QuestionQUESTION: I've just brought home a fuel injected 1600 bug with some issues and was hoping you could help. 1st, Bug ran fine but took awhile to start when cold, seemed to have to pump the peddel to start. 2nd the fuel pump stays on all the time (even when ignition is off) and I have to disconnect the power from the battery. 3rd, now after sitting for a while it's not getting power to the starter, seems like some clicking noise is coming from behind the glove box when key is turned on to start pos., is this a relay or something? Also has some kind of seat belt safety switch under the seat. This looks like its all there and with the seat belts connected still isn't getting any power to starter when key is turned. I ran a jumper wire from starter to battery and it rolled over. Any help with these issues would be greatly appreciated. thanks
ANSWER: Hi Jason,
First of all, congrats on getting such a cool ride!
Now for the problems:
- The hard starting when cold is likely the cold start valve (5th injector) or the Thermo-time switch which controls it. The Auxiliary Air Regulator also plays a part in keeping the engine idle higher during the warmup period.
- The fuel pump is controlled by the double relay. The double relay is enabled 2 ways:
1) When the key is in the START position.
2) Once the engine is running, by a micro switch within the air box.
Obviously, something is wired very wrong; the fuel pump should NOT be on when the key is OFF, in fact not even with the key ON if the engine is NOT running(this is a safety feature.)
- Aircooled VWs are prone to starter problems due to:
1) Low voltage from the ignition switch. Some folks use a "intermediate relay" to boost the signal.
2) The ignition contact at the solenoid could be loose or dirty because of the environment it's in.
- The seat belt warning circuit only has an effect on the starter for 1974 models.
If you need any more details on any of these subjects, just shoot me a follow up, I'd be glad to get into more specifics.
- Rick
---------- FOLLOW-UP ----------
QUESTION: Thanks for the info. Could you tell me where the thermo-time switch is located, also how to test this and/or the 5th injector. Can the dbl relay be tested, and where is it? I also have a 1970 sunroof bettle and the back of the sunroof is not sealing right when rolled all the way shut. Looks like the front is good, and if I push up on the back of it from inside the car it moves up and then seals nice. Is there a way to ajust this with out removing the head liner? Also theres a little red button in between the head light and wiper knobs. Looks like it has a B on it, its about 1/4 inch around and sits in a round recessed black circle about the size of the other dash knobs and looks to be a factory option. thanks again for any help
Answer
FI_engine
Jason,
See the diagram:
1 = Cold start valve (5th injector)
2 = Thermo Time switch
3 = Double Relay, location behind the back seat, passenger side, approximately on the other side of the firewall where the arrow is pointing; close to the computer.
To test the cold start valve:
- Disconnect the coil to distributor high tension wire so the engine will not start.
- Remove the cold start valve from the engine; leave the connector on.
- Get a small container to catch the gas which should be expelled from the valve in the next step.
- Have someone crank the engine while you observe the valve shoot gas. This should only happen for a few seconds because the Thermo Time switch should timeout. If it does, the circuit is good.
- If there is no squirt, or it just happens too quickly and you need to test longer, disconnect the electrical connector from the Thermo Time switch and short the contacts of the connector together (not the switch contacts). This will bypass the switch and allow the cold start valve to shoot continuously while cranking. This should narrow down the problem further.
As far as the sunroof, you need to do the rear edge adjustment and this should fix it. You do not have to remove the headliner, but the sliding "trim panel" must be disengaged and moved fully to the rear to get to the adjustment mechanisms.
The little red button the the "dual brake warning system". There are two sensors on the dual brake master cylinder, one for each section, front and rear. If either section goes bad (loses fluid or pressure because of bad seals), you should get the light, but only when pressing the brake, and only if ONE of the systems is bad at a time. You can press the button anytime as a lamp test only; but it does not validate the brakes are good by pressing it with your finger.
- Rick
