[tomchang75]

Hi bimmer owners,

I been considering getting JB4, but before doing so I have some questions.

1. With JB4, Has anyone experience problems failure on coil, spark plug, injector or other parts?

2. With JB4 alone, what is the power and torque gain? Does it take your car to another level with just map 1?

3. The tech told me simply resetting JB4 to factory or map0 before going for smog check and the car will pass the test. True?

4. Please share your experience with JB4 and the do you recommend going with it.

Thanks

[fazman]

Originally Posted by tomchang75

Hi bimmer owners,

I been considering getting JB4, but before doing so I have some questions.

1. With JB4, Has anyone experience problems failure on coil, spark plug, injector or other parts?

2. With JB4 alone, what is the power and torque gain? Does it take your car to another level with just map 1?

3. The tech told me simply resetting JB4 to factory or map0 before going for smog check and the car will pass the test. True?

4. Please share your experience with JB4 and the do you recommend going with it.

Thanks

Answers:
1) All parts when stressed more will need more frequent tune ups, you gotta pay to play my friend. But if you have a good Indy mechanic or are handy with basic tools... these cars are pretty easy to fix but it's a lengthy time consuming process to fix them (not as simple as Japanese cars).

* Coils will fail sooner then they would have at only stock levels (Coils are fairly inexpensive at about $40-$50 each). Expect to get a cyl misfire error as your hint that it might possibly be a bad coil/spark plug/carbon blasting time. Sometimes you will get a cyl X misfire code but the real fix was to replace coil/plug for X+1 or coil/plug X-1. If one is bad... just change them all cuz they are all not too far behind. You can also use the n55 coils which are the same thing but a little cheaper (dealer put in the n55 coils in my car when they covered it under CPO). The way they worded it was, "changed one coil with a different type than the other 5 coils and spec requires all coils to be the same so we need to change all 6 coils" $50 CPO and i got all new coils... ta-da!

* Plugs will fail sooner then they would have at only stock levels. Non-dealer plugs are priced at about $12 each vs dealer prices of about $25 each. The stock mileage to change them at is about 45k miles. If your running a tune, you should expect to change them every 25k miles or so. Always just change them in sets of 6

* Injectors on these cars are Meh, they fail it's about $150 each and you need to change them out in sets of 3 for the entire bank. Has nothing to do with the JB4, it's just a crappy design. I had mine changed by the dealer under cpo as well, got the new revision... previously I had one bank of original injectors and one bank of recalled v2 injectors (now they are all v3 injectors).

* other parts - Your air filter will get dirty (clean or replace), your HVAC filter will get dirty (replace with a Mann charcoal filter from amazon for $18). You will need carbon blasting (Indy should do it for about $250-$300 range, more than that and you should keep hunting for a more competent mechanic). Your Charge pipe which is plastic will probably blow off or crack at some point (should should get an ER Charge pipe anyways). Your plastic DV/BOV will probably start to leak... get a nice one when you buy your ER Charge pipe, like a Tial-Q. Basic maintenance becomes all that more important to do on time with fluids. Change your motor oil every 7500 miles (don't listen to the OBC)... I would use the Mobil1 5qt 0-40 euro flavor jug from Walmart @ $22 each jug and a Mann oil filter from amazon for $10. The Mobil1 oil actually helps keep your Oil temps about 10*F cooler over the dealer Castrol oil changes... so the proof is in the pudding.

2) Read the BMS website for it's details and the N54tech site for what issues/concerns you should be aware of. No matter what... you will love the JB4. Just set it to Map 5 (auto tune) and just enjoy driving. FWIW, I can get 33 MPG doing all freeway on my XI with the JB4 over a 900+ drive. The same drive back home on map 0 gave me 27 MPG. I did the run using my cruise control at 5 MPH over the limit the entire drive to make as much of an apples to apples comparison.

3) Map 1 and above have the JB4 enabled which means the OBD2 port can not be communicated with (which is what the DMV needs to check for "readiness"). When you set the car from Map 1 or above --> Map 0 all the "readiness" values are RESET and since your car has not reached "readiness" the inspection place will say come back another day after driving around for a while. So you need to do a "Drive Cycle" on Map 0 so the car can reach "readiness" on Map 0 before you get it inspected. do a google search on what that process is, its not hard to do if you know what is needed (just don't keep flipping maps cuz it keeps resetting the readiness each time you change maps and you will need to start ALL OVER AGAIN). So the short answer to your question is YES

4) Yes, get it. Buy the JB4 + USB Cable + DCI... it will be the best money you ever spent on modding your car. The second best mod will be to ditch the RFT tires and get normal Go Flat Tires!!!!! After that... you should invest in a FMIC, it won't add any power... but it allows you to make the same normal power pull after pull, with the stock FMIC you get heat soaked after the first pull and then you lose a lot of power.

[e90'D10]

Originally Posted by tomchang75

Hi bimmer owners,

I been considering getting JB4, but before doing so I have some questions.

1. With JB4, Has anyone experience problems failure on coil, spark plug, injector or other parts?

2. With JB4 alone, what is the power and torque gain? Does it take your car to another level with just map 1?

3. The tech told me simply resetting JB4 to factory or map0 before going for smog check and the car will pass the test. True?

4. Please share your experience with JB4 and the do you recommend going with it.

Thanks

As mentioned above any parts giving more stress to the engine will cause some issues down the road regardless if it's OEM or aftermarket.

1. I had the JB4 G5 ISO on my last 335i and I had no issues which I was running the set up for about a year or so.

2. It does take your car to another level on map 1 but it's best to use map 5 as it'll adjust and fit YOUR car correctly. Power gains varies on your set up (e.g. DCI, DPs, CAE, FMIC upgrade, BOV, CP & etc).

3. I'm not a tech but when I've had my car serviced running the JB4 G5 I had no issues from being turned away or failing "any" test.

4. Installing the JB4 G5 ISO was the BEST decision I ever made for that car coming from a built Evo VIII making close to 600 AWHP. Granted I knew it wasn't going to be close to what I drove before I owned my first 335i. Yet it did make me smile which in my eyes was a plus. The features that come with it I felt were extremely beneficial.

Overall best bang for your buck!

[HCGxKaLiBeR]

I have a 46k miles car, installed JB4 a few months ago.

Last week I got a misfire. Engine service light came on, engine performance drop, car shakes when stopped, but it went normal after I restarted the car

Been red line testing a few times, misfire never happened. So, idk what might have cause it.

As for performance, Map 1 or 5 will let you feel different from stock turbo boost. Where I live does not have a dyno shop, but the power is definitely noticeable.

Map 0 = stock car. So it is the best to switch back to stock before perform any tests.

Getting a JB4 with a cold air intake and maybe a charge pipe with BOV are enough for beginner. These are very easy to self install.

[JoeyH335i]

sub*

[335NJ]

Originally Posted by HCGxKaLiBeR

I have a 46k miles car, installed JB4 a few months ago.

Last week I got a misfire. Engine service light came on, engine performance drop, car shakes when stopped, but it went normal after I restarted the car

Been red line testing a few times, misfire never happened. So, idk what might have cause it.

As for performance, Map 1 or 5 will let you feel different from stock turbo boost. Where I live does not have a dyno shop, but the power is definitely noticeable.

Map 0 = stock car. So it is the best to switch back to stock before perform any tests.

Getting a JB4 with a cold air intake and maybe a charge pipe with BOV are enough for beginner. These are very easy to self install.

How many miles on spark plugs? If they have more than 25k on them they should be changed, if the misfire continues, move the coil pack for that cylinder and see if it follows the coil. I'd bet that's the cause of the misfire since it's so common.

[HCGxKaLiBeR]

Originally Posted by 335NJ

How many miles on spark plugs? If they have more than 25k on them they should be changed, if the misfire continues, move the coil pack for that cylinder and see if it follows the coil. I'd bet that's the cause of the misfire since it's so common.

Never changed since I bought the car.... I will consider change it when it happens again. They are easy and cheap to change anyway.

So far, it only happened once. (When I floored it from 3k RPM)

[335NJ]

Originally Posted by HCGxKaLiBeR

Never changed since I bought the car.... I will consider change it when it happens again. They are easy and cheap to change anyway.

So far, it only happened once. (When I floored it from 3k RPM)

I'd just keep an eye on it, but I'd do them anyway since its a fairly cheap job to play it safe. When tuned, 20-25k is the recommended interval. The last thing you'd want is a misfire/limp when WOT at 6,500 hauling ass.

[mike@x-ph.com]

Originally Posted by tomchang75

Hi bimmer owners,

I been considering getting JB4, but before doing so I have some questions.

1. With JB4, Has anyone experience problems failure on coil, spark plug, injector or other parts?

2. With JB4 alone, what is the power and torque gain? Does it take your car to another level with just map 1?

3. The tech told me simply resetting JB4 to factory or map0 before going for smog check and the car will pass the test. True?

4. Please share your experience with JB4 and the do you recommend going with it.

Thanks

1- Yes. The JB4 will expose weak components . The components will eventually fail, the Jb4 will just expose them couple weeks/months sooner

2- Jb4 alone adds around 100 HP crank to the car, yes it will transform the car alone.

3- JB4 alone will not cause you to fail a smog no matter which map you have on. It is always recommended to reset it to map 0 but you can still pass with any map.

4- I am pushing 450+ whp and i never get bored with my car.
Yes i recommend going with it

[Jeff@TopGearSolutions]

Originally Posted by fazman

Answers:
1) All parts when stressed more will need more frequent tune ups, you gotta pay to play my friend. But if you have a good Indy mechanic or are handy with basic tools... these cars are pretty easy to fix but it's a lengthy time consuming process to fix them (not as simple as Japanese cars).

* Coils will fail sooner then they would have at only stock levels (Coils are fairly inexpensive at about $40-$50 each). Expect to get a cyl misfire error as your hint that it might possibly be a bad coil/spark plug/carbon blasting time. Sometimes you will get a cyl X misfire code but the real fix was to replace coil/plug for X+1 or coil/plug X-1. If one is bad... just change them all cuz they are all not too far behind. You can also use the n55 coils which are the same thing but a little cheaper (dealer put in the n55 coils in my car when they covered it under CPO). The way they worded it was, "changed one coil with a different type than the other 5 coils and spec requires all coils to be the same so we need to change all 6 coils" $50 CPO and i got all new coils... ta-da!

* Plugs will fail sooner then they would have at only stock levels. Non-dealer plugs are priced at about $12 each vs dealer prices of about $25 each. The stock mileage to change them at is about 45k miles. If your running a tune, you should expect to change them every 25k miles or so. Always just change them in sets of 6

* Injectors on these cars are Meh, they fail it's about $150 each and you need to change them out in sets of 3 for the entire bank. Has nothing to do with the JB4, it's just a crappy design. I had mine changed by the dealer under cpo as well, got the new revision... previously I had one bank of original injectors and one bank of recalled v2 injectors (now they are all v3 injectors).

* other parts - Your air filter will get dirty (clean or replace), your HVAC filter will get dirty (replace with a Mann charcoal filter from amazon for $18). You will need carbon blasting (Indy should do it for about $250-$300 range, more than that and you should keep hunting for a more competent mechanic). Your Charge pipe which is plastic will probably blow off or crack at some point (should should get an ER Charge pipe anyways). Your plastic DV/BOV will probably start to leak... get a nice one when you buy your ER Charge pipe, like a Tial-Q. Basic maintenance becomes all that more important to do on time with fluids. Change your motor oil every 7500 miles (don't listen to the OBC)... I would use the Mobil1 5qt 0-40 euro flavor jug from Walmart @ $22 each jug and a Mann oil filter from amazon for $10. The Mobil1 oil actually helps keep your Oil temps about 10*F cooler over the dealer Castrol oil changes... so the proof is in the pudding.

2) Read the BMS website for it's details and the N54tech site for what issues/concerns you should be aware of. No matter what... you will love the JB4. Just set it to Map 5 (auto tune) and just enjoy driving. FWIW, I can get 33 MPG doing all freeway on my XI with the JB4 over a 900+ drive. The same drive back home on map 0 gave me 27 MPG. I did the run using my cruise control at 5 MPH over the limit the entire drive to make as much of an apples to apples comparison.

3) Map 1 and above have the JB4 enabled which means the OBD2 port can not be communicated with (which is what the DMV needs to check for "readiness"). When you set the car from Map 1 or above --> Map 0 all the "readiness" values are RESET and since your car has not reached "readiness" the inspection place will say come back another day after driving around for a while. So you need to do a "Drive Cycle" on Map 0 so the car can reach "readiness" on Map 0 before you get it inspected. do a google search on what that process is, its not hard to do if you know what is needed (just don't keep flipping maps cuz it keeps resetting the readiness each time you change maps and you will need to start ALL OVER AGAIN). So the short answer to your question is YES

4) Yes, get it. Buy the JB4 + USB Cable + DCI... it will be the best money you ever spent on modding your car. The second best mod will be to ditch the RFT tires and get normal Go Flat Tires!!!!! After that... you should invest in a FMIC, it won't add any power... but it allows you to make the same normal power pull after pull, with the stock FMIC you get heat soaked after the first pull and then you lose a lot of power.

Most thorough post I've seen in a while.

[batman_e92]

Get the jb4 you wont regret it .. one of my injectors failed a month or so after but that has noting to do with the jb4....

+1 for the jb4

[tomchang75]

Thanks for everyone's advice on JB4

[idratherbesurfing]

I have dyno proof I made exactly 100whp gain and 94wtq gain. Its a great tuner and mine is also for sale...message me if you're interested

[DeeDubauWhy]

Originally Posted by Jeff@TopGearSolutions

Most thorough post I've seen in a while.

Second that...and everything stated is a very good beginning point, it was for me and those mods/changes...good stuff here

[BoostedE90]

Originally Posted by DeeDubauWhy

Second that...and everything stated is a very good beginning point, it was for me and those mods/changes...good stuff here

Third that! Nice write-up @fazman!!

[romeojpicasso]

definitely go jb4 you remember that happy face you got when you felt the turbos the hp and tq when driving the car for the first time?


you'll get an even bigger smile when you awaken the sleeping giant