Injector not firing

Aussiecsi

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For some reason,#2 injector has stopped working. Yesterday, I was driving at HWY speed and all was well but noticed upon slowing down idle was a bit rough. Subsequently determined it was not firing ....installed another injector and no change. There is continuity/ground from the injector plug and there is spark too . Any thoughts? Cheers, Simon
 

sfdon

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Put the connector onto another injector.
does that injector now not fire?
 

Aussiecsi

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Put the connector onto another injector.
does that injector now not fire?

sorry for delay Don, so here's the latest with #2 cylinder :=

- have established that there is ground/continuity with #2 injector plug ( it fires #1 injector too when substituted for # 1 injector plug as suggested by you )
- there is spark from # 2 ignition lead .
- the # 2 injector appears to be firing ( spark plug was "wet" with fuel when pulled.after running for short period ) .

When the engine was running , we pulled #2 ignition lead and it made no difference to the "idle" . It seems therefore that even though there is fuel and spark, there is no ignition/combustion to #2 cylinder ??

I'm running a 123 distributor .

Hope above info helps . Cheers, Simon
 

adawil2002

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I also run a 123\BMW-6-R-V-IE Switched for 6-cyl. BMW engines with D Jetronic Injection.

Seeing you have continuity at the injector and the plug wire. That leads me to the park plug. I'd replace all 6. If the condition persists I'd suspect the MAP sensor above the brake booster.
 

sfdon

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I suggest a noid light, a compression test, a new distributor cap, a fresh spark plug,and a long screwdriver. But first look in the distributor cap for damage/defect at #2. It’s 4:00 am here so wait til the shop opens here to verify the Bosch2 noid fits the djet connector.
are you using a long screwdriver at your ear to verify the #2 injector is clicking?

 

sfdon

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Aussiecsi

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More thoughts- the wires often fray at the plug to the injector.
make absolute sure the wires are not frayed and touching each other.



#2 and #4 injectors are wired together- if #4 is clicking and #2 is not it is wiring to #2 or injector or injector itself.
you need to hear the injector clicking.

....well Don, didn't bother doing anything after the compression test ...#2 was 45 psi :( ...the other 5 ranged 145-155 .

The cylinder head was reconditioned and i reckon has done < 6,000 km's so hopefully that's still ok. . There have been no overheating issues and if anything car runs very cool . No sign of water in the oil . Head gasket kaput ?
 

Simufly

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....well Don, didn't bother doing anything after the compression test ...#2 was 45 psi :( ...the other 5 ranged 145-155 .

The cylinder head was reconditioned and i reckon has done < 6,000 km's so hopefully that's still ok. . There have been no overheating issues and if anything car runs very cool . No sign of water in the oil . Head gasket kaput ?
I think bugger might be an appropriate adjective!
 

sfdon

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What ever you do - don’t take that head off without doing a leak down test on number 2.
Now is your chance to find out how your rings are doing!
 

sfdon

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Well done. Soon you will be back ready for a good driving season.

spark, fuel, compression rule was right for you!
 

Aussiecsi

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The culprit ,,, burnt exhaust valve
 

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e9john

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Just to help educate me what would be the likely cause of the exhaust valve burning out on a head with under 6000 km on and is that amount of carbon build-up normal ?
 

Aussiecsi

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Just to help educate me what would be the likely cause of the exhaust valve burning out on a head with under 6000 km on and is that amount of carbon build-up normal ?

From what I read, it's possible that the valve was not seated properly and heated gases escaped under compression which in turn burnt the edge of the ''closed''valve..i guess the carbon build up is due to subsequent lack of compression ie inefficient firing . Of course it is likely that I don't know what I'm talking about ....just ask my wife .
 
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