Intake Manifold Leak?

[260Zed]

Gday, I just wanna run this past everyone to make sure my thinking is correct. Cylinder No5 doesnt make a difference when i pull the spark lead. when i check the plug its wet with fuel. I've checked plugs and leads and dizzy rotor. When its chugging away on 5 and i spray carb cleaner around the intake the miss goes away.

So ive got a manifold leak.

This only appeared out of the blue, I just finished wiring a rx7 fuel pump. I tested the pump on the car ran great. Wired it up so as to stop when engine dies. Then after that I started her up i started to get the got problem. I'm SURE the pump isnt the cause.

Manifold gasket is prolly only 4-5 months old (The exhaust place is like "nah get no problems with these gaskets" when enquired about it when i got extractors fitted)

So can a manifold leak prevent the firing of the cylinder?

Can it just sorta happen suddenly like that?

Is a 75 260Z Dome top Su's, 280zx dizzy and coil, mild cam, extractors with 2.25 exhaust. As of 3 weeks ago compression was an even 150 on all cylinders with throttle open.

Thanks for the opinions everyone

Luke

[MicksZ]

sounds like if they spark plug isnt firing and is wet hen u pull it out, the plug might be stuffed. How old are the plugs? Might be a good time to replace them ALL anyways now cos they arent too expensive.

Sounds like plugs OR Leads to me...

[MicksZ]

I just re-read my post - my english is bloody shocking! hmm....

If you are running carbs, and only one cylinder isnt firing, i think it is has a stuffed plug and might be running a bit rich which is wetting the plug (as you said) and thus not firing the plug.

As i rambled on about, replace all the plugs and see how you go.

Will work on my english..