Car turning over but not starting

[DarrenM]

Went to fire her up yesterday but she's just turning over and not catching. Havent had chance to have a good play but what are the usual symptoms? Cam/Hall sender?

I had this on my V6 and luckly Carlos up the road had a spare knocking around that cured it.

Car is not with me at the mo but where is the exact position on ABY?

cheers

[Dpicariello]

I had this about a year ago. It was the cam hall sender which is in the worst possible place behind the cam sprocket.

Here's the thread I made during the saga

Hall sender replacement

[Rusty]

There's also the crank sensor, I've had problems with this.

[Flat on my back]

Oh pooo...

Got a 2 channel scope if ya need some probing done...you need to make an appointment though, as i'm booked for fixing a friends alarm system (house) in the next few days...should have been a plumber...

[DarrenM]

cheers guys, that Hall sender thread sounds a right pain the in ****, didnt know they were so tucked away. where's the crankshaft sensor btw?

Carlos, yeah, could prob do with a second pair of eyes if you're free at all.

cheers

[Rusty]

Down on the gearbox where it mates to the engine, about level with the ABS pump.

[UrS4boy]

Went to fire her up yesterday but she's just turning over and not catching. Havent had chance to have a good play but what are the usual symptoms? Cam/Hall sender?

Car is not with me at the mo but where is the exact position on ABY?
cheers

The two most likely suspects are the fuel pump and the cam position sender (CPS).
A CPS failure will throw a code (blink code 2113 for the AAN probably the same for the ABY).

How to blink out the codes

If you get the 2113, then you know the answer = CPS

Link to info about the CPS

The CPS is very important because without a signal, the fuel pump relay is not triggered, and as a result, neither are the injectors, etc.

Link to the importance of the CPS to triggering the J17 FP relay.

Link to one CPS replacement prodcedure

Link to a complete pictoral on CPS replacement (on an AAN) using the group buy BBHME301.

Of course, if you don't get any codes, it still could be the CPS but it could also be the fuel pump.

Here is a procedure to check the fuel pump on an AAN (you can use the same idea).

It's very unlikely that it's the crank sensor.

[DarrenM]

Nice one, those links are well useful and much detailed pic wise.

cheers for that

[pixsaudisex2]

mine did this the other day it was the fuel pump can you hear it running.

[DarrenM]

I'll check laterz, what am i listening for a "whirrr" noise when ign' switched on?

[pixsaudisex2]

yeah and when cranking ( dont know where the fuel pump is on a coupe though but get somebody to turn the key and put your head near you should hear it easily) an year a wirrrrrrrring noise.

[S2central.net]

Yes and no... The fuel pump only runs when the engine is running - the relay is controlled by the ECU.

You can test quickly if the cam hall sensor is working with an LED (same one as for blink tests) by placing it across pin 2 and 3 on the 3-pin connector at the sensor - you should see it blink when you crank the engine... One blink for every two crank revs.

You will need a scope to see if the signal is the right shape and occurs at right time wrt crankshaft position signal. Search for that here and you'll see scope plots I captured - sorry just not had time to write this all up properly on s2central...

[Flat on my back]

Btdt...

To be continued...

[Jas11n]

Agree above as Paul says. You can't hear the fuel pump when just turning the ignition on. Other models of the era primed their pumps, but not the I5 20vT.
If you can hear a "whirring" noise, it'll be your aux water pump.

[Bowlerwell]

If it's the Hall Sender it should pop up on VAG com.