A friend near Charleston, WV has a late 70s Super Beetle that is generally original and retains the fuel injection. He called regarding a problem he was having with what I would call the flow meter. I know AC Porsche, but not AC VW, so I can't offer much beyond to suggest carb'ing it or to put a 930 engine in it. He's traced the engine crank, no start to some spots in the flow meter where the wiper hits some open spots. The description sounded like the flapper-style flow meter found in early FI systems like Ford's Speed Density. To help in the search for a solution, what's the recommended fix for this apparently common problem and are there any 914 or Vanagon or ??? parts that are a reliability/performance upgrade. Anyone have some parts collecting dust that would get him on the road?
Also, he mentioned he has a Metropolitan engine and maybe gearbox that are surplus to his needs.
I very briefly had a Super convertible about 10 years ago and I remember everyone here saying that the fuel injection system is actually very good and should be kept. IIRC it's a Bosch system that is actually very robust, but most people replace it with inferior carburated setups because they don't want to learn anything about it.
I haven't been in that world for a very long time but there are tons of resources available online. Sounds to me like it might just need an AFM rebuild, and there are a number of vendors that offer the service.
About the AFM: http://www.type2.com/bartnik/afm.htm
About the system in general: http://www.vw-resource.com/fuel_injection.html
If you pop off the black cover, you can very gingerly bend the arm if it is so worn that there are dead spots in the tracks, so that it follows "fresh" traces. Think shortening or lengthening the little 'a-arm' that the two contacts ride on, such that the follow the same arc, but are slightly closer or farther from the pivot.
Or, remans are still available online for like $75. Also, depending on the model the fuel-mixture is set depending on where the tension spring sits in a toothed wheel. I'd probably start with an ohm meter and validate whether the resistance curve for the flapper has dead spots before doing anything.
In reply to Apis Mellifera : the afm on my 78 vw bus which was similar not identical was rebuilt by fuel injector corp 2246 n macaurthur dr Tracy ca 95516. It cost $200.00 but that was five years ago. Hope this helps
Tyler H said:I'd probably start with an ohm meter and validate whether the resistance curve for the flapper has dead spots before doing anything.
I believe he did exactly that and determined that there were open spots.
JThw8
UltimaDork
8/8/22 8:50 p.m.
Sounds like he's on the right path, but another thing to investigate which has netted me more free/cheap FI VWs than any other is there is a set of points in the distributor UNDER the ignition points which send trigger pulses to the injectors. They are always overlooked/forgotten/unknown. On more than one occasion I've paid my money/signed papers/etc and waited for the seller to walk away then popped the dizzy cap, dug down to the 2nd set of points, gave them a quick file and drove the thing on to my trailer.
Is it Bosch D? It's really easy to service once you familiarize yourself with it.
No second set of points on the Type 1 injection. That was only for the type 3 injection pancake engines.
you can carefully pop off the plastic cover and see the wiper arms. a visual inspection would probably help find the bad spots in the tracks. Hopefully its just a spot of corrosion.
While in there look for vacuum leaks. The rubber bits are historic now, and a slight leak will keep the flapper door from moving. Many cars of the era used this system, nissan had a similar one on Zs and I bet there are others.
