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A while back I posted about a “fuel pressure” issue because of occasional hard starting.
After putting an odb reader on - come to find out, my heat sensor was throwing all sorts of weird readings and I think that is what was causing the intermittent starting problems.
Since I’ve got about 220k on it now, and since the thermostat housing was seeping slightly, I replaced the whole thermostat.
But that required using the new wiring adapter. And the adapter fit on the lower 4 prong plug-in - and also to the heat sensor and lower sensor.
And it all all went great - and it starts fine now and I’m getting good temp readings with obd reader. BUT, do I just cut the leads from the old temp sensor that goes across the top of the engine over to the mass air flow sensor??
Since that sensor is made onto the lead and that is part of what plugs into the maf plug, I’m puzzled as to what to do with it.
i dont understand how you can get a different thermostat housing that doesnt work with the previous sensor
They've made several styles over time - to correct earlier weaknesses. Going from certain older types to the new style requires the adapter (as I understand it). And the new adapter DOES work fine - I'm now getting proper temp readings and the car is running fine again - except I don't know if a person is supposed to just cut off the old temp sensor or what - since it is wired into the MAF plug in.
I am NOT getting proper MAF readings, but it was doing that before and is a separate problem.
You have that adapter plugged into the totally wrong spot. It does NOT plug into the mass air sensor.
Go to the drivers side of the car where the thermostat is and there will be 2 sensors in the thermostat. Follow the wiring back. Depending on the production date of the car they may go into a 4 pin connector like that, or they may stay as 2 pairs of wiring going into the harness. If they go into the 4 pin connector then you need that adapter to install the newer style thermostat.
"So what’s your year and Trim (Base/S/D/JCW) are you?"
It is a 2011 Base Countryman.
Originally Posted by WayMotorWorks
You have that adapter plugged into the totally wrong spot. It does NOT plug into the mass air sensor.
Go to the drivers side of the car where the thermostat is and there will be 2 sensors in the thermostat. Follow the wiring back. Depending on the production date of the car they may go into a 4 pin connector like that, or they may stay as 2 pairs of wiring going into the harness. If they go into the 4 pin connector then you need that adapter to install the newer style thermostat.
Originally Posted by MannyJimenez
So what’s your year and Trim (Base/S/D/JCW) are you?
That is whats puzzling to me, too. The way that old temp sensor laying there in the picture is MADE into that 4-wire plug that also sends 2 wires to the MAF is how it was wired when I bought the car. When I replaced the thermostat housing, I unscrewed the temp sensor out to fully remove the housing.
The thermostat had the original 4 wire plug at the back of the base of the housing - and the new one I got took the adapter to go from the 4 wire harness plug to the 2 wires to the temp sensor and 2 to the thermostat (I think??).
But that is also what made me ask - does a person just cutoff the old temp sensor? Since it's two wires are made into that 4 wire plug shown in the pic? Or are you saying someone before me somehow got it plugged in like that and it was never supposed to be that way? Other than the check engine light coming on 20k miles or so ago - the car runs great. It had bouts of starting hard, but the new temp sensor seems to have cured that fine. OBD Fusion was reporting engine temps of 220+ all the time when the old sensor failed - but the engine never truly overheated or ran low on coolant. And it reports fine now with the new thermostat housing/sensor installed.
