[HouseN54]

what part number did you use to replace mosfets?

[RyanF82]

Originally Posted by HouseN54

what part number did you use to replace mosfets?

I used these ones - http://www.mouser.com/Search/Product...844-IRF644SPBF

But I don't think it has anything to do with the mosfets either since the ones that I replaced all tested okay. I believe it's a fuse or loose connection somewhere, but I just have no clue where to look for it at. I tried checking all of the fuses that I could find, but they were all good. I know I've seen pictures and read about people having the exact same issue caused by some of the fuses in the DME box blowing, but I don't have those fuses in my DME box. I'm assuming that particular fuse box is located somewhere else, but I'm just not sure where to find it.

[andydna15]

Are there any bent pins in the ecu or any connectors that are loose? I know there's a green connector that provides power , have you checked that also ?

[musc]

Did you replace the MOSFETs from the DIY found on this forum? There are a bunch of different ones in there. I know it sounds dumb but I would make sure the right thing was replaced. I have had 3 friends just replace the single MOSFET that failed along with the coil and plug and the code never came back.

[Maxnjana]

RyanS13,

Did you get this fixed? If so, what was the issue. I am having a similar issue without the 30BB code.

[HouseN54]

Sometimes when the MOSFET goes it will take a coil or injector with it, in rare cases both.

[08335ibmw]

Im having this issue with 4, 5 ,6 and 30bb any solution to this problem . Im going to look into the mosfets

[muncie21]

You may also want to consider moving the injectors around and possibly replacing the plugs.

When my #3 injector went out, I was throwing codes for cylinder 1-3 misfire. I started by trying to determine what could impact all the cylinders at once (mosfets) in the end it was a single injector that was causing all three cylinders to report misfires.

[Dreezyjuice08]

Anyone have this problem ?? Mosfets appear good but still have the 30bb code ?

[fedejunin]

Originally Posted by Dreezyjuice08

Anyone have this problem ?? Mosfets appear good but still have the 30bb code ?

Same problem. Code 30BB, I replaced all the mosfets, then code can’t be deleted. I followed a tutorial where they disconnect the injectors wires and coils wires as well, if the code persists, so it is the DME or the wires. I checked the wires with a ohmnimeter and the wires were fine. I checked the grounds of the injectors, were fine.
So, my last thought is that the problem may be the DME itself.

[hi_swerve]

I had the 30BA code... upgraded to MSD81 & problem solved. Had new coils & plugs already in there, and upgraded to new index 12s as preventative maintenance.

[Momogord]

Originally Posted by fedejunin

Same problem. Code 30BB, I replaced all the mosfets, then code can’t be deleted. I followed a tutorial where they disconnect the injectors wires and coils wires as well, if the code persists, so it is the DME or the wires. I checked the wires with a ohmnimeter and the wires were fine. I checked the grounds of the injectors, were fine.
So, my last thought is that the problem may be the DME itself.

Did you end up finding the root cause for your issue ?

I have kind of the same problem. Have checked the MOSFET and they are all fine. Then unplugged the injector #1 and the 30BB code would clear and car would run on 5 cylinders. I thought I had a bad injector so put another one in place but still have the issue. 30BB code and misfiring on cylinders 1-2-3.

I do not have an idea beside a ground somewhere.

[veeldz]

Originally Posted by Momogord

Did you end up finding the root cause for your issue ?

Same questions... Anyone solved the issue other way than replacing whole ECU?

[tello2020]

Originally Posted by muncie21

You may also want to consider moving the injectors around and possibly replacing the plugs.

When my #3 injector went out, I was throwing codes for cylinder 1-3 misfire. I started by trying to determine what could impact all the cylinders at once (mosfets) in the end it was a single injector that was causing all three cylinders to report misfires.

hello I have the same problem with my car misfiring cylinder 1 2 3
change spark coils replace the dme mosfets just in case and move the injectors from 4 5 6
to 1 2 3 but still the same how did find you out was your injector # 3 bad ?
Thanks,

[tello2020]

hello any update on this issue, any one fixed,

[Cuda021312]

Hi everyone. Just wondering if anyone has fixed this issue. I replaced the mosfets and all check out fine. Installed ecu and was running fine for a short time and now I'm getting code 30bb. I took the injectors out and cleaned them as #4 had quite the carbon build up. Reinstalled but same issue persists. I had no ignition codes present so I swapped coil#1 with coil#4 and same problem. Swapped coils back and now coil#1 is out and code is present.

I'm going to change all coils and plugs and go from there. If that doesn't solve it, the injectors next and that leaves the ecu last.

If anyone has any advice/input, I'd be very grateful! Thank you!

[DRaven13]

In a similar situation with my Son’s ‘08 convertible (134k miles). Misfire codes for cylinders 1-2-3. Occasional “Too lean Bank 1” code. Fuel trims on Bank 1 in the high 20s to low 30s. The upstream O2 sensor on Bank 1 is 3x what the Bank 2 sensor reads.

With out doing any research on the issue we swapped in new coils and plugs assuming it was just a tune up issue. No change.

Then we pulled and cleaned all of the injectors. No change.

Moved injectors from front to back (Bank 1-2) one at a time to isolate the bad injector. No Change.

Ordered a cable and INPA. Should arrive Wednesday. Does anyone have an injector laying around we can test with? With all the issues with MOSFETs on the DME; I am hesitant to use a test light on the injector leads.

Does limp home cut the same cylinders or is it dependent on the codes throw? Pulled the plugs again to see what is happening in the engine only to find 1 and 2 seem dead and 3-6 are all sorted up and pig rich.

Baffling!

[tello2020]

Anyone solved this issue ?
Misfiring cylinder 1 2 3

[juham]

any ideas? i have same problem n43b20

[RyanF82]

Just to give an update on how I fixed the problem back when I originally started this thread years ago...

I went through everything I could and still had the same issue, so I gave up and had the car towed to an independent shop for them to work on it.

I drop the car off, and I go to eat at a fast-food place in the area with my brother. We're sitting down eating next to the windows and I look out and see my car going down the street.

Got a call from the shop a few minutes later saying everything was all good, the code was gone, and the car was running fine now. The only thing the shop did that I never tried... uninstall my Cobb Accessport tune from the car.

So I don't know what happened with the tune, but for some reason, something got messed up and wouldn't run correctly anymore, and started throwing the 30BB code. Once the Accessport was completely uninstalled, the car was fine with no codes. I reinstalled the Accessport after picking the car up and it was fine from that day on, never had an issue with it again.

Probably might not be much help to the others who are having this issue, but this was my experience.

[antoniog]

I have recently had the same 30bb code and the mosfets were good.
Upgraded to msd81 and 30bb is gone now...

[Zekerbox]

I'm running into this issue after installing new index 12 injectors. I have codes for both banks 30BB and 30AA. I already have an MSD81, new coils and new plugs. Is there a way to "reset" the DME? I'm stumped