1970 VW Fastback - running great for the past several months but

Hi,

I’ve had my 1970 VW fastback (automatic stick-shift with fuel injection) for about 6 months. It’s my city driver to and from my work (about 10 minutes) in Portland. It has a cracked engine case so I monitor the oil (and plan to replace the engine one of these days) but otherwise had run really well. It recently stopped running in the middle of the street. I was going up a hill and was putting a little gas in and the engine just shut down. The lights still worked, the radio as well, the oil was fine, and there was 1/2 tank of gas. However the engine wasn’t turning over. I changed out the batteries (we keep a spare charged battery since the car can’t be jump started) in case that was the problem. It started right away. The battery I removed had about a 50% charge - it’s a new battery and neither the lights nor radio was left on when I parked.

  1. Is it possible the fastback stopped running because the battery got low?
  2. If so, is it possible I wasn’t driving it far enough (never more than 10 minutes in the city) or is is more likely an alternator issue?
  3. Any reference info you’d recommend for the VW T3?

I have a couple books (How to Keep Your VW Running and a repair manual for the VW T3) that I’m looking through but haven’t found the answer.
Thank you so much!

  1. yes
  2. yes

Would this serve your purposes?

http://www.bentleypublishers.com/volkswagen/repair-information/vw-type-3-1968-1973-repair-manual.html

I think the battery power got to low to run the fuel injection system, perhaps the fuel pump stopped running or it was running too slow to provide the needed pressure and flow.

It is pretty easy to have the alternator output checked. If the alternator checks OK then perhaps you need to put a battery tender charger on the car when not in use. If you are not near a 120V outlet there are solar battery chargers available.

Thanks you so much! It’s my first older car and I love it!

I live in an apartment and actually rent a garage spot (no outlet) so we have a 2nd battery that we keep charged in the apt, but maybe I’ll move the charged battery to the car (and check it once it awhile) in case this happens again!

Thank you again!

Go to thesamba.com
There are several experts on VW fi systems and later aircooled cars but one in particular is encyclopedic. Ask a guy that goes by the handle ‘tram’.

Thanks for the info!

So, How often do you use the spare battery?

Perhaps you can steal some juice from all those EV charging stations. A 440V charger would give your battery a flash charge, I was going to suggest a solar trickle charger, but PDX doesn’t get much sun for 8 months.

With an old car like that and short drives it might be worth using a ‘battery tender’ if you have access to a plug. They sell them on Amazon.

Yeah you probably just ran the battery down from short trips, but its relatively easy to have the generator output checked.

Now really though, I got T boned in my VW in town and it was not fun. The thing folded up like an accordian. Yours is ten years newer but the same aged technology. If I were you I’d get a little newer daily driver and just use this one for shows.

I’ve had my 1970 VW fastback (automatic stick-shift with fuel injection)
I didn’t know that the VW Fastback was availble with automatic stick-shift. The VW Beetle of that time period had the automatic stick-shift as an option. I thought that the Fastback and Squareback were either the manual transmission or a regular automatic transmission.

A new battery doesn’t necessarily mean a good battery. Assuming that battery was charged and tested good, have you checked the alternator belt and verified that the alternator itself is producing what it should?
A VW air-cooled does not tolerate worn, glazed, and slipping belts at all.

As to abruptly dying on the road there are a number of common faults that can cause this other than battery voltage dropping too low.
The more common causes might be the ignition switch, fuel pump, or the double relay.

Unless your car was revamped, the fuel injection is probably mechanical. So a low battery wouldn’t likely put that out of commission, but if the battery got too low, the ignition system would stop operating. But you said the lights, radio, etc. worked, so I question whether the battery was the culprit. A battery has to get pretty low to cause an old car to stall out, unlike a modern, computer-controlled vehicle.

If you have to frequently jump start it (or use a spare battery), why not get one of those rechargeable jump starters that you can keep in the car?

Actually I think those VWs had electronic FI.

Per wiki:
"The Type 3 engine received a larger displacement (1.6 L) for 1966 (August '65) and in 1968 became the world’s first volume production car to feature electronic fuel injection — pioneered by Bosch. The Bosch D-Jetronic system was offered on the Volkswagen 1600 TE & LE version "

I stand corrected. EFI was a pretty mean feat for 1968. I’m assuming it had some sort of analog computer controlling it?

I had the same car. Was driving back to college and had a case of pop on rear floor and the heat vent actually over pressurized a can of pop and it burst!!! Heat from a VW air cooled motor! Awesome.

If the battery is chronically kept under charged it will get sulfated.
Check the battery voltage with the engine idling and accessories off. Should be 13.5-14.5V.
With so many short trips I would swap batteries or fully charge the batt in the car every month or two.

Lindsay; you have my greatest admiration for keeping such a car runing. Several of my wife’s friends owned these vehicles and they all had problems with them, especally the ignition and fuel injection system which was located too close to the ground and got contaminated easily.

Visiting Germany in those days, I noticed that Germans had a very low opinon of these cars; it was called the 411 model, and the joke was that it had 4 doors and came out 11 years too late.

Doc, the 411 was a later model (‘Type 4’) than the fastback/squareback (‘Type 3’).