BMW E90 N43 MSD80/81 repair - no injection (injectors internal fault)

[@andyapple9]

I would search for an equivalent mosfet with the same packege, also on this kind of replacements it's recommended that you replace all mosfets that drive the fuel injectors.

[@vadimgajiu4844]

Good evening, I have a request for you, can you help me with some advice. And so I have a BMW 320i 2008 engine n43b20a on diagnostics it shows that there is a problem in the second cylinder, they changed the injectors, they changed the coils, it didn't give anything, they thought that the gbc gasket was punctured, they measured 1-2 cylinders, everything is fine, 13 atmospheres, could the cause be in the brain? If so, how to change it and do I need to pour new firmware into a new block??

[@gcauto6946]

Hello, what reference do the replacement Mosfets have? 

[@autodiagobd]

Irf644b

[@gcauto6946]

Thank you!

[@paweg4643]

​​@@autodiagobd mosfets should't be 250V you need 300V. I recomend fdb14n30tm it's more expensive but proper for this DME.

[@Kaan5410]

​@@paweg4643would it be okay if i switch only one Mosfet which you recommended or should i switch all irf6442 to fdb14n30tm?

[@NYPDGermany]

@@Kaan5410hepsini yap

[@theautomotiveclinic3582]

Awsome mate 👍👍

[@2Pacmixes]

You don't need to replace all injectors surely??

[@4642mati]

Super

[@muhammedsubhi2082]

Good work ❤

[@karerodfjell]

Where do you buy low melt solder?

[@autodiagobd]

From China.

[@akramsha970]

Thanks

[@CATA20034]

Stop messing with low melt solder on the autotmotive stuff. You are contaminating the pads. As a HW dev in automotive, I can tell you that during some short circuit, if the prottection trips late, the fets are almost desoldering by itself with standard solder. With your low melt solder, on the next overload, those mosfet can move on the pads or even fall. Use some cutters to cut off the gate and source and unsolder them individually, so you don't stress the pads too much with only one solder iron. I usually use a 120-160W sodler iron with flat tip so it's fast on the thermal transfer.

[@xConundrumx]

Finally some common sense. Dodgy testing of mosfets aside (as seen in some videos) ... yes ... cut the dang legs and stop cooking the board if it isn't needed.