4.6 Landrover/Range Rover cam/crank waveform please.

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4.6 Landrover/Range Rover cam/crank waveform please.

Postby modo » Sat Jun 01, 2013 1:21 am

Hello just wondering if anyone has a known good cam/ crank waveform for a 1996 4.6lt V8. I have a customer who had his backyard mate do the engine up on this car. It has very low vacuum and a slight miss at very light throttle all other sensors seem fine, good spark and fuel , my gases have hi HC and O2 readings I think he has the cam timing out but not sure asked for wf on other web sites and haven't had any response seeing you guys would see more of these I hope I'm in the right place to post this request.
Thanks Dom
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Re: 4.6 Landrover/Range Rover cam/crank waveform please.

Postby Chris_W » Sat Jun 01, 2013 9:49 am

Last one of these i had in bits i can't remember seeing a CMP sensor? It was a long time ago though.

If I remember right you'd struggle to get the timing out though, it's pretty obvious. These have hydraulic liters though, were they drained and were the valves touched?
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Re: 4.6 Landrover/Range Rover cam/crank waveform please.

Postby modo » Sun Jun 02, 2013 11:52 pm

Thanks Chris, this vehicle apparently had a full rebuild by his mate while he was in hospital I don't know any more information other than that and it was sent to me because of very slight miss and low vacuum. Here is the capture I have taken.
Many thanks Dom.
Attachments
1996 Range 4.6lt V8 CKP CAS COIL & Injector Voltage.psdata
(2.4 MiB) Downloaded 245 times
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Re: 4.6 Landrover/Range Rover cam/crank waveform please.

Postby KimAndersen » Mon Jun 03, 2013 11:51 am

Hi Modo

It's a odd looking waveform you got there.

The information i have of this type of engine is - that the camshaft sensor should produce four pulses for every two revolutions of the engine.

Is there any diagnostic trouble codes from the PCM !!!

Regards
Kim
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Re: 4.6 Landrover/Range Rover cam/crank waveform please.

Postby onboardtech333 » Mon Jun 03, 2013 2:19 pm

Trying to get a customer who has one in for you so I can grab a quick reference.
I was pretty sure they were good about setting a correlation code for timing being off though.
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Re: 4.6 Landrover/Range Rover cam/crank waveform please.

Postby Chris_W » Mon Jun 03, 2013 8:28 pm

Well goes to show what I remember.... :roll:

So having done a bit of research my next question is this - were the timing chain and sprockets changed? Because if they were there are 2 different sprockets for the cam. It mat explain your odd trace. Though I could be wrong again, it happens...a lot. :oops:

Still wouldn't explain the running problem though?
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Re: 4.6 Landrover/Range Rover cam/crank waveform please.

Postby modo » Mon Jun 03, 2013 9:47 pm

Thanks again for your responses I have put this capture up on other sites and still haven't got any response. Unfortunately this bloke has gone back to his farm in the far north so I won't be seeing it again for many months/years and as far I know he was told a full rebuilt and there were no codes in memory. I would still be interested for future reference. I properly have worked on maybe less than a dozen L/rovers in 26years so any input would be a big help.
Much appreciated Dom :mrgreen:
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Re: 4.6 Landrover/Range Rover cam/crank waveform please.

Postby Valhalla » Mon Jun 03, 2013 11:24 pm

Indeed, Landrover recognised that the sprockets could be interchanged, and that the signals would be wrong for the respective controllers. If my memory serves me correct, the old camshaft sprocket would only output one pulse per 2 engine revolutions, whereas that latter sprocket was four pulses per 2 engine revolutions (confirmed with RAVE this evening). The later engine (I believe) would be the one that outputs a DTC of P0340 if the wrong cam sensor ring is used.

The main difference between the pre-1999 engine and the post-1999 engine is the engine management computer. Early one is a GEMS controller, whereas the later ECM is a Bosch Motronic (pretty easy to spot from the markings). So that would be a first check, to see if this engine is a genuine 1996 unit or not.

Kim is right about that cam sensor signal though - as well as being twice the frequency of pulses, the Bosch system should have 3 short pulses and one long pulse per two cycles, as this gives the phase of the cylinders for the ignition timing. What you have there seems to be something else altogether. Maybe the "mate" has sourced a third type of pulley? :roll:

That is definitely an early crankshaft sensor signal, 36 teeth, rather than the Bosch Motronic 60 teeth (including the missing teeth positions)
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Re: 4.6 Landrover/Range Rover cam/crank waveform please.

Postby modo » Tue Jun 04, 2013 4:09 am

Thanks guys for all your wisdom ,I wish I posted here first, I will contact him and let him know he may have fitted the wrong gear and to check with the original one.
Many thanks again Dom :D
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