refusing to start in cold mornings

[sharki786]

Lazy Starter?

Seems like you was right. As i went to start the car yesterday and same again refused to start so finally after the 3rd crank it fired but but the starter was making a right racket so i will be going into the garage tomz and get it changed over.

[sharki786]

Issue still here. New starter fitted and still doing the same. Changed battery from the mk4, kept the car running while i removed the battery, it didnt cut out so i know the alternator is banging the right voltage out. Where is the temp sensor located? Is it on top of the coolant hose in the middle of the engine?

[boneybradley]

. Where is the temp sensor located? Is it on top of the coolant hose in the middle of the engine?

yep and it just push fits (and pulls out to remove), just make sure you get the correct colour (there's a ring around the base) and a new sealing ring

[sharki786]

. Where is the temp sensor located? Is it on top of the coolant hose in the middle of the engine?

yep and it just push fits (and pulls out to remove), just make sure you get the correct colour (there's a ring around the base) and a new sealing ring

Doea this send a temp reading to the ecu or the clocks? If non of them then whats it used for? Going to get one from mad4vw's

[boneybradley]

temp sensor does both jobs...... ecu and gauge!

[GOLF-MK3-GTI]

It's called ECU temp sensor, so I would have thought it goes to the ecu. Unplug it and try to start, see if it makes a difference. Give your starter direct power, see if it cranks first time.

I'm starting to think it could be an earth issue.

[sharki786]

temp sensor does both jobs...... ecu and gauge!

So you think its sending wrong readings to ecu?
Another thing i forgot to mention is that today morning i noticed my brake lights were on but no1 touching the brake pedal they wernt on full power just dimmed. I replaced all my rear lights with led (normal bulbs in the indicators) anyway i removed 1 brake light led and they went off replaced with normal bulbs and its all good. But car still struggles to start. Will be going to get the temp sender today.

[sharki786]

It's called ECU temp sensor, so I would have thought it goes to the ecu. Unplug it and try to start, see if it makes a difference. Give your starter direct power, see if it cranks first time.

I'm starting to think it could be an earth issue.

Unplugged the ecu temp sender still the same
Sometimes it sounds like theres enought power to crank the engine and next min its like the battry on its last legs or when i 1start it the battry sounds like its nearly dead then if i try again all of a sudden the battry has full power. This battery was running fine in my mk4 till the car was stood then it died so yesterday i swapped battry while the car was started so it should have charged the battery

[sharki786]

So little update. Replaced the new starter, still same, bought brand new battery (yuasa 550cca) still same. Last night the car refused to start i had to get a jump start and car started. Checked for faults on vagcom no faults. Checked crank sensor and wires are bare, used some tape and taped them up, still same. So i checked relays and relay 30 is very hot after the car has been running. Mad4vws will bring some over later and i will check to see if it is that.

[sharki786]

Little update. Got relay 30 from mad4vws and tried it still same. Both relays get hot after 10mins of car started. Will look at a new crank sensor