M50 injector + MarkD chip won't start

[e34_spangler]

You tried hitting the fuel pump if you hit it while trting to start the car you know your fuel pump is bad

[harold30]

You tried hitting the fuel pump if you hit it while trting to start the car you know your fuel pump is bad

pump is relatively new and no issue with stock injectors.

is 9 volts battery enough to test injectors?

[e34_spangler]

Might as well check the pump though I've bought brand new parts from bmw and have had them not work

[harold30]

Update:

Today I tested which injector is not firing.

So what I did was pull the fuel rail with the injectors in tuck, put some small cloth underneath each of them and start the car. The area of the cloth where not wet and no smell of fuel means the injector is not firing. After identifying the defective injector, I removed it and shot it with WD-40 and installed it back and did the tap trick. Put everything back together and start the car, voila it works!

Idle at 700-750 rpm and drops after pressing the gas pedal but it will back to normal (ecu still learning)

It feels good when you hear the engine smooths out...

Thanks everyone for your reply and suggestions. I really appreciate them all.

Cheers!

[CabbE30]

Sweet! How are you liking the chip?

[603Racing]

You really should clean all the injectors and replace all the seals when swapping them. Otherwise you're just asking for trouble. There are threads the cleaning process. Dirty injectors (and they aren't clean if at least one was sticking) won't provide any performance gains.

[harold30]

Sweet! How are you liking the chip?

I can't say much about the chip yet. Haven't drive the car long enough.

You really should clean all the injectors and replace all the seals when swapping them. Otherwise you're just asking for trouble. There are threads the cleaning process. Dirty injectors (and they aren't clean if at least one was sticking) won't provide any performance gains.

Bought a rebuilt injectors ;)

[603Racing]

Were they cleaned or just have new seals? If they were cleaned (properly) they shouldn't stick... unless they sat for a long time... in which case they probably should have been cleaned again.

I'm not knocking you or anyone that may have sold you the injectors, but if I were to put the time and money into a chip and injectors I would make sure they were 100%. Otherwise you're cheating yourself.

[harold30]

Were they cleaned or just have new seals? If they were cleaned (properly) they shouldn't stick... unless they sat for a long time... in which case they probably should have been cleaned again.

I'm not knocking you or anyone that may have sold you the injectors, but if I were to put the time and money into a chip and injectors I would make sure they were 100%. Otherwise you're cheating yourself.

They were flow tested, ultrasonic bath, cleaned and new orings and pintle caps (IIRC) those were from maksinjection.com. I'm from half way around the world and travel period would take 2-3 weeks and humidity will change too. So I guess that explains it. But anyhow, I'll take your advise. Thanks!

[603Racing]

2-3 weeks is no big deal. Might have just been a freak thing. Or perhaps a short on the injector connection... who knows. Sounds like you're good to go now.