Instruments fuse keeps blowing

[marc69]

The fuse (no18) in my 1992 Nova keeps blowing and giving me no instruments.

The car is for the track so therefore a rev counter/temperature gaugeand oil light are a must.

It will last for a few minutes then pop....after this the red ignition light wavers about, the rev counter moves randonmly now and again.

I have driven it a bit like this and it is still charging the battery so therefore it must be a short. I noticed as the engine moves (clutch in and out) etc the red light flickering varies.

Any advice please as I'm stuck.

[brainsnova]

Bad earth possibly

[marc69]

The one from the gearbox to the body? The ignition etc all run fine now, and starting is good.

[hotrod]

Not sure a bad earth would cause the fuse to pop.

Does the fuse pop when your not driving?

If it doesnt try changing the fuse switch one thing on at a time if that doesnt blow it just try moving the harness by hand if it pops thats the area you should be checking around. simples!

[marc69]

It only pops when driving, I can leave the car idling for ages and it's fine.

For checking by switching each thing on one ata times, I don't think fuse 18 does anything else but the instruments, or does it?

I see what you mean by moving the wirs harness, to find the area.

[hotrod]

Its all we do at work when we suspect a short!

Happy hunting!!

[marc69]

Thanks for that, I'll post how I get on in the next few days.

[hotrod]

God luck!

[kevster]

i have had simaler befor it was some think touchin the back of the rev counter in the dash had to brige it .

ps sorry for the spelling

[kevster]

or the wires could of rubbed againct the shell , some were . sorry if im not helping

[marc69]

I spent a lot of time last night hunting for any bit that made it the fuse go pop. Didn't find anything electrical at all. Then I thought more about the clutch and engine movement so started shaking the engine etc and using the clutch, still no pop.

Then I decided to pretend to drive it with just the ignition on. Reverse and out of reverse, pop. Didi it again and pop (also no reverse light). I then removed the plug from the gearbox for reverse, new fuse and tried again, no pop. Sprayed WD40 on it all, put it together and no pop.

I left the car for 30 mins with the ignition on, fuse didn't blow, drove it for about 30 minutes today and still working.

I am pleased but is it seriously likely that it was this electrical plug form the gearbox that was shorting fuse 18?

Incidently, everything about this car is proving a struggle, even the insurance company now after a month are playing silly beggars, more on that on a later thread........

[hotrod]

Hey mate if its working now dont knock it!

Looks like you sussed it!;)

[andyredtop83]

On my 1.3 sr i used to own the instrument light fuse kept blowing so i called in an auto electrician and all it was is the under bonnet light that posher novas have had come loose, when i turned on the headlights that also lights up but the live was touching the bonnet and kept blowing the fuse straight away.

[marc69]

I had a short in my other nova the other week too, the alarm kept going off

Investigated it and decided the interior light must be touching the metal surrunding it, put tape round to sort it. A few days later it starts to go again.

I put a 30 amp fuse in for a moment, heard the short ..and smelt it.

I put a wire in years ago for a boot interior light, it ran under the plastic doorstep. When I put the car back on the road a few weeks ago, I took these off and put oil in the holes to go inside the sills. I must have caught the cable on one of the screws when i put the trim back on....clever eh?