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Discussion Starter #1
Hi folks

My van is a 2004 1.9 T5 85, and it's just passed 190K miles.

Recently, it's not been starting when hot, and even more recently, it's been stalling at certain moments when hot.

It happened quite infrequently at the beginning. Once every week or so. I'd stop at a shop and it wouldn't start again until cool. But recently it's become much more prevalent and has even happened whilst at traffic lights. Very embarrassing.

The only fault that's shown was the Engine Management light flashed on one of the attempted restarts early on, but has not appeared since. I was having an issue with the van entering 'limp mode' when revved under load to over 3.5 thousand, but I replaced the MAF and things seemed to be working fine since. I'll also note, there were no engine lights showing during the limp mode period.

I have a friend with a VCDS that I'm going to borrow to try and see what codes are being shown, but I thought I'd ask here if any of you know what it could be. The van starts and runs fine when cold, although at least I think it does. Perhaps there could be a timing issue or something else dark and internal going on.

Thanks!
 

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It could be a sensor that is failing when hot. My guess is crank sensor or wiring to it but it's only a guess. VCDS will probably provide some clues.
 

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Discussion Starter #3
I had a friend say he had a similar issue with a car that ended up being the crank sensor. I'll get the VCDS hooked up and see what codes it shows. Will report back with the findings.

Thanks!
 

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As said above, that's pointing at a mission critical sensor breaking down when hot. Depending on which one it is, and what it's doing, there may not be fault codes, so looking at the various data in the measuring blocks will point the way, particularly crank and cam sensors, and all the temperatures.
 

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Discussion Starter #5
Ok, so when trying to restart the van, the RPM needle would not move, indicating a crank sensor. The VCDS showed an error code 16705 Engine Speed Sensor (G28) P0321 - Implausible Signal - Intermittent.

I've ordered a new crank sensor and will update on whether or not that fixes things.

A question on VCDS. There are no date stamps on these error codes. When an error occurs, does it stay in the system until it is cleared? So some of these codes could be from years ago? I have several codes including
16502 - Coolant Temp Sensor
17978 - Engine blocked by immobiliser
16567 - Fuel Temp Sensor A (G81)
16622 - Manifold Pressure / Boost Sensor (G31)
16497 - Intake Air Temp Sensor (G42)

I'm thinking the MAP sensor could have been the cause of my limp mode when under load at 3K+ rpm. Anyhow, great to finally see the codes and check these things.
 

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Older T5 vans don't time and date stamp codes, T5.1 onwards does.
Codes do numerous things - Some don't trigger a MIL light until enough faulty driving cycles have been performed.
Some soft-set a code which self erases if the fault goes away and enough fault-free driving cycles have been performed.
Some trigger a MIL light immediately a fault is detected.
Some trigger a MIL light and limp mode, which can be reset by turning the engine off and on. If too many of these resets are done, the limp and MIL become permanent until fixed and erased.
Some cannot ever be erased by repairing the fault and driving fault-free cycles, they must be erased manually with VCDS, (eg ALL airbag faults.)

Your other codes have no text attached, this is very important for a correct diagnosis! Best thing to do is save the codes on VCDS, then delete all of them and see what comes back.

16705 Engine Speed Sensor (G28) P0321 - Implausible Signal - Intermittent.

Can be caused by a failing sensor, or broken wires, chafed and shorting wires, and corroded connections. Worth checking while you're in there!
 

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Discussion Starter #7
Thanks Bluzie, really helpful info! I have saved and cleared all the codes. Will change the sensor and check the wiring connections. Going to do that work this weekend. If any codes return I'll post them in full. Cheers!
 

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Discussion Starter #8
Cleared the codes, then on my way to my workshop it conked out again. Let it cool and it started fine. Checked for codes.

1 Fault Found:

16706 - Engine Speed Sensor (G28)
P0322 - 000 - No Signal - Intermittent
Freeze Frame:
RPM: 2688 /min
Torque: 62.0 Nm
Speed: 34.0 km/h
Load: 51.4 %
Voltage: 14.44 V
Bin. Bits: 00000000
Idle Stabilization: 0.0∞KW
RPM: 1323 /min

About to replace the crankshaft sensor. Don't suppose anyone can tell me where this is on a T5 1.9? I'll have a good investigation myself but just thought someone could point me in the right direction. Not much info online for the 1.9.
 

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Discussion Starter #9
Found it. Sensor is located to the right of the oil filter housing. Cable runs around the filter housing and plugs into the socket on the left of the housing.
 
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