NOT FIRING ON ONE CYLINDER 350i

[dukeenfield]

HI help ,I now got a problem No2 cylinder not firing (run engine when cold for 1 min and the exhaust is still cold).I checked plug and its sparking ok,just wondered how I can check to see if injector is working or not,how to check if its getting any power to it.i have listened with stereoscope and No2 injector does seem to clicking very much,not like the other one's which click quite loud.The engine has also started to make a screeching noise,when I first start it up,but goes off ,after a few minutes

[adam quantrill]

There are a number of possibilities:

1. run with the plug lead on/off - do the revs change?

2. run with the injector lead on/off - ditto.

3. take out the plug - is it wet with petrol?

4. you could try swapping the injector with the cold start one - I think they are all the same. BE CAREFUL
to depressurise the system.

[350matt]

The cold start injector if definitely different to the others,
It does sound like an injector fault, try a can of cleaner in the tank 1st, also check the plug lead and plug on that cylinder. if not a set of 2nd hand injector of e-bay?

[h2dca]

dukeenfield said:

HI help ,I now got a problem No2 cylinder not firing (run engine when cold for 1 min and the exhaust is still cold).I checked plug and its sparking ok,just wondered how I can check to see if injector is working or not,how to check if its getting any power to it.i have listened with stereoscope and No2 injector does seem to clicking very much,not like the other one's which click quite loud.The engine has also started to make a screeching noise,when I first start it up,but goes off ,after a few minutes

screeching noise I would look at this first, maybe just a alternator or PAS belt but would be very cautious about starting the engine if the screech is internal.

>> Edited by h2dca on Thursday 9th December 14:44

[dickymint]

Check for HT lead leakage. Crank her up in the dark and look for stray lightning bolts and ticking
- easy to spot.

[adam quantrill]

Ah - if the injectors are different you could always
swap 2 with 4 and see if the problem moves to 4.

The other thing I forgot to mention is to check for cam lift, you'll have to take off the rocker cover but I think the even side is the easy side. With the cover off crank the engine and check the rockers are moving.

If it ain't getting intake, or not letting out the exhaust, this can lead to poor performance.

[jchase]

You might have lost compression due to all sorts of things, so an engine compression test might be in order.

I had an Alfa v6 running on 5 cylinders and to rectify all I did was disconnect and reconnect the injector plugs - this is not as easy as you might think. (The V6 in question used the exact same Bosch injectors as the RV8 )

-Jim

[dukeenfield]

Thanks for useful imformation,I cleaned the resister plug connections and that seem to do the trick,but if I get any more touble I will try what you said,thanks