Bit of a weird one this, well I think it is, if anyone knows this straight away I shall be most impressed, but I’ve never heard of it before. This morning I was driving to a work mates to pick him up and just as I was getting to his house noticed that the rev counter was sat at 0. Pulled up on his driveway and turned off the engine and restarted it and still the rev counter sat at 0. Thought oh brilliant something to sort out, then as my mate was getting in the car it cut out. Then it wouldn’t restart, it was turning over but wouldn’t fire, after about 5 or 6 attempts it fired, the rev counter worked and I’ve just managed to get to work fine with no issues. Now I’ve noticed rev counter issues twice before, once on Sunday on the way back from Liverpool, the car had probably been running less than fifteen minutes. The other time was months ago, probably December or January and I had driven for about 2-3 minutes and the rev counter went wappy, just randomly sweeping about the dial, then it went back to normal but as it did, the car gave a little splutter. It never did it again so I forgot about it. It did the wappy thing on the Liverpool journey too, it has never done this going to 0 thing until this morning.

Now apart from this the car is running absolutely bob on, in fact on my last tank of juice I averaged 40.5mpg (that’s not granny driving either). I’ve no idea what this issue is and I hope all that has made sense, if anyone has any ideas, please let me know!

Yeah, that's an odd one. On Spi's (not sure about G40s), the rev counter gets its readings from data supplied by the hall sender. When said hall sender started to die, car would cough and splutter at the same time the rev counter needle would thrash from 0-3000 rpm or anywhere in between. However, I’m not sure this is the same issue with yours as the engine was running at the same time as the rev counter died, if I pick you up correctly.

Hmmm I did wonder where the rev counter got its signal. I think it sounds like the hall sender is on its way out then, brilliant. Yes the engine was still running when the rev counter did its funky stuff but still it does sound connected.

Daniel's pretty much correct. Hall sender signal goes to ECU, then there's a signal from the ECU to drive the coil and rev counter.

Yoof's GT used to do this sporadically. Then one day it died completely.

I couldn't remember if it was the hall sender or the coil which fed the rev counter. Deffo electrical fault.

It was the hall sender that died with Yoof's then Andy? I'll get another hall sender and swap it, I'm not paying for an exchange dizzy!

VAG G40 hall senders are about £60! Although i think you get a new trigger wheel as part of the kit though.

Well I've rung the stealers and they want £114+vat for an exchange dizzy. Pete and I have swapped one before (read repaired when he twatted it off the top of my dizzy and we had to solder the wire back together)!

I was going to see if there were any low mileage ones in the scrappy and nick it out of there, I thought the hall senders were all the same?

Imho its false economy to buy second hand electrical parts for mk3 polos and older. The cars are about 15 years old, so i would just fork out for a new hall sender or dizzy. The later dizzy hall senders are the ones to go for, off the mk4 polos if you do want to get one from a scrappers. They have the better designed pick ups on.

this is exactly what mine did a while back. it would be fine for ages then just randomly stall and not start. one exchange dizzy from vag and it was fine again.

Yeah I suppose so Nick, I'm just being a pikey! I'd better get my arse in gear, I've got a fair amount of mileage to cover in the next few weeks.

I feel for you I've got similar problems, I changed the coil as there were a few issues other than the very occasional rev counter wapping that suggested that was on its way out, was much better all round but then started typical lambda symptoms so unplugged that and he was absolutely fine so just put on a new one but the problem has come back, hes fine when cold but then he starts to get warm is really stuttery at low revs say anything under 2.5k, fine over that, doesnt even cut out just sort of a real lag when you go to pull away then shoots off! I'm wondering if not having the lambda connected has annoyed the blue temp sendor so going to try another one first before i go messing with hall sendors!

Hope you get it sorted anyway

Well I got in it last night after work and it started and drove fine and then after a couple of minutes the rev counter sat on 0. After about 5 minutes it started working again, was sat in some horrendous Sheffield city centre traffic and was hoping it wasnt going to die completely. Its obviously got bad quite quickly so will try not to use it until I get a new dizzy.

i have a mass of dizzy spares sam, and i have mastered fixing them, if you get really stuck, you can borrow the one of my gt, while you fix yours, options really...

Dan your a star. I might just take you up on that. I'll give you a shout on MSN or something later, either that or bob over at the weekend at some point.

I'm out touching up cars all weekend so feel free

can test it too on birds car