Basically, a mate messaged me to ask him to help with his 1.6 AKL. Threw a code for the G28 speed sensor. Replaced the sensor 3 times. No luck. ECU wouldn't talk to vag-com or vag-commander. Checked all fuses, earths are good. Checked resistances on the sensor, all three are good. Couldn't see a supply voltage on the sensor at all - its' a 3 pin, so much be a hall sensor, rather than a VR. Not sure on the pinout though, so can't tell - RubJonny? Replaced entire engine loom, no luck. Replaced ECU with another one, ECU now talks to vag-com. Coded it in, still throws the same code. Put original ECU back in, worked for a few starts, then nothing again. Replaced with new one because it spoke to vag-com. Replaced timing belt, (same code prior to this), compression tests good, only thing I can see it being is the ring, but not sure how it could shift? Can't think of anything else, and this is the most electrically minded forum I know. Thoughts people?
What is your DTC? VAG or P code? Guessing - http://wiki.ross-tech.com/wiki/index.php/16705/P0321/000801 16705/P0321/000801 - Engine Speed Sensor (G28): Implausible Signal
P0321. Code still doesn't clear when the engine is running though. It starts, but if you disconnect the cam sensor it dies. Prolonged cranking must be due to the signal from the G28 being out with tolerances, so it resorts to cam sensor. There won't be two cam sensors due to being an 8v, but I know they're related, hence why I was adamant that the timing was spot on, he said it was. I'll search for the interference though, cheers!
resistances on CKP 2 & 3 730-1000 OHM 1 & 2 INFINITE 1 & 3 INFINITE tESTS ON cmp (g40) Camshaft position (CMP) sensor D shape connector, 1 is the 'flat end' of the D, 3 the 'rounded end' TECHNICAL DATA Terminals Resistance 3 & earth Zero Ensure ignition switched OFF. Disconnect CMP sensor multi-plug. Check resistance between harness multi-plug terminal and earth Fig.33.1. If resistance not as specified: Check wiring. TECHNICAL DATA Terminals Voltage 1 & earth 5 V approx. Ensure ignition switched OFF. Disconnect CMP sensor multi-plug. Switch ignition ON. Check voltage between harness multi-plug terminal and earth Fig.33.2. If voltage not as specified: Check wiring. Checking signal - Fig.34 TECHNICAL DATA Terminals LED 2 & 3 Flashing NOTE: Remove engine control relay or fuse before cranking tests, to prevent engine from starting. Ensure ignition switched OFF. Do not disconnect multi-plug. Access CMP sensor multi-plug terminals. Connect LED test lamp between multi-plug terminals. Briefly crank engine. Check that LED flashes.
I'm not familiar on this engine where the G28 picks up it's signal from, is it the ring on the rear main seal housing type ? Really need to 'scope the sensor to prove it out, and test the cam sensor as above. No other tests for G28 on Autodata. Found this for a mk3 ABF, I would 'guess' similar pin-outs. I don't have access to ELSAWin to get the proper one
after I cheka de WIN of elsa on the AKL sensor pins 2 and 3 are the ecu wires (63 and 56 respectively), 1 is the ground to the ecu sensor reference earth to pin 70 If it has the crank seal flange mounted sensor which i suspect it does then i you're in for a world of hurt replacing the flange, but check the wires for continuity back to the ecu to start with and just generally look over the loom for possible chafage. actual sensor checks will be as gvk already posted its a std hall effect type sensor
Hi, hoping you could help, I have the same issue on my A3 and done about all I can do in terms of changing parts, just wondering if you ever sorted this out? any pointers would be really helpful, I am currently not getting a reading on the crank sensor plug, apparently it should be giving a 5 volt reading but i got nothing.
the engine is an AKL, now i have the right wiring diagram(thanks for that!) it turns out all the wires are fine, everywhere gets a signal. it all started with having my crankshaft sensor changed, since then.........i have replaced... 1) Throttle Body 2) Cambelt Sensor 3) Temperature Sensor 4) CrankShaft Sensor (2nd time) 5) coil pack 6) HIT leads Even after all that, on acceleration the car is still jerky and doesnt run smoothly, keeps spluttering on tick-over. one thing i noticed whilst it was running a unplugged the CRank Sensor and the manuals (http://workshop-manuals.com/audi/a3...on_system/checking_engine_speed_sender_-g28/) i have read state the car should switch off, but mine kept going
is it definitely the crank sensor you were looking at, rather than the cam or knock sensors? on yours the crank sender is right at the bottom of the block gearbox side same as the 2.0 mk3 engines, the plug for the crank sensor is clipped just above the oil filter housing next to the knock sensor near the ignition coil by the looks of it the coil may be woprth a look, it seems to be mounted right on the engine itself so could suffer from heat damage
