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ST170 Cam Sensor (Zetec?)
Dave Bailey - 6/3/11 at 08:23 PM

Not such a good day in the garage today... I have had the ST170 engine running but a bit rough plus not with the cam sensor enabled.. I thought I would just check the sensor output and make sure I had wired it correctly to the DTA ECU.. I just couldn't get a signal from the sensor and there was so much noise... The crank sensor seems fine.. I am just wondering if the ST170 is a magnetic or hall effect sensor.. There are different inputs on the ECU for each.. The ST170 cam has 5 sensor lobes... I have wired the screen to the ECU ground and not the sensor ground but as I say this seems to work for the crank sensor....

It could be me having trouble with the scope but the cal signal seems o.k.....

Any advice?

Dave B

[Edited on 6/3/11 by Dave Bailey]


MakeEverything - 6/3/11 at 08:30 PM

Doesnt the screen connect to the EDIS module? (Assuming it has one!)


coozer - 6/3/11 at 08:34 PM

Mine runs fine without using the cam sensor. Are you using the oem inlet to after market/home-made?


Dave Bailey - 6/3/11 at 08:54 PM

Running throttle bodies... with DTA ECU.... I need to run the cam sensor because the DTA will run the variable cam timing....

Dave B


coozer - 6/3/11 at 09:10 PM

I dont think so, the VVt is variable off the oil pressure. I just use a relay to switch mine at 3K and off it goes.

IMO the cam sensor is for sequential injection...

[Edited on 6/3/11 by coozer]


Dave Bailey - 6/3/11 at 09:28 PM

Yes sorry your right about the sequential injection but I am pretty sure the DTA needs to know where the cam is so that the Variable cam timing works correctly.. They told me I needed to connect it.. The Cam Valve is also driven from the ECU.. On that subject I seem to have read conflicting things about the cam valve.. Does it run off 5V or 12V?

thanks
Dave B


coozer - 6/3/11 at 09:34 PM

The VVT switch on top of the engine needs 12v. I tried 9v but it wouldn't budge. I then checked a Focus wiring diagram to find it runs off a 20 amp fuse.

I use an output on my ECU to ground a relay at 3K, this sends 12v up and its off!

This run was using carbs with very small mains, before jetting, thats the drop off you see at the top end.



IMO running TB's, which I am now, doesnt need the cam sensor.

[Edited on 6/3/11 by coozer]


Dave Bailey - 6/3/11 at 09:41 PM

Coozer,
Have you measured the current drawn by the valve? DTA insist that the ECU will supply enough current... I am concerned though if it is anywhere near 20A.... I don't think the timer connectors are rated anywhere near that! I wonder if the 20A fuse was also supplying other components....

Dave B


coozer - 6/3/11 at 10:04 PM

Yep, it was supplying a few things. The valve has 1mm wiring so is a chunky bit of kit.

My ECU (MS) wasn't up to the job so it switches a relay that I run off a 10 amp fuse. The relay gives the ecu good protection.