1994 850 temperature gauge goes up, won't start

Post by **rspi** » 06 Oct 2014, 07:21

Where did you get the ETC from? I would really try to get one from a Volvo parts supplier, a Volvo sensor.

Volvovlo · Post by **Volvovlo** » 06 Oct 2014, 19:50

The mobile mechanic came round today and spent an hour looking at the car. He pulled the computers out and cleaned the connections, and took the camshaft position sensor off and the plastic connector casing around the wires broke up. He couldn't get the car started, and reckons it's either the camshaft position sensor or one of the computers that are faulty, and told me the temperature gauge has nothing to do with the car not starting. What are your thoughts?

Post by **rspi** » 06 Oct 2014, 20:16

If the cps has a bad plug it will stop the car from starting. Did he check for spark? If the temp gauge is getting a bad reading it is likely sending a bad reading to the computer which would cause the car to have starting issues.

Have you tested the cluster? You can jump A7, press the button 3 times to put it into test mode. The temp will go to the bottom of the red, the fuel will go to 1/2 of a tank, the speedo will go to 70mph, the tach will go to 3,500 rpm's and the odo will tick a little at a time like the car is moving along.

Volvovlo · Post by **Volvovlo** » 06 Oct 2014, 21:20

Did the test on the cluster, nothing happened. Maybe I'm doing something wrong? I'll call up the scrappie for a second hand camshaft position sensor, and see if that works, if not then I'll get the ECUs, if it doesn't work it's probably time to sell it

Post by **precopster** » 07 Oct 2014, 04:57

The computer box is the one with the stickers on it in this photo if you are even remotely interested in cleaning the ECU contacts.

Volvovlo · Post by **Volvovlo** » 07 Oct 2014, 14:13

Yes I managed to find that, and clean the connections. Still no start

Post by **Atis** » 08 Oct 2014, 03:02

If the ECU reads wrong temperature values, it can easily cause no/hard start issues, as the air/fuel mixture is corrected based on temp readings. It could be that not your temp sensor is bad, but the wiring somewhere.

Post by **E Showell** » 08 Oct 2014, 07:50

No start that isn't spark related can often be caused by faulty ECT readings. When I change the ECT, I always also change the thermostat since they work in tandem and a fried thermostat can mess up your ECT readings.

Volvovlo · Post by **Volvovlo** » 08 Oct 2014, 17:22

I don't have a thermostat (According to my mechanic) They took it off (Apparently) when they changed my radiator because they thought my thermostat cracked the old radiator (I don't see how).

Just changed camshaft sensor, still doesn't start

Whats an ECT? Is it the same as an ECU? I can't find a second hand ECU for it

Post by **E Showell** » 08 Oct 2014, 18:00

ECT is Engine Coolant Temperature sensor. No thermostat is probably not helping you. Put one in.

1994 850 temperature gauge goes up, won't start

Re: 1994 850 temperature gauge goes up, won't start