Polo Starting Problem (intermittent)

**Edmund** · 06-09-2007,06:01 PM

Hi, Help, as VW Dealership are stuck.

Recently brought a Polo 1.4 S 2003 - occassionally, hot or cold engine, the car wont start. Engine turns over but fails to fire. Strong smell of fuel when doing this. Most time car just starts. We only turn the key, we do not touch any pedals. However, if polo fails to start, we ram the accelorator pedal down and it starts to fire, witha cloud of smoke when it does.

Polo had full service, cleaned Throttle out and had new Cam Shaft Sensor fitted. Problem still occurs occassionally (2-3 starts out of 10 problem will present itself). Help - as VW now do not know what is wrong with it. Both AA and VW plugged into the computer and everytime computer says ... No Fault found.

Thanks

**beatoven** · 12-09-2007,07:02 PM

Hey there mate,
I have a 2000 Polo Tdi and I have the same problem. Every morning the car takes from 15 seconds upwards to start after turning the key. Sometimes it doesn't and I have to press the accelerator pedal. A lot of smoke comes out when it finally starts. Is your car VAG doesn't give any error codes for me either. Lemme know if you find something. Thanks a bunch.

**kunaalv** · 12-09-2007,08:54 PM

Hi,
Beatoven - sounds like you need to replace your Glow Plugs if its taking you that long to start in the summer. Mine takes around 4sec for the yellow coil light to go off. Takes about 8secs in the winter months.

Glow plugs are fairly inexpensive (around £6 each), but i think the car has around 4 glow plugs, so unless you can test them, replace them all.

**a8 tech** · 12-09-2007,09:10 PM

Originally Posted by Edmund

Hi, Help, as VW Dealership are stuck.

Recently brought a Polo 1.4 S 2003 - occassionally, hot or cold engine, the car wont start. Engine turns over but fails to fire. Strong smell of fuel when doing this. Most time car just starts. We only turn the key, we do not touch any pedals. However, if polo fails to start, we ram the accelorator pedal down and it starts to fire, witha cloud of smoke when it does.

Polo had full service, cleaned Throttle out and had new Cam Shaft Sensor fitted. Problem still occurs occassionally (2-3 starts out of 10 problem will present itself). Help - as VW now do not know what is wrong with it. Both AA and VW plugged into the computer and everytime computer says ... No Fault found.

Thanks

The crank shaft sensor causes this and the ecu see no signal so defaults to the hall sender (cam shaft sender) to start, as fuel is there but no spark.I would start there even though there is no code as the engine runs so the ecu thinks all is ok or the coolant sender is reading -50 at cold start.

**beatoven** · 13-09-2007,08:47 AM

Thanks kunaalv. I was about to change the glow plugs but when the mechanic checked them he said they were all working fine. The coil light always glows for only half a sec, be it winter or summer, hot or cold. I really don't know why it doesn't stay 'on'. Could it be a sensor for the temperature causing this?

a8tech, I didn't quite understand what you said. Is the crank shaft sensor the real cause or the cam shaft sensor? What do I need to replace first?

Thanks both of you for your help. No stupid mechanics in Mauritius have been able to fix this.

**Edmund** · 19-09-2007,10:07 PM

Originally Posted by beatoven

Hey there mate,
I have a 2000 Polo Tdi and I have the same problem. Every morning the car takes from 15 seconds upwards to start after turning the key. Sometimes it doesn't and I have to press the accelerator pedal. A lot of smoke comes out when it finally starts. Is your car VAG doesn't give any error codes for me either. Lemme know if you find something. Thanks a bunch.

Hi Beatoven - similar problem. So VW Dealership failed to get it started, with computer saying no fault found. However, an independent technician told me straight away, problem was not cam shaft sender (if this was faulty, car would never start), but in fact a Temperature Sender. There was no fault, but the sender is locked on -31. Changed this - £22.91 and car now works. The plume of smoke was simply unburnt fuel from me ramming the accelorator down. Reason it was intermittent was at a certain temp as it cooled, I gues this was when it failed to start. Good luck.

**a8 tech** · 19-09-2007,10:13 PM

i did say the cooolant reading wouldnt store a fault and in genral it reads -50

**beatoven** · 20-09-2007,08:49 AM

Thanks a lot for your help all of you. I've been living with this problem for a year now. I always told the mechanics that the car would start quicker when it had been in the sun for some time, and hence must be a temperature issue. They told me to change the piston ring and head cylinder gasket n stuff and said it was my engine that wasn't revving quickly enough or whatever. Fortunately, I didn't listen to them since those parts cost a lot.
Thanks again. Now, all I need is to find someone who'll let me use his VAG for a few minutes.

Cheers,

Byeee.

**beatoven** · 08-10-2007,08:53 PM

Uh... Edmund, is the temperature sender the same thing as an ECT (The green sensor that fits in the coolant pipe? Coz I changed that, and I still have the problem...