High idle and poor fuel economy

reverend-frog · 09-05-17, 04:30 PM

My B4 Coupe (2.0 16v) has a high idle and returns about 20mpg with mixed driving.

My mechanic hooked it up to his VAG 1551 machine and it fed out the following:

"00516 030
Idling switch-F60
Open/short circuit to positive"

Thoughts? Do I need to find myself a throttle body or is there a simpler solution?

mikes2 · 09-05-17, 05:26 PM

switch should be available separately. It could also be a wiring fault

reverend-frog · 09-05-17, 05:28 PM

Quote:

Originally Posted by mikes2

switch should be available separately. It could also be a wiring fault

would you have a part number for the switch? cheers for the reply

mikes2 · 09-05-17, 05:42 PM

looks to be 048 133 154

msh · 09-05-17, 07:16 PM

I'm afraid this will be the situation where proper diagnosis will be needed, because "change everything until it works" will gonna be expensive. I said "proper", because I have no belief in self diagnostic abilities of these simple ECUs [because of experience that it's usually useless] and idle switch problem won't really affect fuel economy, just idle.

As for the particular fault code, inspect throttle and measure switches with multimeter - "open" means it's never engaged at all, that could happen if throttle is misadjusted or something is wrong with throttle cable or pedal, just open and close the throttle with hand when it's quiet around and hear if idle switch clicks, if it doesn't, throttle should be adjusted, if it does, check the wiring and measure if the switch really doesn't work. Five pound multimeter will be cheaper than changed something working.

09-05-17, 05:26 PM	#2
mikes2 4 ring whore! Classic Audi Club Member Join Date: Nov 2007 Location: Polmont Posts: 2,617	switch should be available separately. It could also be a wiring fault __________________ 1991 90 quattro 20v sport 1991 90 quattro

09-05-17, 05:42 PM	#4
mikes2 4 ring whore! Classic Audi Club Member Join Date: Nov 2007 Location: Polmont Posts: 2,617	looks to be 048 133 154 __________________ 1991 90 quattro 20v sport 1991 90 quattro

09-05-17, 07:16 PM	#5
msh 4 ring whore! Join Date: Jun 2008 Location: Rucava, Latvija Posts: 3,816	I'm afraid this will be the situation where proper diagnosis will be needed, because "change everything until it works" will gonna be expensive. I said "proper", because I have no belief in self diagnostic abilities of these simple ECUs [because of experience that it's usually useless] and idle switch problem won't really affect fuel economy, just idle. As for the particular fault code, inspect throttle and measure switches with multimeter - "open" means it's never engaged at all, that could happen if throttle is misadjusted or something is wrong with throttle cable or pedal, just open and close the throttle with hand when it's quiet around and hear if idle switch clicks, if it doesn't, throttle should be adjusted, if it does, check the wiring and measure if the switch really doesn't work. Five pound multimeter will be cheaper than changed something working.