Sorry, was referring to mk 1 re sensors; some water in exhaust is normal; not sure where to put the temp gauge sensor on the mk2 but on the mk1 the temp sensor is on the drivers side of the cylinder head on the back and if the same type of head is used there may be a blanking plug; alternatively some temp gauge kits have a sensor that fits in one of the coolant hoses.....
Technical Possible overskimmed head - Help...
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Technical Possible overskimmed head - Help...
WhiteSei. I'm not the greatest with elec stuff so not sure what you mean. I spliced into the 2
wires going to the sensor and connected a meter. I thought I could measure the current as it
varied per the haynes manual explanation and the water temp rising once the engine was started.
Would this approach work? When I tried to measure the current with the meter, as I say the fan
came on. The temp warning light *only* came on when I disconnected the sensor completely which
makes sense as the ECU now believes the sensor is faulty I assume.
I suppose what I am really after is a method I can use to verify the sensor is working as it should.
TinyTim. I will look for blanking plug and let you know.
wires going to the sensor and connected a meter. I thought I could measure the current as it
varied per the haynes manual explanation and the water temp rising once the engine was started.
Would this approach work? When I tried to measure the current with the meter, as I say the fan
came on. The temp warning light *only* came on when I disconnected the sensor completely which
makes sense as the ECU now believes the sensor is faulty I assume.
I suppose what I am really after is a method I can use to verify the sensor is working as it should.
TinyTim. I will look for blanking plug and let you know.
WhiteSei. I think I get you now. By connecting an ammeter *across* the wires I effectively shorted the sensor circuit which means a large current flowed (as the sensor resistance was bypassed) and the ECu concluded the engine was very hot! Hence fan comes on! Well, at least I know the ECU-to-fan bit is working! So if I took my ammeter and measured 2 points on one of the sensor wires that should work to read the current? I assume the voltage between the two wires (set by the ECU) doesn't vary so nothing to be learned by measuring voltage except that it is set correctly. Any idea what voltage the ECU sets just out of curiousity? I'll try measuring the current tomorrow and see what happens.
Update: Took the car to get the irish MOT (NCT) today. On the way there I had the coolant sensor disconnected. So the engine and temp warning lights were on as was the fan, continuously. Drove about 5 miles and it went well. Got my cert (just needed a visual with tyres from test done prior to head gasket blowing). When I tried to start the car to come home it cranked but no ignition! Thought I was screwed. Let it sit for a minute and it fired! On road no power and something clearly wrong. Also noticed that engine light went off while temp light stayed on. I had been checking continuously for engine heat and it was nowhere near danger levels. Eventually had to pull over as had hardly any power. Car idled fine. Plugged coolant sensor back in. Temp light went out. Drove home fine. Not sure what to make of all this but I think the next most pressing thing is to get a temp gauge installed as I have no idea what's going on when I'm driving.
TinyTim - I looked for the opening for the gauge sensor but didn't find anything. Reckon I'll have to fit a gauge sensor into one of the hoses.
TinyTim - I looked for the opening for the gauge sensor but didn't find anything. Reckon I'll have to fit a gauge sensor into one of the hoses.
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I dont have a clue what the values are. But yes, a voltmeter is used across the +ve and -ve and an ammeter goes in-line. One measures pressure the other measures flow.
Maybe without the temp reading the ECU went into limp home mode.
As for gauges, you could put 50mm dia oil pressure, volmeter and temperature into the gubbings box by the gear lever.
Maybe without the temp reading the ECU went into limp home mode.
As for gauges, you could put 50mm dia oil pressure, volmeter and temperature into the gubbings box by the gear lever.
WhiteSei. Not sure I understand what you mean by the gubbings box? Can you tell me more? Quick update: I took the coolant sensor out and measured resistance while heating it up in a pot of water. Here's what I got: 40C - 1.16 50C - 0.81 60C - 0.59 70C - 0.42 80C - 0.31 90C - 0.23 100C - 0.18 That's pretty close to what the haynes says. Haynes says the thermostat opens between 85C - 89C and is fully open at 100C. Does anyone know at what temp the fan should come on? I ask because even tho the sensor seems to be working fine, the fan has never come on but does come on if I bypass the sensor. I'll drive it tomorrow and see what happens!
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Took the car for a test drive today. Did about 20 miles. Runs pretty good. A couple of times it felt like there was a lack of power and once it shuddered a little but seemed to recover from these. Am hoping these are quirks of the car clearing out crap from the last head gasket failure! I'm not convinced the head gasket is fully tight but I'll continue to monitor the oil and watch for signs of coolant. Thanks everybody for the help.
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Im probably mistaken (not unusual 
) I thought all puntos had a radio cassette size pocket in the dash down by the gear lever (which is usually filled with a storage box) and the radio head unit mounted higher up in the dash.
My car has the standard non working CD changer in the lower slot. But the space could easily take three aftermarket gauges.
Regarding that temperature sensor - its probably ok - not really much to go wrong. But, the wires going to it might have a corroded connection affecting the resistance values..
) I thought all puntos had a radio cassette size pocket in the dash down by the gear lever (which is usually filled with a storage box) and the radio head unit mounted higher up in the dash. My car has the standard non working CD changer in the lower slot. But the space could easily take three aftermarket gauges.
Regarding that temperature sensor - its probably ok - not really much to go wrong. But, the wires going to it might have a corroded connection affecting the resistance values..
