M20 only firing on five cylinders!

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Finny
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Post Thu Apr 20, 2006 8:34 pm

I have recently transplanted a m20 325i lump into my 316i touring.

The problem is that now installed and running it is not firing on cylinder 6 the one nearest the bulk head. i have checked to see if the iginition side of things is ok by turning the engine over with the sparkplugs sitting on the rocker cover and they all appear to be sparking ok.

When i replace all of the plugs and fire it up it only runs on five and plug number six is black and soaked in petrol.

Any one got any ideas??? Could it be a sticking valve or something?

Its doing my head in because this is all that is stopping my new project from being on the road!!!!

Any help will be greatly appriciated.

Cheers

Mark
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georob
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Post Thu Apr 20, 2006 9:50 pm

number 6 injector knacked or dirty, take it out, give it a clean out with brake cleaner and some air

worked the trick for me, had xactly the same prob

all fine now
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Finny
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Post Thu Apr 20, 2006 10:04 pm

Plug is wet with petrol so surely the injector must be workin ok?
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georob
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Post Thu Apr 20, 2006 11:00 pm

No, the other injectors will compensate for the blockage resulting in more getting pumped through, is your mpg poor also?

theres a guide how to do it on pelican, you dont need to take off the inlet manifold either, takes about ten mins to remove, 15mins to clean and ten to put back together

i tried everything and it turned out to be that

let me know how you get on
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Finny
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Post Thu Apr 20, 2006 11:26 pm

Dont know bout mpg i havent really ran it for any distance because its a bit dodgy.

all of the other cylinders are fine with no overfuleing in them.

So are you saying that if the injector is blocked it could actually lead to overfueling in that cylinder? because like i said their is fuel in the cylinder which is not firing.

Whats this pellican thing?

Cheers
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georob
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Post Thu Apr 20, 2006 11:33 pm

Yeah, thats what happened to mine, ended up getting rac out to check it, guy advised injector

i followed the guide on this

http://www.pelicanparts.com/BMW/techart ... h_main.htm

and bingo, running sweet as now
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georob
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Post Thu Apr 20, 2006 11:36 pm

sorry, meant to say, no, not overfuelling in that cylinder, the injectors that were working fine on mine was where the plugs were getting sooted up from
Templ8e30
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Post Fri Apr 21, 2006 9:28 am

Number 6 injector is probably leaking giving much more fuel than the others.

I'd either get another injector or have it ultrasonically cleaned or get the lot ultrasonically cleaned and the flow rates matched.

Cheers,

Iain T
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