24 replies to this topic

[NickB787]

I am trying to find out if there are any other vauxhall's which run without cam sensors apart from the z22se

[siztenboots]

z20let doesn't seem to use the cam sensor , more as a reality check than essential

[slindborg]

the 20XE did... it then got updated to the "ecotec" XEV and gained a cam sensor which followed to the LET's too. most pre 1995 stuff ran without.

[NickB787]

the 20XE did... it then got updated to the "ecotec" XEV and gained a cam sensor which followed to the LET's too.

most pre 1995 stuff ran without.

I am interested to see what ecu's have run without it and if they are cracked

[siztenboots]

Motronic 1.5.5 used in lots of GM and Fiat / Alfa stuff This may help with wiring loom , reference voltages and functional description http://www.amtgarage...nic M1.5.5 .pdf

[rabidh]

I'd be worried that the older engine managements that don't need cam sensors didn't manage sequential fuel injection? From what I found with my ECU, having fully sequential makes a big difference to low-down torque when it's timed right. It probably doesn't matter so much at high revs though. Just to add - the ECU linked above shows a cam position sensor? But I guess it could probably be cracked to run without. Assuming you used the whole Z22SE ignition module, there is actually an output on it which raises and lowers exactly like a cam position sensor (it's created based on which one of the two plugs connected to each coil sparks first - which will be the one which is on the compression stroke). Has anyone tried just connecting it up? edit: Maybe not the right place, but I finally found the PDF on it again: http://www.motor.com...?article_ID=853

Edited by rabidh, 10 March 2010 - 11:27 AM.

[slindborg]

you cant do sequential injection without some sort of phase sensor. Not sure how far the thread about getting the existing coil pack sensing to work with other stuff is going.... there is a thread or two on Z22SE.co.uk about it.

[John Faulkner]

z20let doesn't seem to use the cam sensor , more as a reality check than essential

the camshaft sensor is needed when using standard mangement, otherwise your ecu will go into 'safe mode' restricting the revs.

[rabidh]

What's the shape of the camshaft sensor wheel on these ECUs? The LE5 one uses a relatively complicated pattern - but that is just because it's controlling cam phase. I'd guess for an ECU with both crank and camshaft sensors, all that matters is that the camshaft sensor reads +5v at TDC for one rev, and 0v for the other rev? If that's the case I would have thought you could just angle-grind a semi-circle out of the end of the exhaust cam and use a sensor on a bracket inside the cylinder head?

[siztenboots]

z20let doesn't seem to use the cam sensor , more as a reality check than essential

the camshaft sensor is needed when using standard mangement, otherwise your ecu will go into 'safe mode' restricting the revs.

from my testing it made no difference to performance or ignition timing / fuel trims

[The Batman]

sizeten are you saying you are running without one then?

[siztenboots]

sizeten are you saying you are running without one then?

to eliminate the sensor and wiring loom it was one of the things we tried for extended mileage, I could not get it to raise a MIL code, it probably just substitutes a default value.

pretty sure it is 100% crankshaft timed and fuelled.

[techieboy]

pretty sure it is 100% crankshaft timed and fuelled.

That would be handy.

[siztenboots]

thinking about it , the crank trigger wheel turns every rev , whereas the camshalf wheel has less teeth and only turns once every 2 crank revolutions, so probably would not tell you much.

[slindborg]

thinking about it , the crank trigger wheel turns every rev , whereas the camshalf wheel has less teeth and only turns once every 2 crank revolutions, so probably would not tell you much.

it only tells you that X cylinder is at TDC and to therefore base all fuel calculations and which injector/plug to fire when if using sequential and individual plug fring.

[siztenboots]

thinking about it , the crank trigger wheel turns every rev , whereas the camshalf wheel has less teeth and only turns once every 2 crank revolutions, so probably would not tell you much.

it only tells you that X cylinder is at TDC and to therefore base all fuel calculations and which injector/plug to fire when if using sequential and individual plug fring.

sorry , as you say , the odd or even cylinder firing, its wasted spark , so just fuel ?

its got a 50% chance , but is there a missing trigger on the cam to tell it which

Edited by siztenboots, 10 March 2010 - 01:31 PM.

[slindborg]

there only needs to be a lobe at a 90degree quadrant of the cam shaft (two rotations of the crank = one rotation of the cam). tbh the lobe can be anywhere as the ecu software can be set to accept any marker/crank poistion setup (assuming you can get at the code lol)

[rabidh]

tbh the lobe can be anywhere as the ecu software can be set to accept any marker/crank poistion setup (assuming you can get at the code lol)

This is what I reckon - but I guess the question is whether the Motronic earlier mentioned will (or can be made to) cope with that. It has both crank and cam sensors, so it's a good start.

edit: I guess we're a bit off-topic now

Edited by rabidh, 10 March 2010 - 01:41 PM.

[siztenboots]

tbh the lobe can be anywhere as the ecu software can be set to accept any marker/crank poistion setup (assuming you can get at the code lol)

This is what I reckon - but I guess the question is whether the Motronic earlier mentioned will (or can be made to) cope with that. It has both crank and cam sensors, so it's a good start.

edit: I guess we're a bit off-topic now

z20let timing wheel ( note the balancer shaft drive gear )

[rabidh]

What does the cam sensor trigger wheel look like though? or is it built into something so you can't see it?