Miss on #6

[MNSubbie]

I have a pronounced miss on #6 Cyl in my 2000 Blazer. 155K Miles. Has great compression on all cylinders. I just put in all new plugs and the plug wires look great. Distr Cap looks good inside and out with no carbon tracks. Am I looking at an Intake leak??? Or might there be something else over near #6 that could cause that cyl to be so weak? Any/all advice or ideas would be appreciated.

[MT-2500]

Originally Posted by MNSubbie

I have a pronounced miss on #6 Cyl in my 2000 Blazer. 155K Miles. Has great compression on all cylinders. I just put in all new plugs and the plug wires look great. Distr Cap looks good inside and out with no carbon tracks. Am I looking at an Intake leak??? Or might there be something else over near #6 that could cause that cyl to be so weak? Any/all advice or ideas would be appreciated.

Is it a dead miss or just part time?
Can you feel miss on the road?

You can not tell if cap and wires are good by looking at them.
What engine and engine code and new or old syyle dist cap?
Always us AC delco plugs and cap and rotor and good brand of wires on a tune up.
Check for good hot blue spark from coil and to the spark plugs.
Make sure fuel pressure is up to par and also camshaft retard setting is close to 0 degrees - or +.
Any engine check egine light or codes?

[MNSubbie]

Thanks for your wilingness to help, MT. Here is some add'l info:
*Engine code is W (8th digit in VIN, right?)
*Dead Miss all the time, which is felt less as the rpm's increase. Engine has reduced power at all rpm's
*Have the small, flat distr cap which is only about 3 tall and has the wires coming out parallel with top of cap, 3 on each side. Believe cap and wires are all original.
*Plugs I just took out weren't that old. 1,3,5 plugs looks beautifully clean with white porcelain. 2,4,6 had some browninsh areas on the procelain, and the plug for #6 had a very definite black stain on the porcelain. New plugs are AC 41-993, and i do have a nice steady blue-white spark, right down by the plug
*Do have ECM Code 306. After I reset it, the code comes back within seconds of starting the car.
*Unless someone points me in a different direction, my next step is a vacuum test, and maybe spraying some starter fluid around the intake gasket areas

What am I missing here?? Thanks in advance for your continued help

[MT-2500]

Yes on 8 digit.
I just had a olds bravada crossgfires and missing.
Cap and rotor looked good.
Replaced cap and rotor and it ran good.
Replace dist cap and rotor with AC delco parts.
Replace wires with a good brand wires.
Check camshaft retard and fuel pressure.
If you alredy have new plugs switch one with the plug on missing cylinder.
And see if miss moves.