hot start problem 3bg v6 4m

[ronald1983]

hello german passat friends!


first of all, my name is ronald and i'm from holland.
i've signed up here because i'm a big fan of the vw passat.
the problem is, i can read german, but writing it is a bit of a problem.
so i hope if i write it in englisch it's ok.

so here's the problem from my vw passat 3bg V6 4Motion(benzin). 2002

when the egine is cold the is nothing wrong. but when i driven for a while and than shut off the engine,(so normal hot engine) it's onable to start the engine again the start motor is running but the engine wont turn on. wait for 15 min and it runs ok again(verry anoying!)

i've already changed my temp sensor, 6 new sparkpulgs(just in cause)
the car was put on the computer and there where no failures. so i've think it is something mechanical.

hope someone's reconises the problem so it will spare me some money to go to the garage. because they don't have allot of experence here with the v6 egine . so i thought i'll do the first investiqetion myself..

thank you!

 

[Balimann]

Do you drive with an lpg system? The systems starts to lean, check the lambda addaption.

 

[ronald1983]

no, i dont drive lpg

 

[der_Dave]

I know of a similar problem in the Golf4 1.6er engines. Here is the engine speed sensor G28 faulty. If it is warm and you start, you can detect the start speed in the tachometer(RPM)?

 

[spacie]

How hot is the machine after running 15 mins?

 

[Schlotti]

A Friend of mine had the same problem a while ago...
His car is Skoda Octavia 1.9TDI...

He only had to change his battery... Why? I dont know... After changing the car turned on without any problems.

Maybe thats also the reason at you car ?
Do you have the opportunity to test another battery ?

 

[mac]

Does it hot-start with the throttle fully open? -> pls. try!

Maybe leak-air makes the mixture too lean. When the engine is cold the injection control enritches the mixture and a litte bit more air doesn't matter, but when it's hot it doesn't enritch and leak-air plays a role.

Check by PC (coolant @ min. 85°C, engine idle, all electrical equipment off): 01 Engine -> 08 read block ->group 4 -idle-stabilisation- -> if field 3 shows something around -0,7g/s (it's the learned airmass correction for idle) the engine has leak-air

->check vacuum-system
->check sealings of the air intake behind the air-mass-sensor
->check tube betwen airbox and throttle for leaks
(there are leak-test-sprays available, whitch make the engine idle-rpm break in if the fluid gets into the intake)

regards,
Markus

 

[ronald1983]

- at the temp meter the car is beginning to go to the 90 deg.

- when the trhottle is fully open it also wont start.

- when the speed sensor is defect you can read this in vag com isn't it? the car has no failure's when it's on the computer.



Check by PC (coolant @ min. 85°C, engine idle, all electrical equipment off): 01 Engine -> 08 read block ->group 4 -idle-stabilisation- -> if field 3 shows something around -0,7g/s (it's the learned airmass correction for idle) the engine has leak-air


this is what i will check.