Mk1 Cabriolet - does not want to start!

[Vilz]

Hi all,

I am having trouble starting my 1991 Cabriolet. When I turn the key the car tries to turnover but it can never quite do it.

All this started when previously when driving the car, it would just turn off. After turning off during driving, it would not restart for about 5 mins and then it would be fine. This started happening more often, to the point where it just doesnt start anymore. Battery is ok and fuel pump seems ok too. I have heard that it could a relay, but I don't have a Bentley so I do not which relay is the fuel pump one.

I have tried to sell the car as I have bought a MK2 GTI and would like to invest some money into this now, but a car that is not running seems to be hard to get rid of. I have decide now to try and fix it and get it running again as its a nice car.

The car has been sitting in the garage at my dad's for a while now as I haven't had time to try and fix it.

Has anyone else had similar issues and does anyone have an idea what it could be?

Thanks in advance.

Vildan

[paulie71]

Depends on whther you have Digifant or CIS fuel system. If it's CIS like my 93 cabby, the relay is (from the bottom of the fuse box) 2nd row and second from the left. They are about $40-$50 to replace. Fuse should be 5th from left (15 amp).

If in doubt check out Cabby Info - Home

they are a wealth of info

[Vilz]

I am pretty sure its a CIS (K-Jet). I believe all aussie delivered cabs were CISs.

Thanks for that website, there is some great info on it.

Is there a way of checking that the relay/fuel pump is working?

[Jarred]

you should be able to bridge the relay.

Ie take it out, and connect a piece of wire into where the relay normally sits. Can't remember which two spots it is, but it should provide constant power to the FP.

So bridge it, let it run for 2 seconds, and try and start it. IF it doesn't start, take it out again, otherwise you'll flood it

[paulie71]

Here's one idea from VWVortex forum
VWVortex.com - Everyone with CIS needs one of these.

Bentley Bible says to bridge terminal 30 (battery power) to terminal 87 (switched relay output). Maybe a strand of wire with a male crimp terminal at each end with a simple on-off switch might do the trick.

[Vilz]

I found that thread as well. I haven't had time to try anything yet, I am gonna try a few different things tommorow and see if I can diagnose the problem.

I am not sure what else it could be really...