I have had the car scanned on vcds for fault codes but don't have access to it myself.Welcome to ownership of the best version of the A2.
VCDS is, or should be, mandatory for FSI owners.
It impractical to troubleshoot an FSI without it.
Mac.
Did the scan show any engine faults?I have had the car scanned on vcds for fault codes but don't have access to it myself.
That's the scan taken after.Good Evening Richie,
Can we assume that VCDS scan above was before you replaced the G83 and inlet manifold?
Is VCDS now (after) showing no faults?
Andy
Hi Andy,Good Evening Richie Again,
Okay, I read this as the repair work did not fix anything.
Coolant Sensor.
Either the wiring or (both) sensor at fault and may well be the cause of you warm start problems. Was the replacement sensor genuine Audi?, if not replace with genuine Audi but before you do inspect wiring.
N316
I wonder if flap adaptation has been performed?, amounts to running basic setting I think. I also wonder if the manifold replacement was undertook with the flaps pinned up as per workshop manual? There are a few things you can check, peruse this thread....
fault p1031
hi guys, im new to this site and also a relitivley new a2 owner (12months), i love my little car however i have had a few niggles with it and having paid out at main dealers thought i would seek alternative advice, my latest prob is the engine management light being on, its saying fault p1031...www.a2oc.net
Andy
And, again as Andy says, you also need to get the G83 Coolant Sensor working, I suspect wiring/connectors. The G83 sensor plays a key part in controlling the thermostat and the cooling fan. Without the sensor output getting to the ECU, engine temperature control is compromised, and falls back to a safe default, to protect the engine, but will detrimentally affect performance, and mpg.The adaptation is done with VCDS. Must be registered Lite, or full version.
It is essential, as Andy says, after the work you've done.
Mac
Poor starting from warm may be down to the electric fuel pump, in the tank. It normally runs at 3.8 bar, limited by a bypass solenoid, which bleeds pressure off via the return line. When the engine is warm, the bypass solenoid is closed, boosting the electric pump pressure to 5.8 bar. This increased pressure is needed to prevent fuel at the input to the engine mounted High Pressure Fuel Pump, (HPFP), from vaporising, due to the pump being at engine temperature. If the electric pump pressure is low, (<3.8 bar, ignition on, engine off), then vaporising can occur when running too.The only practical way to check this, and many other FSI functions is with VCDS.I have previously replaced the g83 sensor. Also found that the flap actuator arm was broken so replaced the whole inlet manifold for a good one. Not sure what to do next. Anything else I do would be a wild stab in the dark.
The car runs fine from cold then intermittently sluggish/ hesitant when warm. Also has a problem starting from warm.
Hi Mac, thanks for the info.And, again as Andy says, you also need to get the G83 Coolant Sensor working, I suspect wiring/connectors. The G83 sensor plays a key part in controlling the thermostat and the cooling fan. Without the sensor output getting to the ECU, engine temperature control is compromised, and falls back to a safe default, to protect the engine, but will detrimentally affect performance, and mpg.
If you have a multimeter, unplug the sensor, and compare it's resistance to the sensor it replaced. If they are similar, that would point to wiring/connectors.
Good luck
Mac.
Poor starting from warm may be down to the electric fuel pump, in the tank. It normally runs at 3.8 bar, limited by a bypass solenoid, which bleeds pressure off via the return line. When the engine is warm, the bypass solenoid is closed, boosting the electric pump pressure to 5.8 bar. This increased pressure is needed to prevent fuel at the input to the engine mounted High Pressure Fuel Pump, (HPFP), from vaporising, due to the pump being at engine temperature. If the electric pump pressure is low, (<3.8 bar, ignition on, engine off), then vaporising can occur when running too.The only practical way to check this, and many other FSI functions is with VCDS.
A registered copy of VCDS Lite, (to run on any Windows laptop, XP - 11), which will do everything you need, (but only on pre 2005/06 VAG vehicles), costs $99 for registration, plus less than £10 for a lead.
So for the cost of an hour or so's labour, at a garage, you're able to troubleshoot yourself.
Mac.
Good Evening Richie,Hi Mac, thanks for the info.
The default mode for the G83 makes sense as the cooling fan has recently started to come on from cold. I originally changed that sensor as the temp gauge wasn't working. If I remember, that didn't solve it and I damaged the thermostat housing trying to replace the thermostat, which turned out to be rusted solid, and ended up replacing the whole thermostat housing end the temp gauge has worked fine since then.
Plenty to think about. Thank you.
I can understand Andy’s comments.Good Evening Richie,
Probably just me reading too much into your post but I thought there was a hint you were discussing the G62 engine outlet temperature sensor.
More to add over the weekend.
Andy
You and Andy are both right..I can understand Andy’s comments.
The temperature gauge, although driven by the cluster, not the ECU, uses the temperature from the Engine Outlet Sensor, G62, not the G83, Radiator Outlet. .
Mac.
We've all been there ...You and Andy are both right..
Some conflicting Google results confused me when looking up the part number.
I have in fact not changed the G83, grey, sensor.
Thanks for pointing that out guys, was on course for going round in a big circle.