[jamhot]

Hey guys. I had an injector go the other week. after checking I realised I had index 1 across all so decided to do the full replace for index 12 and recode them upon installation. The car ran fine up to the point of failure and no rear start up issues apart from a slight spit from the exhaust on cold start, I always put that down to the excess fuel for the cold cycle. Now that I have installed index 12, the car seems to struggle on start up. it starts quick but stumbles and bogs until i give it a bit of throttle. It seems to level out and idle fine after that. But my biggest issue which i believe must be related is that the car had been throwing me boost under target and then on a different occasion, an overboost???!!! As I say, the car ran fine up to the point of changing the injectors. Have I missed anything that should be done in addition to the coding?

TIA guys

Dan

[Wolf 335]

- First thing go back and inspect that all electrical plugs are in fact plugged and seated properly in the injectors.

- Make sure injectors are seated in their slots properly and that all grounding wires are attached.

- Pull all spark plugs and inspect for wear and/or oil

- Check for valve cover gasket leaks

- It is possible that during the injector replacement maybe you have damaged one of the vacuum lines.


Good luck and keep us updated with your findings.

[jamhot]

All checked and took my time doing everything very carefully. Pretty sure nothing has been upset while changing them. All my vac lines have been replaced with decent silicone not long ago and my plugs done about 2k ago, while my old injectors were in place. I've also had the turbo flaps re manufacturered because of boost issues, which solved the problem.

[jamhot]

Took this log earlier. Looks like it running rich? Although the boost issue doesn't seem to show http://www.datazap.me/u/jamhot/log-1...ta=1-3-4-18-24

[MysticRob]

Everything else being good, double check your coding #s (ensure the DME took them and kept them properly in order), ensure the seals and decouplers are good, and above all, recheck the plugs for gas smell because even though you're using new -12 injectors, it's possible one or more were bad out of the box.

Since the car was running badly prior to the injector change, so it's also possible the injectors aren't the only issue. Coils could be going out, plugs might be fouled after 2k miles and bad upstream components, etc. Recheck everything and let us know what you find.

[335e92tx]

HPFP failed right after injs replaced..

[jamhot]

@ 335e92tx You mean that happened to you?

[335e92tx]

yep. Had cold start rough idle - would last 30 secs. Replaced all 6 and was good for about 4 days and then started again.. not exactly long cranks.. but still sour for the first few secs.. then clean out.

Ended up being the 4th fuel pump

[jamhot]

did you get any codes to support it? specific to fuel pressure

[335e92tx]

There were high pressure errors. along with cyl misfires...

ymmv

[jamhot]

ok guys I found the problem. Not that I suspected it at all but 2 of the new injectors were leaking ! I ran a log at idle for a while and noticed that bank 2 afr kept fluctuating about 0.5 on the scale. So i pulled cyl 456 injects and connected them to the fuel lines above the engine without the trigger cables and turned the engine over. two of them started to spray out at right angled to the head. So I fitted the old injectors I knew that still worked back in, re coded them and boom, all good with no rough idle and starts.

[Boland01]

That doesn't say much for the mfg's quality control. Glad you found the problem.

[totti84]

Were the -12 injectors brand new OEM?

[AWDBooSTIn90]

MOSFET'S in DME for the injector drivers? Or is that problem for the coil pack ground outputs?

The reason i bring this up is bc I see you have a '07 335i, which has the MSD80 DME.

They are known to have issues with the MOSFET'S going bad. Theyre soldered directly onto the circuit board itself. If this was the issue, you could order the correct MOSFET'S online and have a local TV/electronics repair shop, unsolder the old one's & solder the new one's back on.

However they can be replaced for not too much $...

I didnt look on the logs bc im on my phone, so i cant comment on the hpfp. But does the pressure reading stay steady and rise under boost? Also watch the lpfp for the same scenario..

Just curious, how many miles are on the car now? Im curious to see how long the Index-1 Injector's lasted.

Has the HPFP ever been replaced yet?


Hope you can get it figured out qucikly..