Piston Slap: The Vanagon's a Little Rough Around the Edges?

Sajeev Mehta
by Sajeev Mehta

TTAC’s very own David Holzman writes:

Sajeev,

My friend Polly’s ’83 air cooled, fuel injected, VW Vanagon dies at stoplights, and she has to let it cool down before it will start again. It also runs a bit rough, and it’s normally hard to start.

The engine was rebuilt 5 years ago (in Sturgis, South Dakota, where she’d gone from her home in Bethesda Maryland, for a sheepdog trial, by a VW mechanic whom she rousted out of retirement), and she thinks she’s put less than 20k on the clock since. In efforts to solve the problem, the air flow meter, the wiring, and the spark plugs have been replaced.

Any ideas? Thanks!

Sajeev replies:

In these cases, I go back to a couple of fundamentals of the internal combustion engine: fuel and spark. One of them is misbehaving. I am far from a Vanagon-guru, so let’s discuss the common test points for any EFI system.

Fuel is pretty simple to test: a fuel pressure gauge is mandatory for EFI controlled cars. Depending on the manufacturer, a fuel injected vehicle needs anywhere from 10-40psi of pressure to keep the motor happy in any temperature, any driving condition. If the Vanagon’s fuel system is out of spec, test the pressure regulator (normally that means blocking off the return line, but I can’t comment specifically on this application) and the fuel pump.

But I suspect it’s the other part of the equation: ignition. From start up to full throttle, heat is an ignition system’s deadly enemy. I‘d check the Vanagon’s baseline ignition timing (and whatever timing advance mechanisms exist on the distributor) the resistance of the coil and maybe the ignition module. Shouldn’t be too difficult for a VW whiz, and hopefully the cheapest part is the only problem.

(Send your queries to mehta@ttac.com)

Sajeev Mehta
Sajeev Mehta

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  • Socrates77 They're pinching pennies for the investors like always, greed has turned GM into a joke of an old corporate American greed.
  • Analoggrotto looking at this takes me right back to the year when “CD-ROM” first entered public lexicon
  • Alan My comment just went into the cloud.I do believe its up to the workers and I also see some simplistic comments against unionisation. Most of these are driven by fear and insecurity, an atypical conservative trait.The US for a so called modern and wealthy country has poor industrial relation practices with little protection for the worker, so maybe unionisation will advance the US to a genuine modern nation that looks after its workers well being, standard of living, health and education.Determining pay is measured using skill level, training level and risk associated with the job. So, you can have a low skilled job with high risk and receive a good pay, or have a job with lots of training and the pay is so-so.Another issue is viability of a business. If you have a hot dog stall and want $5 a dog and people only want to pay $4 you will go broke. This is why imported vehicles are important so people can buy more affordable appliances to drive to and from work.Setting up a union is easier than setting up work conditions and pay.
  • El scotto I can get the speedometer from dad's 72 Ford truck back. I can't get dad back.
  • El scotto BAH! No dividers in the trunk for bags of onions or hooks for hanging sardines! Hard Pass.
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