Poor running e36 (M52B25) - codes now read

[NiceCupOfTea]

Hi all,

My e36 323 has been poorly sick for a little while now, idles fine, revs fine over 3k or so but very flat and unresponsive in between. Also slow to catch when starting.

Finally managed to borrow a Peake tool and read these codes (still present after resetting and going for a short drive):

(Table 11)
41 camshaft position sensor
d4 vanos mechanically stuck
0c throttle position sensor
d6 vehicle speed signal not present

This all seems to tally - camshaft position sensor the slow starting and gutless feel if the ECU is having to "guess", sticky vanos - well my brother's 328 had the same thing but it stuck the other way, fine normally but a lumpy idle and breathless at the top end.

Not so sure about the throttle position sensor, it does feel a little slow to react to imputs.

vehicle speed signal - I have had ABS/TCS lights on for a few months, they came on before and the garage reset them after cleaning up a couple of plugs. I'm guessing these are related?

Plan of action? I know the camshaft sensor is relatively easy with the right spanner and the vanos solenoid is in the way. What's the vanos likely to be? knackered solenoid or something more mechanical?

Where is the TPS located? Will try cleaning up some connections.

Not sure where to start on the speed signal. Does it take it from one of the wheel sensors? Can't imagine they have all failed...

[E-bmw]

NiceCupOfTea said:

Hi all,

My e36 323 has been poorly sick for a little while now, idles fine, revs fine over 3k or so but very flat and unresponsive in between. Also slow to catch when starting.

Finally managed to borrow a Peake tool and read these codes (still present after resetting and going for a short drive):

(Table 11)
41 camshaft position sensor
d4 vanos mechanically stuck
0c throttle position sensor
d6 vehicle speed signal not present

This all seems to tally - camshaft position sensor the slow starting and gutless feel if the ECU is having to "guess", sticky vanos - well my brother's 328 had the same thing but it stuck the other way, fine normally but a lumpy idle and breathless at the top end.

Not so sure about the throttle position sensor, it does feel a little slow to react to imputs.

vehicle speed signal - I have had ABS/TCS lights on for a few months, they came on before and the garage reset them after cleaning up a couple of plugs. I'm guessing these are related?

Plan of action? I know the camshaft sensor is relatively easy with the right spanner and the vanos solenoid is in the way. What's the vanos likely to be? knackered solenoid or something more mechanical?

Where is the TPS located? Will try cleaning up some connections.

Not sure where to start on the speed signal. Does it take it from one of the wheel sensors? Can't imagine they have all failed...

Cam shaft sensor is what it is & as you say, a simple fix.
As it the TPS, just change it, you can check it with a simple voltmeter or even using "live readings" on most code readers.
Speed comes from the diff housing, feel free to check wiring/contacts/plugs/voltages etc.

[NiceCupOfTea]

Cheers.

Presuming that genuine BMW is the way to go? Over £100 for a camshaft position sensor seems harsh though!

[NiceCupOfTea]

Just been having a fiddle with the car. There are two pots on the inlet side, I think the larger one is to do with the ASC-T, and the smaller one on the throttle body itself (the smaller one) is the TPS.

I tested both of them and they both seem to check out with values I saw in a YT video - resistance across terminals 1-3 was 4K, resistance across 1-2 varied between 1.5K and 4K depending on the position of the pot.

I did notice that the inlet pipe had a big split in it so that's something else to sort.

At the moment, plan is to to the camshaft position sensor and the inlet pipe, reset the codes, and if the TPS code comes on again replace that if it is a sensible price.

Hoping to get INPA set up at some stage when I have some time to read the ABS/ASC-T codes in more detail which will hopefully give me a lead on those lights and possibly the speed signal code.

Vanos, God knows. I'll sort everything else first though.

[NiceCupOfTea]

Update.

Retested the codes and found that the TPS one has disappeared. This is weird. It's an easy fix but I'm not going to buy one until I've got the new inlet hose on in case it's related.

I have just replaced the camshaft position sensor with a genuine BMW one and been up and down the road after clearing the codes. Bizarrely, the only code that came back on is the sodding camshaft!!

I guess the speed sensor didn't have time to rear it's head as I only went 100 yards, but I wonder if pulling and refitting the vanos solenoid whilst changing the camshaft position sensor was enough to get that working? Or maybe it will come back on after a longer drive.

Any thoughts? I have cleared the codes again and will go for a longer drive in a bit to see how it feels. Could be wiring I suppose... Plug felt seated OK, and it is genuine BMW so hopefully the sensor itself is OK.

Any ideas how to test the VANOS solenoid properly? I put 12v through it but it didn't move. Does the polarity matter? The piston sat about 1cm down from the end of the thread. Couldn't push it back. Would a knackered solenoid cause a "mechanically stuck" error? The piston it pushes in the head moved freely.

Bloody thing!

Edited by NiceCupOfTea on Wednesday 21st February 14:44

[SebringMan]

I know on the E46 M3 if the system detects something wrong with the VANOS it will 'freeze' the VANOS in the last known position until the fault dissapears and stays off. When mine went it threw a couple of VANOS codes.

There is a chance your seals have broken down but it's looking unlikely.

What code reader did you use? IME INPA and iCarly always bring back more results over the generic types.

One way to test the VANOS is to do the VANOS test on it. DIS can do this.

[NiceCupOfTea]

It's a Peake one that goes in the round socket. I have INPA and a cable do just need time to set it up...