raised idle and fast idle problems on G60.

[Redfox 10]

for a few days, after starting the car, it have been holding the raised idlespeed (1000) for longer than normal, and I must add, that weather have been 20-25 degrees cel.

Also, upon letting go of the gaspedal, I see that the engine sits at 1500 rpm, only sometimes lowering to 810 rpm as normal.

I would like to ask if someone have experienced this and could possible point in the right direction to a sensor, a thermostat or?

 

Cheers,

Redfox.

Edited July 24, 2014 by Redfox

[Album56 0]

Usually air getting into induction system somewhere where it shouldnt, leaking vacuum pipe is common, idle screw falls out of back of throttle body when seal perishes screw vibrates out is also common. Also worth checking the idle micro switch on the throttle body is operating correctly, a few things to check

[Redfox 10]

Thanks, I'll look into that, and report back what I find.

 

Cheers,

Redfox.

[Redfox 10]

Okay so far I have looked at all the tubing and cleaned them up and retightened. The micro switch is cleaned and throttle linkage is cleaned up. That seems to Work.No difference.

So, I am thinking this:: hte car seems to spend a longer time than usual to warm up, and outside it's been 30 deg. cel. for some time now. But if I let it stay and idle (raised as described), when it reaches apprx. 90 degree on Water temp (there oil will read something like 85-90 deg. cel), it slows idle Down to how it should be, and drives fien from there.

 

My guess is this: I think there may be a slow/worn thermostat in the cooling system that does not move or hang slightly, as this could explain the longer Warming up time, by using the Whole cooling systems capacity.

 

As I understand it, there are 3 sensors, one on the radiator, two on the flange above the oilfilter, and finally the thermostat inside the waterpump.

Which one could control that?

 

Now, the question is, could this be the thing?

And how to determine this and what thermostat it is, before I take everything apart? (would like not to).

 

Cheers,

Redfox.

Edited July 24, 2014 by Redfox

[Redfox 10]

Okay, here's an update for future members who may experience this problem.

The problem was twofold, consisting of the following:

 

1/ the blue top thermosensor on the front of the block, had way too much internal resistance. So I installed a new one from vw. Engine now idle and Works perfect. Fuel consumption is now back to normal very good milage.

 

2/ the thermostat inside the waterpump is stuck or lazy. Install a new one from vw, and the coolant temperature is back to normal 88-92 when warmed up.

 

I hope this will be of help to other members.

 

Kind regards,

Redfox.

[robrado974 1]

Nice one for posting the solution to the problem Red .

[Jim 2]

Indeed. Nice when people come back to post their findings / solutions rather than just vanishing. Thank you!