[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [New Search]

Re: [T3] Fuel injection relays - no second click


On 13 Apr 2003 at 9:31, Aaron Clow wrote:

> Anyway, hoping someone can help: I hear the first main
> click when I turn on the ignition and it sounds like
> something starts humming away in back of me (system
> pressuring up?) and it stays on as long as the key is
> "on."
> 
> I do not hear any second click afterward a second or
> two though. Where is the click supposed to come from
> in the car, what is the second click supposed to be
> and why wouldn't it be happening?

The lack of a second click means that something has been miswired in the fuel 
pump circuit. This is a safety issue and can also be a running issue.

The first click is the main FI power relay, under the back seat, clicking ON 
AND the fuel pump relay clicking ON at the same time. The second click is the 
fuel pump relay clicking OFF when the brain detects no motion of the engine for 
about 1 second.

If this is a very late 71 or a 72 this most likely means that there is a 
miswired connection on your starter which makes the FI think the starter is 
running all the time. This will make the FI run rich (because it thinks you're 
still trying to start the car.) This is covered in the Bentley manual. See the 
note at the bottom of page 25 of the Fuel chapter. This can also happen in 
other years, but is most common in the 13 months when VW ran TWO similar wires 
back there.

It could also be that someone just bypassed the fuel pump relay, which is 
(should be) under the dash. This would just be a safety issue since the fuel 
pump wouldn't shut off in case of an accident. The fuel pump relay is screwed 
to the "firewall" just up and left from where the steering column passes thru 
it.

Let us know what you find. It should be simple and easy to fix, and it's 
important to do so.

-- 
*******************************
Jim Adney, jadney@vwtype3.org
Madison, Wisconsin, USA
*******************************

-------------------------------------------------------------------
List info at http://www.vwtype3.org/list | mailto:gregm@vwtype3.org


[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [New Search]