ABF Fault - Cylinder 1 Recognition Sensor (G145) - Updated findings

I see, cheers. So I can rule the hall sender out then despite the fault code? I just don't get the mk3 digi managment, it's doing my nut in. I don't know how you have the patience for all the looms you do lol

Anyway more investigation this afternoon.

- G145 fault code still showing (intermittent)

- Re-checked continuity on the dizzy plug and it seems to check out ok still.

- Stripped off the wiring for the sensors. The loom has been previously repaired once I stripped the outer sheath off and a bunch of heat shield (as shown in pics below) but has been spliced and looks ok to me. The 3 pin for TPS wiring was spot on and looked untouched, as did the wiring for the hall sender but the 2 pin for up on the throttle body had new sections of wire soldered in.





The earth for the Dizzy seemed to disappear down into this plastic sheath with a bunch of other earths (is that something added by you RJ?)



The two ring earths on the side of the head cleaned again




RJ I know it's impossible to diagnose completely but how certain would you say the crank sensor is at fault here, is it worth splashing out on a genuine one to try and solve this? I really don't know where to go from here and funds are pretty tight the next month. It fires up fine just runs like a dog at random intervals. Sometimes it's ok from cold until it gets hot, other times it just misses like hell from cold. It HONKS of fuel as well haha so it's running rather rich.

 

No you cannot rule it out. If the ECU 'sees' the return signal as plausible then the fault will not be present. It is that simple.
It is unlikely to be a fault on sensor G28 as that would have also flagged a fault a long time ago, along with the engine disabled.
Sounds like the loom was built correct, for what you checked and the ECU diagnostics is reporting a genuine fault.

In your clip the engine is running a bit rough and misfiring, though so there maybe more than one concern in operation.

I will have to check but I may have an ABF camsensor/dizzy you can use as a second test.
Pity you are some distance as these concerns would have been solved a long time ago.

 

Cheers Toyotec. To be honest the misfire is a lot worse now since that clip, it was fairly tame then. Cheers I would appreciate that - from the sounds of things do you think a different dizzy is the way to go then?

Thanks

 

You have a fault on G145 (no signal) which will need 'shutting up' before proceeding. Once ECU is happy it is in control ( no fault codes), if the concern of rough running is still obvious, then you have a mechanical problem, such as leaky manifold gasket, leaky injector o ring etc.

 

Right...I disagree from a control logic standpoint. If the sensor is not functioning, then unplugging will indeed make no difference to engine operation. The engine will run as I suggested, without knock control, reduced ignition timing function and no individual injection. This will contribute to the concern.
Seriously you should rectify this concern first as it can cause driveability concerns. The subjectivity of it works "well" with the CAS unplugged I would disagree based on the operational reasons why this component is there, as well as my own background during testing and evaluating multiple vehicles.

I appreciate you are looking at this from what you have picked up outside ECU logic, however that is not how diagnostic logic works I am afraid. There are fault thresholds that accumulate to determine if a fault is present, intermittent, pending, plausible, implausible and so on.
So a fault path via G28 is different from a fault path from G40/145. 'No signal' means the ECU sees no square wave on pin 44 over 720 CA, key on engine running.

Mechnically they can also leak from the injector seals and the PCV as well. One injector o' ring was found missing on my own car, which contributed to a lean misfire on the cylinder. My car incidentally runs an aftermarket CKP from ECP that works brilliantly.
I am more than happy to send a working CAS sensor/Dizzy for trial and even simulate the fault on a vehicle that is down here.

 

Cheers chaps, on the phone at the mo but will read this all carefully when I'm home tonight.

 

Because you have driven a similar engine’d car for many miles and it did not misfire to you, makes the contribution of others less significant ?
I read your opinions but struggle to see the method for eliminating the factors that are either driving to contributing to the thread title.
By the way I am not worried about anything, for me this is a really just a small issue not even worth a page of troubleshooting IMO possibly fixed in very quick time if the vehicle was in front of me.
The checks I suggested do not take hours, heck I could build a SEM'd, mapped and working ABF conversion in that time lol. The suggestions are to help speed up the process, as you would want to do if this car were on garage rates or if you were in a research environment, where this issue would be a PITA/ obstacle to real data gathering.

What we know so far.
We believe the ECU pins are intact and correct and do make good contact loom to ECU.
Unless you say your loom is at fault, then we assume this was built correctly.
From a diagnostic and calibration perspective, the CKP is in good working order.
We know with T68/44 intact back to pin (0) on the hall sensor there is no signal being returned to the dizzy reported by VW calibration and its diagnostics.

Unknown
Condition of CAS (for fault).
ECU A/D convertor for Pin 44 malfunction.
Engine mechanical air leaks that can enlean a cylinder ( poor manifold gasket, Injector seat, massive air bypass local in plenum i.e. servo pipe, damage PCV diaphram)

Plan of action (unless there is better one)
Send working CAS sensor.
The use of spare ECU can be considered pending CAS test and other validations.
Attempt to recreate concern on local vehicle and evaluate.
If electronic validation pass, move to mechanical causes.


None of us know from a distance what is driving the poor operation as seen in the video clip, but it is not coincidence, that we do have a clue, that very important ECU fault is being logged. I also know from experience in a very involving drive cycle to and from work, the fault in the thread tiile that can affect drive towards misfire. I have seen it occur on both ABF/VR6/AQZ engined vehicles which had very intact VW looms.
You need to rectify the fault and then deep dive on any remaining concern else indeed this can quickly turn to 4 pages + of no joy.

That is my 2p.
If you guys want to use the components or the suggested process of elimination for distance, then my offer is still there and can be taken up via pm

Hope it all works out.

 

Wow well this thread has certainly expanded since I last left.

First off a massive thanks to both of you for your inputs! I'm sure if the car was in the hands of either of you the problem would be solved in minutes however as I have stated electrics are not my fortay and the ways of the ABF are new to me. The past couple of months have been a complete ball ache with the conversion but I must say without the likes of this forum I would be entirely screwed. What is puzzling is the engine came from a perfectly running car, I was driving it around for a few months. It seems a few components have died since being transplanted into the Golf.

RJ the crank sensor I got was the one you listed above. I don't think the car would actually be drivable unfortunately even if it was road worthy. Regarding the measuring blocks I did notice the coolant temperature seemed pretty far off what the dash read when warming up to temp but nothing else especially was noticeable. Again I may not have the eagle eye for it though. I will check ecu pin 33 for continuity at the weekend as well as for any air leaks

Toyotec I'll drop you a PM RE: Spare Dizzy

Again, thank you.

 

G145 Fault similation follow-up. Gad's reference car.

Following my promise,

Gad came around with his Mk2 Golf with ABF engine controlled by Digifant 3.2 (BE) PCM.



This vehicle is what I call the "reference car" and is part responsible for the How ABF your MK2 thread.

First we interrogated the ECU to check for any faults since the last check over a year ago.




Next the vehicle was started and an extended idle was performed. Group 1 measuring blocks were observed. Everything looked as expected and the next step was to drive the vehicle to assess feel.

My subjective thoughts:

• Tip-ins at 30% throttle, second gear and 1500rpm were reasonably responsive with a progressive ramp from 2-3K at WOT.
• With 4th selected, you could still pullaway from 10mph with minimal judder.
• Lambda sensor voltage as expected, oscillating between 0.2-0.6v at idle loads, 0.1-0.7v at part load and 0.85v steady at WOT.
• Drive feel all OK after 25 mins of mixed driving.
• Coolant was 90 deg C and airbox temp was 32 deg C

Now that vehicle feel was established next step unplugging the CAS while the engine was running (simulating failure).



Instantly this familiar code popped up!



Along with a CKP fault (G28) (but the engine was still running)
With the sensor disconnected clearing the codes made no difference to the recorded faults.
Plugging in the CAS allowed both codes to clear, unplugging made then both come back.

The car was driven, with the CAS unplugged for 25 mins, in the similar manner to when the CAS was connected.
My subjective thoughts:

• Initially tip-in at 30% throttle, second gear and 1500rpm resulted in some lag with more throttle required to achieve required acceleration.
• Ramp at WOT from 2-3krpm linear making vehicle feel flat.
• As the vehicle was driven, the tip-in became more hesitant, with some shuffle also was present nearing 25mins of driving. I am sure this would have become worse with more time (which in this case was limited). Unfortunately, lambda voltage was not observed during these manoeuvres.
• 2-3krpm ramp at WOT still linear.
• Pullaway in 4th from 10mph struggled as if there was a lack of engine torque.
• Coolant was 89 deg C and airbox temp was 35 deg C

Plugging in the CAS allowed both faults to clear.
Drive feel was restored as in first drive.

jmsheaham got your pm

 

Nice, many thanks for that info Eddie and for taking the time to find that info out.

Interesting that unplugging a known good hall sender sparked a G28 code too for the crank sensor, I wonder why mine isn't doing that as well. Also interesting that the car was drivable, all be it down on performance with it unplugged. Before I take the dizzy out this weekend and test the pins RJ mentioned I may try just shuffling the car about on the drive to see if the car is driveable, I suspect not to be honest. It's rather annoying that it's not taxed or MOT'd for a proper test drive to confirm.

2 other factors I was thinking about recently too - the Ibiza had a really bad rocker cover leak previously. Owner told me he had changed the gasket after the car kept missing but didn't clean up the oil mess left behind. I've since replaced the gasket again and thoroughly cleaned everything but I wonder if that has had a terminal effect on the hall sender. Seems odd to have died during the switch of body shells though (although the ABF ISV did so it's possible! Now running the original 8v mk2 one). Also after discussing airleaks above I do have suspicions about the brake servo - it works but I can hear a faint hiss with turning the engine off which I need to investigate. Will cap the outlet on the manifold temporarily to rule it out.

Now to check out how the dizzy is removed.

 

Afternoon chaps - just a small update on findings to follow up:

RJ - Round plug pin 14 to ecu pin 33 checks out for continuity

Eddie - Removed the dizzy so should arrive with you over the next few days

I haven't found the source of servo 'hiss' yet but removing the brake servo to manifold pipe and capping it made no difference. Obviously needs rectifying but it shouldn't be a major contributing factor with the missfire at present.

Will see what comes back when Toyotec kindly checks the dizzy and go from there.

 

jmsheahan's dizzy/CAS tested on known good working vehicle.

So here we go...

The dizzy arrived on Tuesday in one piece.



Today I made a request for the 'reference' car and gad agreed for me to use it to complete this exercise.

So off with the 'good' dizzy.



an on with jmsheahan's




VDS was connected and fired up




And the fault screen was brought up.


Once the engine was started, the fault was triggered straight away and would not go away.

Reinstalled gad's cam sensor allowed the fault to clear.



Therefore jmsheaham, your dizzy or CAM sensor is confirmed dead...

Next steps:

• Find a CAS/Dizzy.
• Investigate and hardware issues.

Many thanks to gad for the use of his daily ABF vehicle for these investigations

 

Absolute champ, cheers Toyotec (and Gad for lending the car as a test ). Replied to your PM.

Out of interest did Gad's car misfire and run like a dog too with my dizzy on it? Or was it just a fault code showing?

New dizzy should arrive ASAP with any luck and I'll report back if it's solved.

 

No problem, happy to assist. Also thanks again to gad for extending the club sprit and lending his car as a surrogate for this test.

No it did not misfire is in your video clip.
What was observed was on tip in from cold there were flat spots were as on gad original the transients were progressive of cold start and drive.
Once you get the replacement dizzy fitted, if there are any further issues, then it will not be controls but mechnical.
Then you you can take me up on the other pm offer

 

I see, thanks Toyotec.

The second hand dizzy arrived on Friday so I set about fitting it today. Results:

- G145 Fault code is now gone as far as I can tell (scanned 3 times)
- No other fault codes found
- Fired up first time

However the problem is is still very much apparent. ...

I did take it for a quick spin up the estate and it was spluttering, missing and generally unhappy about running before cutting out. It did restart again but reluctantly. So upshot is no fault codes now however still unsolved.