[T3] missing on cylinders #2 & #3 FI 72 Fastback

[Jim Adney]

On 10 Jan 2012 at 16:05, Vern Creamer wrote:

> Newbie lurker joining the fray.  I have already learned a lot from
> this group. 

Nice to hear a new voice, Vern. Welcome to the Type 3 email list.

> Had the engine out last week for clutch repair; installed new spark
> plugs while the engine was out.  Ran terrifically for the first 100
> miles or so, smoother than ever.  Over the last 50 miles, it's been
> missing as I rev up each gear; sometimes, it gets somewhat smoother
> once I get over 50 or so. 

What year? Carbs or FI?

Oh, I see it's in your subject line: '72 FI. Okay

> So far, I've replaced the (brand new) spark plugs ... #1 & #4 looked
> perfect; #2 & #3 are fouled black ... all of this after just 150
> miles.  When running, all 4 plug wires spark when loose but held close
> to the distributor.  When I back #1 & #4 away, the engine begins to
> stall; when I back #2 & #3 away, there is no change to the engine. 

So 2 & 3 aren't getting fuel, or they're getting too much fuel.

> The next thing I'll check are the plug wires; after that, not sure
> which direction to go.  Suggestions? 

Check the wires at the multi-point ground at the top center of the 
engine. Make sure one of them hasn't come loose, or has broken.  

Check the wires under the injector boots. Make sure that one of them 
has not broken and is now shorting to the other one.

You didn't, by any chance, forget to install the pressure sensor 
hose, did you?

-- 
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Jim Adney, jadney at vwtype3.org
Madison, Wisconsin, USA
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