Crankshaft position sensor issue

Technical Area Engine, Transmission, Exhaust etc
2

I am still trying to get my 2002 1.8 VVT back on the road, but I am not having much luck.

My latest attempt included fitting a new crank position sensor, but, although the engine cranks over easily,  the engine will not start.

When I turn the key, to start the car, there is absolutely no movement of the rev counter needle. (Which was exactly the same with the old sensor).

Can anybody tell me what sort of readings I should be seeing on a multimeter, at the three wire clip that comes off the harness ?

I think I have a good ground connection, but, with the  key in the ignition on position, what should I be reading on the power and signal connectors ?

Any advice or help would be most welcome.

 

p.s.

The Haynes manual says to gap the sensor at 0.5 to1.5 mm.

I have tried so far at 0.6 and 0.9 mm

3

You would just be looking for a peak of a few volts from the sensor side pf things. It was some years ago that I checked one, therefore just try each wire with another in turn with a multimeter set to say 20volts.

With regards to the loom side, there should be around 5 dc volts from the ecu.

4

Thanks for your reply Drumtochty.

I have not yet checked on the sensor side, as I had nobody to help this afternoon, so i was focussed on the loom side.

On the loom side, with the multimeter set at 20 volts, I found no combination of wires that gave me any indication that power was coming from the ecu.

So, if you don’t mind, I have a few questions.

1.When the engine is cranking, but not firing, should I be seeing some minimal movement on the rev counter ? I have seen a couple of you tube videos which suggest I should be seeing up to 200 rpm.

  1. Would the absence of the 5 dc volts from the ecu, combined with the absence of rev counter movement, be an indication of a dead ecu, or am I missing something much simpler ? ?

Again, thanks for your help.

 

Phil. 

 

 

5

I do not have a mk2 here at the moment. I will try to find one and check.

6

A bit of an update, as I am learning as I go.
To make sure I was using the multimeter properly, I did a couple of tests, using the car battery and an AA battery, to check DC voltage, so I am fairly happy that the multimeter is working/calibrated correctly, and that I know how to read it.
Now I am happy that I have a good ground on the loom side.
Unfortunately, I can now see that the voltage from the ecu, with ignition on but not cranking is as low as 69 millivolts.
I suppose that my next step is to check for continuity on the power line.

Phil.

7

 

Could be something other than crank sensor. Most ECU’s need to see revs to fire injectors 

8

Any suggestions as to what to look for next ?

I have checked the fuel pump.

I have checked the fuses.

The timing is  O.K.

I have checked the injectors and replaced the O rings and seals.

I have good compression on all 4 cylinders.

69 millivolts on the crank position sensor power supply seems very low. Now confirmed at 69 with the ignition key at the On position, but not cranking, and still 69 when the engine is being cranked.

 

 

 

 

 

 

9

Another quick update.
I was discussing my car problems with my son, yesterday evening. He asked me what do I see on my EOBD / OBDII screen.
When I said that, since I could not get the engine running, and there were no warning lamps visible, I had not bothered connecting it. He suggested I hook it up anyway.
I hooked it up this afternoon, and I could not get a connection.

Am I correct in thinking that this is one more indication of a dead ecu ? I will have a look tomorrow, to see if i just have a loose connection, but once I get the ecu out, is there anything I can test ?