PH1 Continuous Cranking Non-Start

[Szabotage]

Not that it helps but, the gap to the reluctor ring should be about 15 to 20 thou or max of 0.5mm (20thou) i have had problems with non specific sensors not working then a genuine Bosch or Marreli works.
IMHO i think you will work it through but i feel that scanning for fault codes is a waste of time, it tells you what happened and not whats happening. get a good scanner that can display four or more inputs and watch the screen, if the ECU is getting the signal it WILL be displayed and therefore work and visa versa. Battery voltage is critical and constant cranking can push the volts too low, run a big slave battery whilst testing or a dedicated charger with about 70a capacity to keep the volts up.

Good hunting.

Thanks for confirmation on gap. We were using < 1mm ~ 0.4mm. The replacement purchased was a Facet version. Even if it is a bad sensor/gap, is it normal for the ECU to stop reading the data? In other words, shouldn't the ECU keep reading data, albeit in error? Situation now seems like the ECU is commanding relays to shut down the whole ignition/injection system.

Both TDC/CPS sensor units gave exactly the same readings. Data stream showing about 150RPM before dropping to zero even though starter was still turning at full speed. Manual states 250RPM should be expected. The data cuts out at precisely same time as voltage cuts out as measured at ECU and Relays.

Have tried every method, trickle charging the old batt, large amp slave batt, as well as a new batt. Wished it was an amp issue.

 

[Szabotage]

Yes keep the volts up.
It's still looking like it doesn't know the engine is turning and we keep coming back to the crank sensor.
You need to get Renault Clip plugged in for proper diagnosis.

One of the other changes is a alum LWFW. On visual inspection the tooth marks and reference point looked the same, and lined up with dowel pin. Again even if the sensor or flywheel were off, shouldn't the data continue to show during cranking? Does this point to an immobilizer issue, even though the immobilizer warning light is showing to be normal.

Another member mentioned a similar situation where engine out/in, immobilizer light showing normal, no start. tried a second good key and the car fired up. We don't have a second good key. (Our car has always had 2 sets of keys but one set never worked, and sets off immobilizer light.)

Which Version of the Renault Clip is the right one for the PH1 V6? time to invest in one of these. Renault CAN Clip Ebay

Thanks so much for everyone's input. A local owner has been kind enough to offer his working v6 for us to diagnose and get benchmark data. Hopefully this will help us find our gremlin.

 

[DaveL485]

[post]229285[/post] Data stream showing about 150RPM before dropping to zero even though starter was still turning at full speed.

Thats very low, I see 270-ish when cranking with a good battery and starter usually. Is it really that low or do you think its reading low and the crank is actually correct?

[post]229286[/post] One of the other changes is a alum LWFW

Aluminium isn't magnetic, how has whoever made the flywheel addressed the pickup points? I assume the notches in the notch-gap-notch-gap have some sort of ferrous material embedded?

 

[Jamesv6]

Some mention of Clip here in our knowledge base https://v6clio.net/manuals/faultfinding.pdf

 

[Brett]

Is the ring gear/notch pattern count the same on the new ally flywheel?

 

[rustedandrotten]

Just a thought......as the flywheel is alloy, the pick up works on changes in ferromagnetic effect of the teeth passing by, you will not be getting a pulse signal from the pickup if these are alloy as it will not be producing an EMF, basic physics. Your ECU will not be registering engine rotation or timing hence no start. You will need to fit an iron or steel inductor toothed ring to the flywheel to get the signal.

 

[Szabotage]

[post]229285[/post] Data stream showing about 150RPM before dropping to zero even though starter was still turning at full speed.

Thats very low, I see 270-ish when cranking with a good battery and starter usually. Is it really that low or do you think its reading low and the crank is actually correct?

[post]229286[/post] One of the other changes is a alum LWFW

Aluminium isn't magnetic, how has whoever made the flywheel addressed the pickup points? I assume the notches in the notch-gap-notch-gap have some sort of ferrous material embedded?

Just a thought......as the flywheel is alloy, the pick up works on changes in ferromagnetic effect of the teeth passing by, you will not be getting a pulse signal from the pickup if these are alloy as it will not be producing an EMF, basic physics. Your ECU will not be registering engine rotation or timing hence no start. You will need to fit an iron or steel inductor toothed ring to the flywheel to get the signal.

Is the ring gear/notch pattern count the same on the new ally flywheel?

The LWFW is one piece, integrated with billet teeth, which do match the OE pattern. I can't see ferrous material, and assumed it's embedded.

The reading is low. But it also lasts only for about a second and half. A possibility is that there is a lag and the reading is not reflective of true speed.

Would the ECU shut down power to the fuel pump relay after only a second and half if it wasn't seeing speed with in range?

 

[DaveL485]

[post]229320[/post] nd and half. A possibility is that there is a lag and the reading is not reflective of true speed.

[post]229320[/post] I can't see ferrous material, and assumed it's embedded.

Does a magnet stick to the teeth? No sticky magnet - no ferrous material - no/little flywheel signal

I remember back in the day I had an ally 21 flywheel and it had steel inserts visible in the top, literally flat head bolts screwed in

Given the time you have put into this issue so far i'd defo spend a day swapping the flywheel back to see if it fires up. I'd bet good money it starts.

 

[DaveL485]

Saying all that though, the Helix site claims the bespoke flywheels are steel not Ally

"FLYWHEELS
All Helix Autosport flywheels are made from Chromium Molybdenum Steel. They are made to exact tolerances using O.E specifications and fully balanced."

 

[DaveL485]

I can't make out a reset point on that flywheel either, there is a reset point right?

 

[rustedandrotten]

Change flywheel back :approve: Invariably if something fails to function after you have change something, the 'something' tends to be the most likely point of first reference as to what is wrong! If it then starts you know where to be looking. If the flywheel is alloy you will not get a proper signal from the transducer which is looking for changes in the magnetic field it produces in the form of lumps of ferromagnetic material and air spaces alternating and a reference void to give it a datum, what you are probably picking up are spurious signals from the starter bendix ring which is toothed and ferromagnetic!!

 

[ed_harland]

I can't make out a reset point on that flywheel either, there is a reset point right?

Assuming there is enough ferrous metal to trigger the pickup, I think Dave is right. I can't make out the 'missing tooth' so the ecu has no reference for tdc, so apart from not knowing when to spark and squirt it wont know the rpm either.

 

[Brett]

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[Brett]

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[Brett]

Is the ring gear/notch pattern count the same on the new ally flywheel?

There’s your problem then. A different pattern with missing notch.

Is it a TTV item? Most strange if it is as no one has had a problem with one before.[/quote][/quote]

By the way, I VERY much doubt it’s an ally flywheel or the nice new friction plate won’t take long to eat through it with out a steel face inserted.

 

[DaveL485]

[post]229330[/post] so apart from not knowing when to spark and squirt

....and we all need to know that, right

 

[DaveL485]

[post]229336[/post] Is it a TTV item?

Unless TTV have started engraving "HELIX" on their flywheels, I would imagine it's a Helix one, what with it having "HELIX" etched on it (lower left, 8 o'clockish)

 

[Szabotage]

I can't make out a reset point on that flywheel either, there is a reset point right?

Thank you everyone for your comments.

It's a Helix unit and does have the cut out, have edited image so it's easier to see. Matches the OE unit. I could be and probably am wrong about it being Alumn.

But for sake of brainstorming, let's say it is Alumn and the reset point is wrong. Would the ECU cut out after just 1.5 seconds of trying to pick up?

That's what the multi-meter is revealing @ ECU/Relay pins. It's as if the ECU is stuck in Prime mode rather than Run mode with it's command. ECU is shutting down the fuel pump as well as the portion of the ECU that receives engine speed data.

Version 183 Renault CAN Clip just arrived. Will install the software and give it a read tomorrow. Hopefully that reveals more.

 

[rustedandrotten]

If it was Aluminium, there would be no signal to the ECU showing the engine revolving so it would go into 'stand by'

 

[Brett]

[post]229336[/post] Is it a TTV item?

Unless TTV have started engraving "HELIX" on their flywheels, I would imagine it's a Helix one, what with it having "HELIX" etched on it (lower left, 8 o'clockish)

Sorry, only just read the post and wasn’t looking that anally at my phone when checking the picture. Just noticed the glaringly obvious point that it’s not ally so don’t get too tied up with the whole voltage not reading it due to that reason thing.

Will keep shut from now on. :salut: Best of luck with it. Seems like you’re getting there with it. I have a range of flywheels if anyone needs info.