Citi Golf 1.4i Tachometer acting strange

Post Reply
s_luca_07
Enlisted
Posts: 6
Registered for: 4 years 2 months

Citi Golf 1.4i Tachometer acting strange

Post by s_luca_07 »

Hello everyone, I need your advice on an issue that is annoying me.

After not driving a lot during Christmas time, my car didn't want to start so I had to jump start it. Someone helped me and they removed the positive from my battery, and, to the best of my knowledge, they connected an extra battery in series with my flat battery, thus starting the car.

The same morning I noticed my revs were not working. Car is driving fine but it shows 0 revs, needle is right down. I didn't think much of it and eventually everything was back to normal, revs and all. Next day there wasn't an issue either.

Now the problem is back. If I start the car there is a squeak on the fan belt and the rev meter is working, then the squeaking stops and the tachometer doesn't work anymore. Actually, when I idle it shows idle, but as soon as I accelerate, it tries to go up and then goes right back down to 0.

The funny thing is that if I have the fan and the lights on, revs show up as usual. As soon as I switch the lights off its back to 0.

I asked around and there are a few theories. One is that the alternator was damaged when the batteries were connected in series and is now acting up? Another one is that the tachometer doesn't have a proper earth and when I switch other things on it gets the earth from them? Maybe it's related to the issue of the battery losing charge over the few days, which it didn't use to?

Upon diagnose we realised my coil was on its way out, so I replaced it with one bought from Midas. The new one works fine, it also has a 3 point plug but also an external wire which my previous one didn't have. I cleaned the coil's earth to the engine and it seemed to help a bit but its back to the usual. Correct reading when idling, 0 when driving unless I have fan and lights on.

It's a 2001 Chico/Citi golf 1.4 injection, square dash and pretty stock under the bonnet. Everything else in the cluster works, speedometer, fuel gauge, temperature etc. Only the tachometer is acting up. Any advice is appreciated. And also, what is the extra wire (with a plug on the end) at the coil? I don't want to try and earth it only to break more stuff.

I plan to clean all earth connections and wires I can find, the negative of the battery, starter wires etc, and see if that solves anything.

I am trying to think of anything that can help... Every now and then when starting the car in the morning the oil pressure light would stay on and I would have to switch off and on again so it would go away. I don't know if it's related to my problem. Otherwise it doesn't normally have electric problems, it just doesn't like the rain like any true Citi.

Any advice will be appreciated!
Thank you!
Callum229
Cadet
Posts: 251
Registered for: 4 years 1 month
Car Make: VW
Car Model: Jetta MK5 TDI DSG Highline
Location: Durban
Contact:

Re: Citi Golf 1.4i Tachometer acting strange

Post by Callum229 »

If they connected in series, that will be 24V not 12V that is flowing into your car.

Yes that might have fried a few things and maybe your alternator/voltage regulator and some wiring.

Do the simple things like check the earthing, check resistance of wires and continuity, replace any damaged wiring.

If something is drawing power it could be a short or something that isn't supposed to be on, is indeed staying on.

Does your battery light pop up when the tach dies? It could be the alternator being faulty and switching off and on or the regulator isn't regulating the voltage properly. If AC power is getting into the battery or a lower voltage is feeding the battery, it might be that the battery isn't charged fully and is just getting drained due to normal use although AC power will damage the battery.

What's your voltage readout at your battery when the car is running(use a multimeter)?

Sent from my Nokia 8 Sirocco using Tapatalk

2007 VW Jetta MK5 1.9 TDI DSG,

Mods: Simple EGR delete, LED interior set up, LED rear footwell lights, LED Puddle lamps, LED Doorhandle illumination, LED License plate lights, LED Boot lighting.

2007 VW Golf 5 1.9 TDI DSG, no mods.

2007 VW Transporter 2.5 TDI 4motion, no mods.
s_luca_07
Enlisted
Posts: 6
Registered for: 4 years 2 months

Re: Citi Golf 1.4i Tachometer acting strange

Post by s_luca_07 »

Thank you,

No battery light goes on at any stage. While the tach goes up and down no error lights pop up. As soon as I start the engine all the lights and warnings disappear, as they should. We checked the battery with the multimeter and it's 13V, and slightly more, about 0.5V more when running if I remember correctly. Didn't raise any flags there
Post Reply