350i misfire

[bin looney]

i have fitted a new valley gasket thus having to remove manifold and wiring.
it leaked so i did it again and now it has a misfire.
everything is back in its place, replaced leads and checked plugs, still the same.
any ideas.

[chassis 33]

Hi, no science here, just some things to check....

When you took the top hose off the manifold, did any coolant get into the dizzy housing?
Are there any air leaks around the plenum/trumpet base or the hoses? Spray WD40 into the mating faces, if things improve you've found the leak
Did you knock any of the adjustments, eg on te air flow meter, unlikely but possible
Are all the connectors home fully? The lead to the AFM on my racer has a habit of jumping off so it's zip tied on for security now.

Give us a bit more of a clue, what sort of mis-fire is it? Across the rev range or just a certain revs? On acelleration or cruising? Etc

Regards
Iain

[bin looney]

cheers mate.
ticks over fine, just misfire constantly across the range.
i will check the things you have said must be something i have done though.

[bin looney]

accelerating not cruising

[jchase]

I had a similar problem after replacing head gaskets and valley gasket - Turned out to be the little plastic thingy in the vacuum advance line - I removed it, and it ran great. It maybe that the misfiring you got closed up the leak port inside it. It is supposed to react slowly to increases in manifold vacuum, but quickly to decreases, so it should be a leaky one-way valve. I used Hermatite green on the water passages in the valley gasket, and hermatite red on the oil seals, and hermatite blue on the plenum seal. So far no leaks.

-Jim

[bin looney]

sorted it was just a loose connection on one of the injectors under the air hose.
went out in it at 9 oclock roof down FANTASTIC.
cheers all.

[chassis 33]

Result.

In my very very steep learning curve in this first season racing, I am beginning to learn more and more that big things very rarely go wrong, it's always nit sh1t that knocks you over and is blindingly obvious after the event!!!

Regards
Iain

[bin looney]

are you racing a wedge? and in what series.
i have the 350i for pleasure although its mixed in with head scrathing and scuffed knuckles.
i have a Triumph TR7 V8 also that i do track days in, big fun.
i have a 3.9 i am readying to go in so buckets of fun if it all works out.

had another drama today i had tie wrapped the cable near the steering column and the bolt on the steering column caught on it knocking half my electrics out, my stupid fault but thats how you learn i guess.
cheers.

[chassis 33]

No, I race a Chimaera in the Tuscan Challenge, plenty of Wedges in with us though. My Wedge seems to be a permenant piece of scenery in the yard that never quite makes it to the top of the to do list.

Regards
Iain

[tallbloke]

bin looney said:

had another drama today i had tie wrapped the cable near the steering column and the bolt on the steering column caught on it knocking half my electrics out, my stupid fault but thats how you learn i guess.
cheers.

Been there and dobe that. Careful tiewrapping and a bit of limbo dancing undeer the dash to sort it properly.