82 2.0L A/C 'Hwy Speed Only' Shudder

[82WestyMan]

Thought I’d run this past the AirCooled Bay Window crowd ‘cuz I’m stumped and most of the Vanagona WBX'ers aren't really a help... and I'm a diehard aircool fan

I have the most particular problem with my 82 2.0L Wesfalia. When I’ve been at hwy speed (60-65mph) for about 10 miles or so, I start to get a shudder in the power, very slightly, like its momentarily starved for fuel or there’s a momentary glitch in the ignition.

Now here’s the rub. I’ve read all the usual threads about what could be the cause in the fuel system or the ignition but:

The fuel system is new… and I mean completely new: Tank, tank seals, evap lines, square filter (before pump), BD fuel pump (http://busdepot.com/details.jsp?partnumber=043906091), big round Bosch filter (after pump), reman injectors, cold start valve, pressure regulator and 7mm braid cloth covered fuel line (http://www.germansupply.com/home/customer/product.php?productid=16135&cat=334&page=1)

The ignition side about same… completely new: real Bosch ‘blue’ coil, new spark plug wires (with the extra long coil/cap wire), Bosch Platinum Plus spark plugs (4035), Bosch cap and rotor and a Pertronix ‘Breaker-Less” ignition modual (1847V)

The other day, I pulled of the interstate right up to a long red light and watched my tack cycle from idle (800-900 rpm) down to nearly stall then back up (and yes, I gave it a bit of gas to make sure it wouldn’t) until the light turned and I drove off at 40-45 and the problem went away.

HELP!!! … am I just having a ‘brain fart’ and missing something obvious? I really need to get this fixed for a couple of reasons: between now and summer there are a couple SE VW shows I want to go to that are about 200-300 mi away, but WAY MORE IMPORTANT, I about have my boss taked into letting me off for 4 wks at the start of summer and I want to head out the Southwest and do the grand tour of the National Parks... and this problem would drive me crazy over the course of 4 wks and 4-5K miles

About my only thoughts at this point are: replacing the 7mm german fuel hose with 5/16” (7.9mm) rubber FI hose from the local FLAPS and put another small square filter between the tank and pump (just on general principals)

PS - I know what I forgot to include in the above...
I've done the 'sand and clean' of all the grounds... everyone I could find in the engine compartment, the ground strap between trans & body and in the battery compartment.
Haven't done the ones behind the fuse panel, that coming up when I put the new brake booster / master cyl this month
And all the vacuum lines are new too
_________________
"The floggings will continue until morale improves"
"I never did give anybody hell. I just told the truth and they thought it was hell" - Harry S. Truman
82 Westfalia - w/ a Raby 'Camper Special' engine

[1975 Kombi]

Have you checked the condition of the plugs to see how the burn is. Rich/lean.
_________________
Brett

“He’s decieving you boy! Reach into his pocket and take what he’s got.” Mr. Crabbs.

75 Westy auto
03 Jetta TDI
71 SB
74 Westy
Licensed pilot (single engine land VFR)
--
Rust In Pieces: 72 Bug, 73 Bug, 81 Rabbit LS D 2D, 83 Rabbit D 2D, 84 Jetta TD GL, 85 Jetta D, 68 Z28 RS 302, 91 Passat 16v

[busdaddy]

You may want to try a set of copper plugs in there and see what difference they make.
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Rust NEVER sleeps and stock never goes out of style.

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[mightyart]

Yea, get rid of the plugs, put in regular Bosch
How new is the AFM?
Have you checked the tracks on it?
Make sure the arm is moving freely.
Another thing to remember is just because the parts are new doesn't mean they can't fail, or be bad when you get them.
Did you ever buy something new from the store, take it out of the box, and then have to take it back for an exchange cause it wasn't working right?
The same principle applies to car parts.

[towd]

I go along with get rid of the Bosch Platinum plugs,, they have a very bad rep ,, even in Hondas..
The plugs are not causing the problem,,, I've never had them last long before fouling..

So I just won't use them in my air coled motors