Technical No ideas left - engine runs hot after conversion
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Technical No ideas left - engine runs hot after conversion
These posts could be the holding the answer. The temp light glowing dimly suggests it is getting a low voltage, rather than just being turned on. So it is expecting a temp switch, but its got a temp sender. Swapping the ones from the original engine seems like a good idea.
I have just noticed that in the factory workshop manual, the sensors K35/K45 are the wrong way round in the connector type section.
The sensor K45 is a 2 pin junior timer connector and the switch K35 is a 1/4" spade type.
The sensor K45 is a 2 pin junior timer connector and the switch K35 is a 1/4" spade type.
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OP
OP
The fitted sensors are the Original ones that cam from with the 1.2 MPI engine.
It starts glowing first but it's bright after a while.
I think I'm gonna fit a gauge in that hole.
As the Sei has no tempature gauge.
As everything else work, fan and so one I guess nothing can go wrong... and it's just a fault.
Yes, but you need to know what instruments were fitted with the donor car.
Makes sense. But a better idea yet is to test the sensor/switch. If it's the kind that operates a warning light, at some temperature it'll just go to continuity. If it's the gauge type it'll show a progressive change in resistance as the temperature increases. You'll get a proper sensor with the new gauge: if you use a T piece and fit the proper switch you can have a gauge and the warning light. (A good thing.)
It's not a fault -- you're just using the wrong kind of sensor!
Hi, I know this may sound nonsense ,but, did you check or replace water pump? Some water pumps they have a plastic "fan" type and they are prone to fail due to high temperature runs, I know for a fact as VAG group cars when they have overheating issues and 90% of them are due to plastic water pump models. Don't know about fiat but that's just me trying to help, remove water pump and check if spins freely with one hand holding the pulley, if you don't want to remove water pump, there is another way to test, remove the outlet coolant hoose that goes on the radiator and with a bucket ready to drain water, turn engine On for a couple of seconds and see if you have any water pressure, if NOT, water pump it's dead. Hoppe this helps buddy 
You need to use the ones that match the ECU and car, as the engine is from another!
OP
OP
The used ECU came with the donor car
I will check the resistance of the sensor this week to see if there's a big change between cold water and boiling water.
Does anyone know the size and thread of the sensor?
If someone does I can order a gauge right away
I will check the resistance of the sensor this week to see if there's a big change between cold water and boiling water.
Does anyone know the size and thread of the sensor?
If someone does I can order a gauge right away
But the rad, fan switch and fan belong to the car. Don't assume that the ECU will communicate along the same wires as the Sei.
It would appear that the temp is being controlled ok by the rad switch, but the light is being confused as the sender expects a gauge.
Options:
A) Replace lamp sender with the one from the original engine, giving a too hot warning only.
B) Fit a gauge and wire to the currently fitted sender.
C) Fit a T-piece and fit both senders, adding a gauge and keeping the warning light.
NUGGY
New member
the fan switch and dash temp sensor do not go through the ecu, the rad switch goes through a relay and turns the fan on at a predetermied temperature and the warning light goes straight to the dash this too is set to come on at a set temp, the ECU only controls the running of the engine on the pre 2000 cars i have this set up on my car and it has run ok for 7 years and 60000 miles (only the temp sensor in the manifold goes to the ECU)
OP
OP
That's what I thought.
you should have removed the temp senders from the engine that was in your auto and fitted them to the replacement engine.
your auto red light display is expecting the same too hot warning sender switch the new ECU probably could have tolerated the old coolant temperature senders temperature dependent resistor values
there is no fault or problem with engine your warning display will do a peter and wolf display
your auto red light display is expecting the same too hot warning sender switch the new ECU probably could have tolerated the old coolant temperature senders temperature dependent resistor values
there is no fault or problem with engine your warning display will do a peter and wolf display
OP
OP
I got it somewhere so I will look it up.
Also a gauge is ordered so I can hook them up the end of the week.
Also a gauge is ordered so I can hook them up the end of the week.
OP
OP
Well, the Gauge is in.
Cables have been soldered and everything is in place.
Now I have to wait till Wednesday for a adapter to mount the sensor in the cilinderhead.
Cables have been soldered and everything is in place.
Now I have to wait till Wednesday for a adapter to mount the sensor in the cilinderhead.
OP
OP
Well the sensor is connected and working like a charm.
Drove the car up and down the terrain to get to 95 degrees.
The fan kicks in at that temp and cools it back down to 90 degrees,
So that's done.
Just need some way to make it look cool, but that's after MOT
Drove the car up and down the terrain to get to 95 degrees.
The fan kicks in at that temp and cools it back down to 90 degrees,
So that's done.
Just need some way to make it look cool, but that's after MOT
