Hi, I,ve posted this one before but still have same problem. My Rover 214 K series engine runs so erratic that when starting from cold it's great, first turn and away we go but the problem is the RPM remains at 1500 rpm for some 10 miles. A good "thrashing" sorts it. Fuel consumption 18-20 mpg though! I've changed engine and coolant temp sensors to no avail. Re-set stepper motor & usual plugs, dizzy etc. All HT & LT leads A OK or replaced! Had a new head gasket recently, new thermostat at same time, oil and coolant new & A OK. No sludge. I use the vehicle on short trips of some 4 miles to work & university runs for my kids of 250 + miles Blackpool to Sheffield & back etc. with no problems once or twice a month. The heater blows normally warm/hot after a 1/4 mile or so but temp gauge reads 0 & remains 0. Only after a motorway thrash does the temp gauge read normal. Heater normal. (No cold/hot air). Idle though still high, 1250 rpm approx. Even after the university run the idle is some 1250-1500 rpm. Any suggestions?

if its any cosolation my 220 coupe does the same just sits at 1250 hot or cold ive been told the problem could be the idle screw the throttle body or 1 of the pipes going from the inlet manifold to the ecu that may have some oil contamination another weird 1 is the timing could be a tooth out

Is it spi or mpi?
If the rpm is remaining high and you're getting poor mpg figures, then almost certainly the ecu thinks the engine is cold and is pouring the fuel in. There could be a number of reasons for this, most usually faulty temp sensor or thermostat.
You've changed both of these but there could be a bad connection or the stat could still be trouble.
As your temp guage is remaining low most of the time I would suspect the thermostat being stuck open or non-existent.
Was it replaced by you or a garage?

To check the thermostat, start the engine from cold and as it warms up feel the large top and bottom radiator hoses going to the engine.
The top one normally warms up quick but the bottom one should remain cool until the engine gets up to normal temperature, after which the stat will open and that hose will suddenly get hot, as coolant circulates through the rad.
If it slowly gets warm like the top hose, then there is a problem with stat for sure.

Check on that and let us know.

If temp gauge goes cold when on the move but rises up to normal when stationary then it sounds like a failed thermostat to me.

David,
I recently fitted a new thermostat in my 214i, and found out, thanks to the parts chap that there are 2 types of stat. One has a plastic housing, the other a cast one , the stats are different might be worth while checking yours.

Daniel will know better than me, i think hes told me before that one is for the ECU and the other for the gauge on the dash

Hi David, I got your pm.
Did this problem happen after the head gasket change or was it happening before?
I got that you've changed the thermostat 3 times but did you try the check I suggested? This will rule it out so that other things can be checked. Let us know