S4 EGT Sensor

A

aragorn

"Stick a V8 in it!"
Staff member
Moderator
VCDS Map User
Joined
Jan 30, 2008
Messages
18,708
Reaction score
909
Points
113
Location
Glenrothes, Fife, Scotland
So i've got this fault code:

17866 - Exhaust Gas Temp Sensor 2 (G236): Short to Ground

Any idea which bank this is on?

I know one is "easy" to change, and the other one is a pig... Looking at the engine, the "offside" bank looks to be quite easy to access, whereas on the nearside i cant even see the sensor!

Cheers.
 
Bank one is the left side
Bank two is the right side

Bank one is the pain, it is located on the underside of the turbo/downpipe, you can get at it from the under the car. There is a small gap between the drive shaft and the subframe to get you hand in with an adapted ring spanner to remove it. Needless to say wait for the engine to cool !!

Hope this helps.....
 
Ahha! So the faulty one is the easy one then! Thats one bonus anyway.

I've reset the code. Will see if it comes back or not and then look at ordering a replacement if it does.

Are these sensors known to fail by themselves, or is it some other faulty component that causes them to fail?
 
The EGT`s can be helped on their way by faulty mafs.

They can also be damaged by the exhaust manifold failing. The double skin manifolds can fracture/welds fail and the loose part can damage the EGT.
 
I presume if its damage from the manifold i will see it when i remove it?

Not sure if the MAF is faulty or not. The enignes never quite been 100%. Theres no boost leaks, however on a full throttle 3rd gear pull it was cutting throttle drive back to 50% (only noticeable on vagcom, the car drives normally) and the peak g/s was indicating about 255-260hp, ie a bit short of normal. Cant really find any explanation for this low figure though...

Cheers
 
Had a little test drive earlier to see if we could get it to pop the EGT code again.

Didnt seem to but i managed to get a log of the odd throttle cut:
main.php


Thats only 2nd and some of third, theres not really enough road round here to do any more quickly.

As you can see, throttle starts off at 100%, then drops back, reaching ~75-80ish in this case.

For some reason this S4 ECU doesnt register spec'd boost against actual on channel 115, but looking at the actual value on channel 118, it seems it spikes to around 0.65bar when the throttle was first put down, then drops back and holds around 0.5-0.55bar, which doesnt seem particulary excessive?
 
You might want to check the fueling. I know you get overfueling with a bad EGT,
perhaps you get throttle cut as well?
 
Ye, this EGT fault is relatively new though, its had the throttle cut since he baught the car last year.

It doesnt fault code (well does now obviously but didnt before) and drives completely normally, the cuts only visible when viewing the logs on vagcom, and you cant even feel it.
 
Look as pending codes as well......

Fault codes are only stored if the error lasts for, I think around 30 secs.
 
You must log in or register to reply here.

Similar threads

AndyC
EGT sensor
Replies
4
Views
1K
AndyC
AndyC
S
egt sensor
Replies
2
Views
861
Siena
S
S
S4 B5 EGT sensor readings.
Replies
0
Views
1K
smoking_bob
S
JoeeS3
Egt sensor fix!
Replies
2
Views
932
JoeeS3
JoeeS3
stapo69
S4 EGT fault
Replies
4
Views
1K
stapo69
stapo69
Top
Back