Alfa 2001 156 2.5 V6 24v AR32405 Bosch ME3.1 Misfire/Timing?

If you are not a PicoScope user and want advice with a diagnostic problem then post here. Forum members may be able to help.
Post Reply
User avatar
FioranoCars
TwoWaves
TwoWaves
Posts: 386
Joined: Thu Dec 13, 2012 11:26 am
Location: London, UK

Alfa 2001 156 2.5 V6 24v AR32405 Bosch ME3.1 Misfire/Timing?

Post by FioranoCars »

Hi
Another car from outside our core/familiar, so after some technical data please!

Got a car dropped in our lap by a friend, yes I have got 1 ... well ... he needs a favour ... anyway the car has been in a few garages over the last few months and at some stage had the Cam belt changed, another garage post this says timing is out. Don't know why the belt was changed and if problem existed before or due to this ... No invoices or more details about lambda sensors or other parts/tensioners etc, that's all I have.

It has lots of codes stored, with alternative descriptions as some seem to have conflicting meanings!? Any correction or confirmation of these would be good too:

Code: Select all

Petrol injection Bosch ME 3.1 Motronic [-/00>04/04] Euro 3

o P1130 Upstream 1-2 lambda sensors swapping (too lean to switch?) 
aka P1130 Lack Of HO2S Switch - Adaptive Fuel At Limit

o P0300 Misfires
o P0301 Misfire cylinder 1
o P0302 Misfire cylinder 2
o P0303 Misfire cylinder 3


o P0130 Upstream lambda sensor 1 signal
o P1135 Upstream 1 preheating resistance

o P0150 Upstream lambda sensor 2 signal
o P1161 Downstream lambda sensor 2 signal

o P1173 Mixture strength 1
aka P1173 Rotor Calibration Fault 

o P1176 Mixture strength 2
aka P1176 Cam Calibration Fault 

o U1600 Electronic key
Will get the MultiECUscan on it later, hopefully that can reset adaptive memory/fuel trims, as the generic tool used to pull these codes out did not cope well, and dropped comms with the ECU a few times. Maybe we'll be able to see some parameter data for insight?

Is there a manual reset for the fuel trims (battery off?) ?

We've quickly checked/smoke tested for air leaks, as it sounds like it's chuffing, both inlet and exhaust (not fully tested the vacuum system yet) and cleaned the engine ECU pins, plus added an earth strap to be sure the engine / ECU earth was good (had that issue before on this model). Spark plugs don't look too new (so not a recent repalcement), but tips appear good, a tad lean maybe, but not wet or heavy carbon deposits, arc'ing or other tell tales.

We're looking at doing some timing checks, but can't find any timing data or comparatives in the Waveform Library. Looked at Autodata and Haynes Pro, but neither have any data on the timing (changing the belt yes but not the actual data).

I'm sure we have a set of timing cam caps for this engine, but would like to get a Cam/Crank/Spark/Injector capture ... maybe even firstlook in inlet/WPS in cylinder and analyse it all first and hence decide if the timing is out for sure before spending 5-6 hours on a wild goose chase.

Anyone able to help with a sample crank/cam waveform from a 2.5 V6 24v (are the 3.0 or even 3.2 the same timing?)

I think the earlier AR32401 is the same timing as the 2001 onwards AR32405 (but not 100% sure!)?
2.5 V6 24v Applications:
1997–2005 Alfa Romeo 156
1998–2007 Alfa Romeo 166

Or just the raw timing data?

I do have the ECU pin outs, and will be checking the Lambda signals, as I understand the wiring is renowned for melting on the exhaust/water ingress/other damage, but don't think these are the source or cause of our chuffing noise!

Thanks in advance

Richard Lukins

User avatar
STC
Banned
Posts: 790
Joined: Sun Sep 13, 2015 2:10 am

Re: Alfa 2001 156 2.5 V6 24v AR32405 Bosch ME3.1 Misfire/Tim

Post by STC »

Richard
Multiple Random Misfires + DTC's related to Mixture control = Running Lean.

The upstream O2 is either the Cause or the Effect - The correct answer to that is the centre of your universe right now !!!

1. What are STFT and LTFT for both banks
2. Is this Manifold Injection or GDi
3. What is Manifold Vacuum measured with an analogue gauge at idle. How steady is the needle ?
4. Air Mass Signal Voltage at Ignition on and idle ?
5 Coolant Temp ?

Or put the kettle on - I will nail that in an hour or two :) :) :) I stand to be Corrected !!!

User avatar
FioranoCars
TwoWaves
TwoWaves
Posts: 386
Joined: Thu Dec 13, 2012 11:26 am
Location: London, UK

Re: Alfa 2001 156 2.5 V6 24v AR32405 Bosch ME3.1 Misfire/Tim

Post by FioranoCars »

Hi
Sadly no live data as yet, and not had a chance today to go any further, other than disconnect the battery tonight!

it's old school manifold injection, come on, it's 2001 !!

No Vac measurements, just did quick smoke tests, there was a small inlet leak, but repaired that for no difference, no MAF or other stuff, it was a quick look, all valid questions though.

About all day tomorrow, car is here and kettle on, you might even get to hear an A3 finally fire up too!!

Still want that timing data if anyone can help, as I will get a Crank and Cam with 2 other elements, and would be good to upload them with some form of judgement on their "state" for future ...

Best
Richard

User avatar
FioranoCars
TwoWaves
TwoWaves
Posts: 386
Joined: Thu Dec 13, 2012 11:26 am
Location: London, UK

Re: Alfa 2001 156 2.5 V6 24v AR32405 Bosch ME3.1 Misfire/Tim

Post by FioranoCars »

Just a quick update that I have found else where on the web some timing data, from apparently eLearn, can't verify it, and would like to if that's possible by anyone who has access to the the eLearn system ... please?

2.5 v6
Inlet opens (before tdc)9
closes (after bdc)47
Exhaust opens (before bdc)47
closes (after tdc)9

3.2 v6 (GTA)
Inlet opens (before tdc)8
closes (after bdc)55
Exhaust opens (before bdc)46
closes (after tdc)9

So don't have the 3.0 data either, which would be handy to know.
Also be very good to know how Alfa calculate the TDC from the crank - Is it the 2nd tooth after the missing tooth?
And to be cheeky, if eLearn or any other Alfa tech docs, explain the cam timing signal verse valve positions?

Anyway I hope this might help someone else one day!

Thanks
Richard

Martinjensen
TwoWaves
TwoWaves
Posts: 55
Joined: Wed Feb 13, 2013 6:22 pm
Location: Denmark

Re: Alfa 2001 156 2.5 V6 24v AR32405 Bosch ME3.1 Misfire/Tim

Post by Martinjensen »

From E-learn
Attachments
Timing angle.PNG

User avatar
FioranoCars
TwoWaves
TwoWaves
Posts: 386
Joined: Thu Dec 13, 2012 11:26 am
Location: London, UK

Re: Alfa 2001 156 2.5 V6 24v AR32405 Bosch ME3.1 Misfire/Tim

Post by FioranoCars »

Hi Martin
Many thanks for this confirmation.

Will try to get a capture later today and share.

Thanks
Richard

Post Reply