Yamae

At the connector pin#3 while cranking. Or simply use a oscilloscope renting/buying.

011011011

Hopefully will acquire an oscilloscope later this week.

In the meantime I have established (by acquiring a spare coil) that the coil isn't likely the problem, as it also makes no difference when feed is lifted to it. Strangely enough there is no difference to engine running when you unplug all of the coils on the offside bank

Does this call into question the offside bank camshaft sensor? Or still the IGF feed to the ecu?
Perhaps the remaining unchanged BP capacitor...

swear this car is possessed.

Yamae

Why don't you read the code at the DIAG connector? You don't need any special equipment only a jumper wire is needed.

011011011

Tried it. Doesn't work. Incidentally is it the VSC light that's supposed to flash? Don't appear to have an engine symbol on the dash?

011011011

With the ignition in the ON position the following values are recorded on the IGT wires at the unplugged ignition coil connectors with a handheld oscilloscope :

1. 5.4 (mV)
2. 4.4
3. 5.4
4. 3.5
5. 9.6
6. 5.1
7. 6.4
8. 1.9

All exhibit a similar pulse waveform. Why is number 8 so low in comparison to the others?

aptoslexus

Factory spec on the igniter wires:

dicer

If that is in the manual it is written badly. At the end does it mean replace both coil and igniter?

aptoslexus

I think it just means the connector. If you don't have the voltage at the connector and the rest of the diagram has you checking the circuit back to the ingnition switch, that condemns the connector but not necessarily the coil.

011011011

Thanks Aptos. That diagnostic refers to the pin 1 12v supply. That is fine on all 8 ignitor coils. As is the Ground on pin 4.

Values above are measured on pin 2 - the IGT trigger from the ECU. Not sure whether they are supposed to be "firing" in the iGN ON position with no engine rotation or whether the pulse picked up is just noise from ecu? Seems a very low voltage (mV)?

Hopefully the engine will run again today now it's cooled down overnight and I can get some readings on the IGT and IGF whilst it's running.

Beginning to wonder if it's a valve timing problem on the OS bank

Additional info:

7 of the 8 coils have been swapped for used spares and problem has not changed at all so not suspecting it's a coil issue now.

All the capacitors in the ECU are now changed.

011011011

Also, can anyone advise on this please?

Thanks

011011011

IGF 2 signal reads as regular clean pulse

IGF 1 signal reads as noisy peaky trace

(both backpinned at coil plug)

Unplugging other IGF1 coils individually makes no difference to trace

Engine running on NS bank only, unplugging OS coils makes no difference to engine running.

If anyone knows exactly which ECU terminal the camshaft sensors are wired to on a '98 european spec that would be most helpful, as the pinout I have for the 2000 model doesn't seem to be correct?

aptoslexus

Diagnostics at the ECU: USA model. I don't know if there are any differences on European models.

aptoslexus

Crankshaft position sensor

011011011

Thanks Aptos

Diag only mentions one Camshaft sensor; is there not two on the v8?

Camshaft pulse at ECU seems a bit ropey. Crankshaft pulse is fine.

(Which would explain why it really doesn't like hot starting as that's common with CPS)

aptoslexus

There's only one, on the left side. The manual calls it "left bank camshafts", confusingly.