings all the time. Also the numerous dyno pulls during the tuning should help to get it spot on...
The car has K&N panel filter, turbo inlet and will be run daily with 98 octane fuel with 5% ethanol in it.
Thanks for the input so far.
I have not used the JB4 since 2019 so can not really comment on the drivability on the latest firmwares but I really hated the stock DSG tune and almost always drove it in manual. If warranty is not an issue a good ECU/TCU tune combo is better for sure.Actually his first question was about the opf/gpf filter so yes he is very knowledgeable about the technicals. The filter isn't a problem.
I know that JB4 makes good power, I've had couple in my BMWs earlier. That wasn't really the point of my question. I'm looking for the best day to day driveability and really aren't that interested in fiddling the settings all the time. Also the numerous dyno pulls during the tuning should help to get it spot on...
The car has K&N panel filter, turbo inlet and will be run daily with 98 octane fuel with 5% ethanol in it.
Thanks for the input so far.
Has this been confirmed anywhere? I've also read this as well but having trouble finding confirmation or validation. Just recently got in a used JB4 and am really curious. Looking to set and forget.
I don't think that's the case. Map 6 before user adjustment is supposedly Map 2 with less boost at lower RPM. https://www.n54tech.com/forums/showthread.php?t=50428
That's what George said. The boost on Map 3 comes on later than is does on Map 2.
I like Map 2 more than 3. I get that kick in the pants sooner in Map 2. I'm DSG though.