• Hi Guest!
    You can help ensure that British Car Forum (BCF) continues to provide a great place to engage in the British car hobby! If you find BCF a beneficial community, please consider supporting our efforts with a subscription.
    There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Subscribers don't see this gawd-aweful banner
Tips
Tips

The V-dub is alive!!!!

Share this page

Banjo

Banjo

Yoda
Country flag
Offline
2 weeks of tinkering and messing with 1970 Bosch electric fuel injection, and I finally got the Type 3 to run today! Actually runs pretty good, even with a 100 ohm resistor in place of the cylinder head temp sensor (Now that I've proved the system, I'll order a new one)
Daunting to say the least, I resolved no less than 5 issues that each alone would have caused a no-start condition. I was "waiting on one phone call to be returned on a possible carb setup" away from giving up on the FI.
Now I can go on to fixing all the other stuff on the car. I was holding off till I heard it run.
Cracked a beer and celebrated.
 
GOOD FOR YOU!!!! I admire folks that stick to it, and actually SOLVE the problems. A triumph of man over machine...Or a viwi of man over machine....
 
Congrats!!! Just for fun (since I know nothing of these vehicles) what did you actually need to do?
 
Yeah. Gory details, please!

Glad ya sorted it, Ben! :thumbsup:
 
The history of this car is sketchy. I got it from my friend, who traded a Fiero to the kid that had it before him for it. the kid said he loved the VW, but needed a running car really quick, and he couldn't get the VW to run. It has a current registration sticker, but I think that was how my friend transferred the title to him. the inspection sticker is from 2006. I don't know if it ever ran while the kid had it, and my friend never had time to really look at it.
So I wound up with it. not running, crusty, but hopeful.
First off it had a new fuel pump, new ignition points and condenser, plugs, wires, cap, rotor. (Obviously a "throw parts at it" attempt to make it run.)
to start, the new fuel pump never worked. It was not getting the signal from the Fuel injection ECU to kick on. so I directly energized the pump with my power probe. "Clunk" removed the pump, and took it apart. cleaned out the crud and now "whirrrrr". but still no signal.
on the the ECU. figuring it was bad anyway, I cracked it open. I found a transistor that had a piece of foam rubber around the leads for insulation. it had held moisture and the leads had all rusted loose. off to the basement where I have my soldering equipment. I little time there and with the ECU back in, now I had fuel pump!
On to the engine. No spark, no injector pulse.
Spark was due to the wrong distributor cap being installed. a new "short" cap fixed that.
Injector pulse was a bit more involved. I started by ringing out the harness. I found that 2 wires that carried a "start" signal from the starter to the ECU had beeen cut off.. Fixed those. still no pulse.
pulled the distributor to check the double contacts in the base that time the injectors. Not working. a glob of rust on the lobe of the shaft had worn the tabs down till the points didn't open. some emery cloth, and tweaking of the contacts got good switching signals from the contacts. still no pulse.
checked the cylinder head temp sensor with my ohm meter. book says that at 50 deg, it should read around 300 ohms. mine read 3.8 K ohms. an open circuit as far as the ECU is concerned. so I tied a 100 ohm resistor in the circuit to fool it for now. finally a pulse!!!!!
after draining the apple cider out of the tank , and in with some fresh, I tried to fire it off and Varooom!
the best part is trying to keep a train of thought going on a job like that while only working on it 15 to 30 minutes at a time.
Phew.......
Thanks to all who offered tips for the FI system in my other post.
 
Awsome Ben! Glad to see another saved. Let me know if you have a lead on an old Bus. Then we can Dub together to the Glen.
 
You'd have to fight me for the bus! hahahahaha. Some day I WILL have a Westie pop-top.
Seriously, If you're looking for one, I'll keep an eye out for ya.
 
:bow: Impressive! :bow:
 
Congrats. Persistence paid off. I have actually done that trick with soldering the ECU previously at my garage. (Porsche thought it was a good idea to put the ECU under the driver's seat).

Good work finding the temperature sensor. A trick to adjust the warm running mixture by installing a resistor either in series or parallel to the sensor but you have to have an operating sensor to begin with.

And like they say, ECUs don't really go bad (they just corrode a little)
 
:lol:

Good post, Ben. Shows the "chain" of diagnostics well! And how a seasoned wrench approaches an unknown, non-running car.

I always preferred the CIS system to the electronic induction.
 
more playing with the VW. I got a new Cylinder head temp sensor, and that helps the cold start immensely! I've been playing with electronics, fixing things like the turn signal cancel mechanism, the melted connector on the ignition switch, and faulty horn circuit. I've also cleaned up the engine bay and re-installed the "atari" in its proper home.
Now here's an interesting feature. the rear quarter windows are the "pop-out"type that have the little latch at the back to open them up and allow some air flow. Today was the first time I tried to open one. it opened just fine, but I was shocked to see that the "hinge" at the front of the window is to flex the glass!!!!!.
There is no pivot point. it's hard mounted in the gasket for the about the first 6 inches , and over the next 24 inches or so it just flexes out to open.
It was a little worrisome, but then I figured it has worked for 40 years, and the glass is still on one piece.
 
I've notice that myself. I seem to remember it looks like the chrome frame flexes where it mounts to the front post under the rubber.

Glad the type3 is working out for you.

I had once installed one of those engines, with FI, in a 66 Baja Bug.

BUG66.jpg
 
Dual wheels?! that's awesome!
 
Back
Top