voltage to Camshaft sensor code 8.

[obiwanwasabe]

Hi all,

I have fault code 8 showing and am just going through the voltage checks to the sensor, I am getting signal from the sensor when it is disconnected so am looking at the voltage and earth feed. The earth, which I believe is the white wire is reading good but there is only .22 volts on the live wire (orange) with the ignition on and also with it cranking, this is also the same at the ECU output (d5), should I be getting battery voltage or, as is sometimes the case, 5 volts and any ideas where I could be losing it?
Occasionally I see code 9 appearing after I have been cranking it for a while so could it be that the voltage feeds to both of these are linked and the problem is in the ecu?

Hoping someone can help
Nick

[Steve_M]

There is no voltage spec in shop manual for the TDC sensor, you need to be working from the resistance of the sensor and continuity of the harness back to the ECU.

Check resistance at sensor 4 pin plug (pins 1 + 2), should be 800-1300 ohms - no resistance = new distributor
Then confirm the same sensor resistance at the ECU end of the harness (pins D7 + D8) - no resistance = break or short in harness.

Resistance at ECU = New ECU required.

[Steve_M]

https://drive.google.com/open?id=1u_...JZfD_FL0J-CaiD

[obiwanwasabe]

https://drive.google.com/open?id=1u_...JZfD_FL0J-CaiD

Hi Steve,
I was looking at the cam sensor, behind the top cam sprocket, and pins d5 and d6, as I believed that was where code 8 was sending me as, are you saying that it is probably the tdc sensor in the distributor I should be looking at and that being why it throws up code 9 occasionally. My previous experience with cam sensors always taught me that the 2 pin ones had voltage and earth and the three pin ones were hall effect. so I treated it as a 2 pin std cam sensor, but it makes sense to me that is can work without a pos feed, sensing the raise in resistance (ohms), which I have from the cam sensor. You reckon it's time to check the tdc sensor? The Engine starts and runs and if I can get it past idle by reving as I crank it the eml comes on and idle goes up to 2k when I throttle it back, This car has been in dry storage for 4 years and was ok when I put it in storeage.

[Steve_M]

DTC 8 is TDC sensor (In distributor)

DTC 9 is CYL Sensor (Behind camshaft sprocket)

http://www.u-ukhbc.co.uk/troubleshooting.htm

"This car has been in dry storage for 4 years and was ok when I put it in storeage. " - I would put my money on a knackered ECU. Capacitor leakage and board damage

[obiwanwasabe]

DTC 8 is TDC sensor (In distributor)

DTC 9 is CYL Sensor (Behind camshaft sprocket)

http://www.u-ukhbc.co.uk/troubleshooting.htm

"This car has been in dry storage for 4 years and was ok when I put it in storeage. " - I would put my money on a knackered ECU. Capacitor leakage and board damage

Thanks Steve, full resistance read at the ecu, will check the cam sensor pins today, the ecu is like new inside, no swelling from the capacitors and no leakage although one of the brown ceramic capacitors looks to have overheated at some time and looks to be on the track for the output pins for the tdc sensor. I have cleaned and checked all the connectors from the distributor and car now showing code 9 all the time now and intermittent starting, so will do the same from the cam sensor to the ecu today but I think it is the ecu. Time to take a drive up to the ecu doctor in Plymouth.