[T3] Cylinder Performance

[Adriel Rowley]

----------------------------------------
> From: jadney at vwtype3.org
> To: type3 at vwtype3.org
> Date: Tue, 21 Jun 2011 20:18:19 -0500
> Subject: Re: [T3] Cylinder Performance
>
> On 21 Jun 2011 at 16:01, Adriel Rowley wrote:
>
> > Finally made it out to the Squareback; work has been unpredictable.
> > Installed the rebuilt spark plug wires and installed nicer than the
> > new ones.  They fit better in the holders and are tighter on the cap.
> > Only concern was number one was a stretch.  They should be loose
> > right?  Adney, can you do anything about this?
>
> Odd that it would be short, but Bosch may have just gotten their
> lengths wrong. Nice thing about the OE style sets is that you can
> replace just the wire. Next time you need something else I can throw
> in an appropriate length of wire if you can tell me how much you
> need.
>
My new ones were fine in length.  I think it was just an accident, as it 
was about the length of the new's number three. ;)

Looks like a deal, especially if it comes with instructions. ;)  Be good, 
as the length can be used elsewhere or as a spare. ;)

> > Only thing was it was hard to get it up to 50 M.P.H. as it run out of
> > power to do it.  When coming back was able to persuade it up to 53
> > M.P.H. but took feathering the throttle.  This reminded my I had not
> > checked the T.V.S..  When I got back, I tested it, which was a bit of
> > a challenge with the warm engine.  Idle circuit shows 0 Ohms along
> > with the fourth test, and the second and third tests get odd results.
> > Seems that might be my problem?
>
> The TVS is NEVER the cause of poor power. I don't know how this got
> started, but for the last couple years it's been getting a lot of
> unwarranted attention. If you think your TVS is bad or unadjusted,
> just unplug it and see if your engine now runs better. If you don't
> notice an improvement reconnect it and move on.
>
Then where did the idea come from?  Or, one of those with no backing...

> > Anyone have an extra four pin T.V.S.?  Been using a five, but switched to this four pin thinking it worked; now need to remember where I put it.
>
> A 5-pin is never an appropriate replacement for a 4-pin. That just
> doesn't work. If you have your original 4-pin it is probably fine.
> I've seen worn out 5-pins, but never a worn out 4-pin.
>
We have been down this road.  I used it for quite awhile, along with 
others, so not sure of the validation of that id does not work. ;|

I am confused then with this statement: "If you see any sign of 
decreased resistance anywhere in the travel of the throttle, your TVS 
may be worn out."  So, I guess I do not understand the instructions 
clearly as all I want to do is check adjustment, not set it.

"[...]slowly turn the TVS CCW until the VOM jumps from high to low 
resistance."  "Make sure the VOM goes to low resistance every time 
the pedal comes back to the idle position."  So, why do I have no 
resistance and no change in resistance, i.e. always 0 Ohms?

"Connect your VOM across the 2nd and 3rd pin of the TVS. Slowly open 
the throttle. You should see the VOM change from high to low 
resistance several times as the throttle opens but not as it closes. 
Repeat this test with the VOM connected to the 2nd and 4th pin."

I got this to some degree, but no not recall for sure that I got 0 
ohms when closing.

"Finally, set your VOM to its highest resistance scale and connect it 
across the 2 bottom pins of the TVS. Slowly open and close the 
throttle several times while you watch the VOM. If you see any sign of 
decreased resistance anywhere in the travel of the throttle, your TVS 
may be worn out."

This one got all sorts of strange readings.

> Of course it's possible that your 4-pin was damaged by someone who
> damaged it internally. That certainly happens, but there's no excuse
> for it.
>
I believe I opened this one up, and all looked fine.  I open them to 
set the adjustment according to another fellows method, but wanted to 
compare the results. ;)  As in all parts of my life, I do not take 
sides, but take what I know is truth and combine to make my conclusion.
;)

So since I am chasing nothing, what should I be?  Fuel, air, and spark
is what is needed to have an engine run.  

Air: valves were recently checked/adjusted, and have about 3,000 miles 
on them, so rarely need much adjusting.  Oil in the air bath was 
recently changed.  Air also coming in through the plenem, as evident
when the 3/4 runner was off.  Compression is good.

Fuel: Last check pressure was 28 to 29 p.s.i..  Fuel injectors are 
injecting fuel on the 3/4 side;1/2 unknown but have not shown any 
problems.  Fuel is fresh, proper octane, and with addictive.

Spark:  Engine was recently timed.  Plugs are cleaned and gapped. I
can see if I have another set if you think I need to change them.
Distributor was rebuilt by Adney, and is firmly in place.


Thank you so very much!
Adriel