JB4 problem

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Manc M135i
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JB4 problem

Post by Manc M135i » Fri Jun 23, 2017 10:44 pm

Something odd happened tonight...

Switched from map 2 to map 6 and noticed on WOT that it felt rough and the exhaust sounded unusually raspy, engine sounded rough almost like the fueling was all over the place. Switched back to map 2 and problem persisted.

Switched to map 0 and all good, feels super smooth and no raspy noise on WOT.

Rebooted the JB4 software, tried map 2 & 6 and same issue, back to map 0 and running great.

Any suggestions? I'd run a log but it sounds that rough I'm reluctant to give it a full WOT in map 2 & 6 in case somthing goes fizz bang! Is my JB4 fried? I've had it about 4 years!

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Re: JB4 problem

Post by jason@bwchiptune » Fri Jun 23, 2017 10:59 pm

Have you removed it and refitted it ?
Where dose it get the can wires from ?


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Manc M135i
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Re: JB4 problem

Post by Manc M135i » Fri Jun 23, 2017 11:08 pm

Thanks Jason

Haven't removed it, can wires are posi tapped to back of OBD and running latest firmware for a month or so without issue.

Not sure if it would make a difference but I'm running a bottle of fuel injection cleaner that was added to a full tank off Vpower. Can't see it being that though as I'm down to 1/4 tank and I've been running map 2 no issue from a full tank.

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Re: JB4 problem

Post by Blind Pugh » Fri Jun 23, 2017 11:27 pm

How is it in map 1 & 4 ?

If you can log in map 1 and again in map 4 it might give you some clues.

Depending on mileage it might plugs and or coilpacks
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Manc M135i
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Re: JB4 problem

Post by Manc M135i » Fri Jun 23, 2017 11:43 pm

Will try map 1 & 4 tomorrow, if it doesn't feel / sound as rough as 2 & 6 I'll run a log.

Why do you recommend running logs in 1 & 4, lower boost?

I'm 25k mikes, new plugs @ 21k. Idle has been a little rough and also idling at slightly higher rpm's. This is why I ran the injector cleaner through and gave it a good 20 min blast above 4.5k. It's now idling back at 600rpm but still a tad lumpy.

I was actually thinking coils or even a fouled injector but I'm not getting any codes?

How much are coils to replace? Obviously a cheaper place to start ahead of injectors!

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Re: JB4 problem

Post by Manc M135i » Fri Jun 23, 2017 11:59 pm

Looking at symptoms associated to a faulty coil pack I seem to be ticking more than a few boxes.

Rough idle
Sputtering (100% getting this at WOT in map 2 & 6)
Loss of power
Louder rough sounding engine

If it is as coil pack issue, is this possible without codes?

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Re: JB4 problem

Post by Manc M135i » Sat Jun 24, 2017 4:26 pm

Took it out this afternoon in map 0 and running great, switched to map 4 and same rough running issues as last night in map 2 & 6.

Surely this is a JB4 issue rather than a problem with the car?

Would really appreciate and advise?

H

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Re: JB4 problem

Post by rusty13 » Sat Jun 24, 2017 4:52 pm

Manc M135i wrote:
Sat Jun 24, 2017 4:26 pm
Took it out this afternoon in map 0 and running great, switched to map 4 and same rough running issues as last night in map 2 & 6.

Surely this is a JB4 issue rather than a problem with the car?

Would really appreciate and advise?

H
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Re: JB4 problem

Post by Manc M135i » Sun Jun 25, 2017 1:51 pm

Gonna check I all the connections and if it's still the same reach out to BMS.

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Re: JB4 problem

Post by harkes » Sun Jun 25, 2017 3:19 pm

N54tech.com is the go-to place for issues. You can also send Terry an email directly.
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Re: JB4 problem

Post by Blind Pugh » Sun Jun 25, 2017 5:38 pm

Manc M135i wrote:
Thu Jan 01, 1970 5:09 am
Why do you recommend running logs in 1 & 4, lower boost?
Manc

Map 1 can function with or without canbus connected. If map 0 & 1 runs OK it then it means jb4 is OK and it might be more about canbus connection/wires.

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Re: JB4 problem

Post by Manc M135i » Sun Jun 25, 2017 5:51 pm

Thanks BP

I'll try map 1 and see how it runs.

When you say canbus wires, you mean the positap connectections behind the OBD port?

H

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Re: JB4 problem

Post by Manc M135i » Sun Jun 25, 2017 7:45 pm

Just tried map 1 and get the same issue as all the other maps. :?

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Re: JB4 problem

Post by Blind Pugh » Sun Jun 25, 2017 10:14 pm

Manc

As per Harkes post above - contact BMS for support as it reads like a problem with jb4.

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Re: JB4 problem

Post by Manc M135i » Mon Jun 26, 2017 12:47 am

I've connected with Steve at BMS and explained the issue, he's asked for a log to help diagnose.

I'll run one tomorrow, just a bit reluctant to put the car through a full WOT across the rev range when it's missing so violently. Scared of somthing going pop! :-/

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