1.6 L problems

[SimonR]

Are the plugs I need to remove, the ones circled in the attached photo?

Thanks
Martin

Those are the ones!

[D813YBB]

Thanks

I'll follow the steps recommended by Gary and report back.

Regards
Martin

[D813YBB]

Update

I’ve disconnected the ORFCO valve and noticed a vast improvement, with the car much smoother now. The hunting has disappeared.

However the fast / slow revs at idle is still present. I had a fiddle with the idle screw on the carb yesterday but have been unable to remedy this problem. The throttle cable had free play in it already.

As a possible related issue, the temperature gauge on the car has been reading lower than normal for some time. I had put this down to the thermostat being stuck open as I had this problem once before. So I replaced the thermostat with a new one yesterday, but the gauge is still reading lower than normal.

Could there be a link between the idle and the temperature readings? What would cause the low temperature reading?

[G Force]

Update
Could there be a link between the idle and the temperature readings? What would cause the low temperature reading?

Yes, in particular if the gauge is sat at 1/4 even when you turn the ignition on first thing, as this would indicate an open circiut in the coolant temp sensor or its wiring.

If the gauge works normal but just reads low this could be a poor connection between the temp sensor and the fuel ecu, or a faulty sensor.

Check that you have a good connection at the coolant sensor plug, then the large multi plug on the n/s bulkhead near the washer resevoir as this plug is notorious for poor connections and corrosion , the finally the fuel ecu plug.

If you have a multi meter you can check the resistance of the coolant sensor, with a hot engine expect a reading of 150-250 ohms. You should have continuity between the sensor and ecu on the pink/green and pink black wires, but you need to also unplug the ignition ecu to take an accurate measurement.

[D813YBB]

Hi Gary

The temp gauge slowly moves up the scale as normal after start up but it never makes to its usual position (just before halfway) unless at standstill. It drops back down to just above the quarter mark when travelling at speed.

Is the temperature sensor the plug that sits in the radiator about 2/3 up from the base on one side with two wires going into it?

If so I may have a spare taken from a diesel van that I can swap it with.

[G Force]

Hi Gary


Is the temperature sensor the plug that sits in the radiator about 2/3 up from the base on one side with two wires going into it?

If so I may have a spare taken from a diesel van that I can swap it with.

Hi, No that is the radiator cooling fan switch. The coolant sensor is the one in the lower casting of the thermostat housing.

Gary

[D813YBB]

Thanks for that Gary, I'll investigate further one evening this week.

I don't suppose you'd like to hear about today's little experience with the car; driving back from Carlisle I suddenly hear a sizzling sound from the dash board and next thing the rear wiper decides to switch itself on. But it doesn't do the standard three wipes and stop. Oh no it just keeps on going while I press the switch on and off. Eventually a combination of pressing the on off switch and wash wipe switch gets it to behave itself, before it does it again a few minutes later then back to normal for the rest of the trip.

It was a good thing it was chucking it down with rain at the time. What would my BMW driving boss be thinking if he was in the car!

[G Force]

I don't suppose you'd like to hear about today's little experience with the car; driving back from Carlisle I suddenly hear a sizzling sound from the dash board and next thing the rear wiper decides to switch itself on. But it doesn't do the standard three wipes and stop. Oh no it just keeps on going while I press the switch on and off. Eventually a combination of pressing the on off switch and wash wipe switch gets it to behave itself, before it does it again a few minutes later then back to normal for the rest of the trip.
!

Bizarre carry on that, you dont' have a water leak getting into the drivers footwell when it rains by any chance do you?

[D813YBB]

Well, I couldn’t believe it this morning. Driving to work both idle and temperature gauge were rock steady with the temperature reading at the normal position on the gauge even at high speed. The strange thing is, I haven’t done anything, as I was waiting until the weekend to investigate further.

The fact that both corrected themselves together must point to the source of the problem to be the temperature sensor?

I was planning on dismantling, cleaning and re-assembling it tomorrow.

Gary,

The rear wiper has behaved itself since, but I never had water leaking into the dash or footwells.

[G Force]

The fact that both corrected themselves together must point to the source of the problem to be the temperature sensor?

I was planning on dismantling, cleaning and re-assembling it tomorrow.

Gary,

The rear wiper has behaved itself since, but I never had water leaking into the dash or footwells.

The reason I was wondering wether you had water in the footwells was; It sounded like the sort of problem that rain water getting into the rear wiper switch or relay might cause. I was thinking also that because disconnecting the orfco valve fixed the surging, this points to a short circuit in the throttle pedal switch. The switch is on the throttle pedal bracket also in the area where rain water ingress could leak.

As for the temp gauge and idle problem correcting itself does point towards a bad connection in the temp sensor wiring or the sensor.

Gary

[G51 NAV]

The temp gauge slowly moves up the scale as normal after start up but it never makes to its usual position (just before halfway) unless at standstill. It drops back down to just above the quarter mark when travelling at speed.

I haven't read all the way though this thread but that particular symptom usually means the stat's stuck open

[G Force]

I haven't read all the way though this thread but that particular symptom usually means the stat's stuck open

Hi John apparently a new thermostat has been fitted recently to try and rectify the temp gauge reading low, so I think hopefully thats now out of the equation.

Gary

[D813YBB]

Update

The car is continuing to perform in a stable manner, although I still haven’t had the opportunity to check the temperature sender.

I would like to thank all those who offered advice to solve the problem especially G Force (Gary).

Just to clarify, a new thermostat was fitted in an attempt to fix the problem but without success.

[D813YBB]

Update

Well I knew I'd spoken too soon when I said the car was stable. The temperature gauge and idle started acting up again after a few days. I get temporary periods where it is stable.

I've had a fiddle with the connections on the temperature sensor but it all seems in good order.

However things have got worse recently with following:

windscreen wipers (front and rear) are now coming on at random or when indicating left or right or flashing the headlights accompanied by a sizzling sound in the dash. I get momentary dips in or loss of power from the engine which sometimes coincide with flashing the lights or indicating, but not always.

I activate the windscreen washers and the rear wiper also goes on as well.

The stranger thing is all these things seem to happen during periods of erractic idle and dodgy temperature readings.

The car is becoming a real problem for me now.

[G Force]

windscreen wipers (front and rear) are now coming on at random or when indicating left or right or flashing the headlights accompanied by a sizzling sound in the dash. I get momentary dips in or loss of power from the engine which sometimes coincide with flashing the lights or indicating, but not always.

I would be very concerned about the sizzling sound that you describe as it suggests some part of the wiring is short circuiting, causing "arcing" this unfortunately is how fires can start.

You really need to try and find out the exact area where the noise is comming from. (I know that can be easier said than done.) Make sure the orfco wires that you removed are taped up and clear of the hot engine.

Loose or poor earth points can also be a cause of the type of problem you are having. There are earth points on the front bumper mountings, one on the N/S A post, one in the boot, large battery cable to gearbox, and a small one in the centre back of dash. I may of forgot the odd one so if anyone else knows of others please let D813YBB know.

Gary