Vw Golf 1.6 16v Se 2001 Starting Problems

[djm004]

I have a 2001 'Y' reg Golf 1.6 16v SE, runs great except when i try to start the engine when its just been running. in the morning starting is fine, once the engine warms up if i turn it off for a few minutes and try and re-start it just keeps turning over but not starting, after 5-15 seconds of key turning it coughs into life, bit of smoke out the back and then ticks over at 1200rpm as opposed to 6-700rpm. also when it has done this dodgy start when i accelerate there is a crackling noise coming from the engine / under the front of the car? i have had it into VW 4-5 time and each time they do a diagnostic on it nothing shows up as wrong. there obviously is something wrong with it but they dont seem to be ***** to find out? a taxi driver said it might be the starter solenoid wire that could have minute cracks in it so when hot it has expanded and makes starting harder? i just dont know what to do, the professionals cant help so im stuck? annoying because other than that it runs great, got 48.5mpg on a 180 mile trip the other day!

[Y15HAL]

Have you tried replacing the coolant temp sender?

[djm004]

no i haven't tried replacing anything as the VW mechanics have not suggested anything as nothing showed up on the multiple diagnostics other than a slightly low battery, which has since been fully charged and is fine. would the coolant temp sender show on a diagnostic? and would it be expensive to replace? also how would this effect starting when hot? not too many questions there...

[Y15HAL]

im not too sure if it would come up on the diagnostic.........

they are only around £20-25 from the dealers....

This effects starting when hot, because i think when the car is warm, the faulty temp sender doesnt know the temperature of the car, and doesnt know how much fuel to provide....not 100% if thats the reason, but i used to have issues with warm starts, and that fixed it.

Not too much money, so could be worth a shot?

[djm004]

cheers for that, i will give it a go. anything is worth a try to be honest, will keep you posted.

[Y15HAL]

Good luck mate

[djm004]

just had the car down to VW and it turned out the coolant temp sender was faulty so it made the car think it was cold all the time. seems to be perfect now, 2 hot starts no problem. really appreciate the help, thank you.

[kevsambells]

i also have this prob 2 every nw and then ive been told by a vw specialist that it could be the alternator is not giving the starter motor enough kick 2 start it due to a lot of short trips. im going to change the starter as well as the alternator to over come this problem hope this helps

[djm004]

My car is working perfectly still so it was the coolant temperature sensor. no one mentioned the alternator to me, might want to get them to test the coolant sensor first before you incur all the costs? sorry for the slow reply