slktyperice

Good info. So what was stock?

dave405nyc

ha! I downloaded the app after I installed the JB+. I'm too lazy to remove the tune and re-test lol. I will eventually test it stock whenever I get the chance.

jctevere

I dunno, I'm a bit concerned about putting this on my vehicle. It is only a lease, so I'm not too concerned, I just hope it doesn't void any warranty if anything does happen. This is because my car has already once thrown a CEL under 3/4 acceleration. The car seemed to have missed or failed to shift...



It is pretty cheap though. Does anyone have any idea about warranty? If anything does happen - I guess I can just remove it and bring the car in?

dave405nyc

What % was it set at? I believe Terry said that if a CEL comes up, to just restart the car and it will disappear.

jctevere

That was 100% stock - I didn't buy the tune yet. I was simply stating that if I was having problems before it, I am leery about getting it, since it might make the CEL happen more often...

When I went to the dealer, he pretty much seemed like he had no idea what the error code was. Probably thinking I don't know anything about cars like most Mercedes owners, he said, "The Check Engine Light code told us that the car needed parameters changed, so we changed the parameters and you shouldn't have any more issues, if you do, just let us know."

So to me, it seems that it through some kind of error (and I would guess in the tranny as it did a weird shift) and all they did was clear the code and that was it.

I'm not so sure that restarting the car would get rid of a CEL either. Because as soon as my issue popped up, I restarted the car, and the CEL remained illuminated for days, until I went to the dealer to get it cleared, even though operation was back to 100% normal.

Perhaps some of our more "mechanically informed" members could comment and validate kenny's claims?

But bottom line is, I think of it like this: It is only a lease, and it is removable. sO I think that for under $300, with a rather high potential benefit, I will just get it and try it out, and if I have any problems, will take it out before bringing it into the dealer and just "act stupid". Does anyone know if the dealer has ANY way of knowing if something was used even if the module is removed? As in, has a black box that records boost, etc, at errors?

dave405nyc

Would you happen to know what the error code was? Should hopefully be listed on the work order receipt.

I say to still get the JB+, totally worth it. I've had it on since January with no issues @ 65%. And if a CEL came on, I would read the code to make sure it's not related to the tune, and clear it. If it comes back on, then I would take it to the dealer (sans tune).

MDMercedesGuy

Along the lines of the same question, can you elaborate a bit on the missed or failed shift? Did it seem to rev higher, or was it just jerky?

I have had 1 or 2 seemingly rough shifts, but I think it is still trying to learn the parameters of my driving and such. Coming from a smart, an automatic 1975 240D would seem smooth.

silversx

have any of you guys hit overboost on the tune? feels like you're pulling hard and then bam.. engine cuts out for split second because boost too high

i think i hit overboost today.. but weird thing is was not flooring it.. just pulling kinda hard..

Igor1080

Can't say I've noticed something like this happening. But I did notice the power is inconsistent, some days the car seems more powerful than others.

jctevere

Unfortunately I don't know what the error code was... I just dropped it off at the dealer, and picked it up later in the day, was kind of in a rush.

As far as "missed shift". I meant that it seemed like it slipped. It was as if the car went to shift at like 3,500 rpm. But the rpms spiked to like 4,000-4,500 and the engine power dropped off. Then the CEL came on. Then I just pulled over, restarted it and it was normal.

And yes, I have noticed that a few shifts are a bit more "rougher" than ususal. Especially the first shift from 2nd - 3rd gear after just starting the vehicle (cold start).

MDMercedesGuy

I'm trying to be good during the break-in period... I'm at 560 miles now. It's been punched a couple of times, and I did have one particularly brutal highway run playing with my boss in his C300. That said, I've had it in S mode like 2 times - but it makes a noticeable difference. I want to wait to get it past 1,000 miles before I really start playing with it - but S seems so much smoother.

dave405nyc

I've felt it as well, it cuts power for half a second (mostly happens at 3500rpm for me). Only happens once in while tho, and in the higher gears. Hopefully Terry will address that issue with a software update.

dave405nyc

Seems like it's an isolated issue, if it just happened that one time. Don't let this sway you from getting the tune, it's totally worth it for less than $300.

As for the tranny shifting, mine is butter smooth. Maybe you can get it checked out at the dealer before you put on the tune?

DameMD

Well, since I bought one of the first beta JB+ tunes, I thought I would chime in. I have over 1500 miles on JB+ tune. This is my driving impressions and may not reflect what others are experiencing.

1) I do hit the over-boost (CEL) quite often. When this happens, the ecu/engine cuts the power and seems like the turbo is not even working. It feels like a 3500lb car running on a Toyota Prius engine. The car get lethargic but is still drive-able .Turning the car off and then back on, puts everything back to normal.

Now this is not BMS fault, as they warned people not to dial up boost too high. I did mess with the boost dial, and turned it up to 85-90%. When I was at the stock 60% I maybe had one or two over-boost CEL. Will I go back to 60%? NO. Will I keep running at 85-90%? probably not as the over-boost CEL is quite annoying especially if I am driving in traffic and loose the turbo power. I will turn the boost down to about 70-80% this weekend.

2) I leave the car in "S" most of the time. Though the tune helps with some of the lag in "E", there is still lag and I think the lag combined with the extra boost messes with the engine and contributes to the CEL. I recommend keeping the car in "S" when getting the JB+ tune. Plus when in "S" I rarely get over-boost CEL as lag is minimal, and it doesn't seem like your waiting for the turbo to spool up as much.

3) The power is great. I WILL NOT/WOULD NOT go back to stock. I don't care how many times i get a CEL. The car is not "Fast" but a lot quicker than it was stock low-end. No power up top so don't look for it. As a comparison my friend has a c350 prior to the 2012, and my car is quicker to about 0-80. I have not done triple digit runs as I don't need to go that fast where I drive so I can't compare high-end.

4)Gas mileage LOL. I am not getting nowhere near the great gas mileage I was getting stock. I don't ***** about gas prices, and I know this car was not a best bargain in that department. Also, I do mostly city driving and I drive hard. :-)

4) This isn't an Audi/VW or BMW that comes with a bigger engine and turbo. There are not many options as far as tune's unless you want to pay upwards of $1000+. The c250 turbo is weak however, for $300 (I paid $179) for the JB+ tune, there is nothing right now for this car that can even compare bang for buck performance. I rather continue using the tune and deal with the CEL if it happens after I turn down the boost.

All-in-all, I like the JB+ tune and I can't wait for stage 2 + intake and other goodies. :-) Nice job BMS!!

DameMD

Also, Idk why some of you are not experiencing the increase in power. 43+ torque is a lot. That means we have the same amount of torque as the 2012 c350 and more torque than the prior years c350. Of course if you are doing a lot of top speed runs, I can see you are not feeling any difference but low-end is definitely an improvement. I drive hard, and always in "S" and use paddle shifters when I want to get off the line quicker. I know HP is what a lot of you want but, around town/city driving the added TQ is great. I hope after some of you spend more time with tune and the ecu learns your driving habits, your cars will feel more alive.

slktyperice

Speaking of which, any of you guys interested in selling your JB+ if you don't like it?

Igor1080

I felt the power since day 1. I do however have an issue where the car makes a loud whining noise when driving it cold. If it just starts up and the car is in E, the engine is very whiny and temperamental. In S mode, I haven't experienced any CEL's and I don't think I've hit overboost before. I also dialed it up before installing and I've been running the car at 80% since day 1. I cant definitely say this is a crazy improvement over stock in terms of $ for $ mods. Theres barely any mods for this car at the moment what-so-ever, the market basically doesn't exist.

Also I have a concern about the box being in a high heat area and I would hope it doesn't succumb to any heat issues during the hot NY summer. I mean even microsoft had issues with a mass produced product like the Xbox and solder melting, I would hope that this thing is not susceptible to similar problems.

dave405nyc

I think the whining noise while the engine is cold is relatively normal. I would hear the whine when I hit boost. I had the same exact issue with my A4 2.0T. After about a few minutes, the whining goes away.

Igor1080

I think its become a little louder now that I have the JB tune. The tune might be straining the engine by activating the turbo while the car is cold (thats just my hunch, I don't have any real basis for that guess). Either way I think it's louder with the tune than without.

DameMD

I haven't heard the winding noise either on start-up. When I shut the car off after spirited driving I get the winding noise.

Also, my GTI makes the turbo winding sound once I turn the car off from spirited driving too. I think it's normal.

nlpamg

how long does the winding noise go for? I'd assume that it's excess exhaust gasses passing through the turbo after the car has stopped and that it shouldn't last for more than a few seconds.

my GT-R does not make any such noise after it has shut off. this is the only other turbo car I've had, so I can't really comment further.

MDMercedesGuy

Are you guys idling your car down after you drive it?

I guess I am a bit old school from the turbos I have read about in the past/the buses I used to drive during college and needing to be idled down. I pretty much give it a minute or two after I park to let it rest before I pop the key off.

Igor1080

I'm leasing so I really don't care about maintaining the car to that degree. I don't really take the time to warm up the car either. I keep it super clean, I don't beat on it and I make sure its functioning properly. Thats about the extent of my car care.

silversx

so you actually get the check engine light? i've never gotten the light and have since not been in overboost.. i have my tune at whatever it was shipped at .. 65% what terry said

maybe you can have the code read if you actually get a check engine light when overboost happens

jaungar

I installed the jb stage 1 and definitely felt the difference, and i'm waiting aditional updates.