Engine temperature

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monoi
Posts: 134
Joined: Mon Nov 02, 2009 10:15 pm
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Engine temperature

Post by monoi »

Hi,

My engine runs fairly cold according to the gauge, ie the needle indicates just after the blue zone (about 1/4 of the range) instead of the middle as I would expect.

How can I check whether its a sensor/gauge issue or an engine issue? Would that affect fueling? Emissions are in range according to the last mot testing.

Also, and maybe it is related, but when I accelerate from standstill and the engine was idling, there is a distinct hesitation which sometimes feels like the engine is just about to quit.

Any ideas?
635 Csi highline 3/89
Pod
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Re: Engine temperature

Post by Pod »

You could try grounding the sensor wire. That should cause the gauge to go to maximum and confirm it is working. Additionally, confirm that you have a thermostat fitted. Without one, in this cold weather, the engine could struggle to reach operating temperature.

I find that replacing the ignition components can often make a marked difference to performance. It never hurts to replace the distributor, rotor arm, plugs and leads. If this makes no difference, you will have a spare set for the future😉
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Brucey
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Re: Engine temperature

Post by Brucey »

monoi wrote: Sun Feb 18, 2018 5:59 pm
Also, and maybe it is related, but when I accelerate from standstill and the engine was idling, there is a distinct hesitation which sometimes feels like the engine is just about to quit.

Any ideas?
If you have not checked it recently, I's suggest that a common cause of this hesitation is a badly adjusted TB.

Set the TB to 0.020" gap at idle, then set the TPS to suit that.

There are lots of other things it could be, but that is where I'd start.

cheers
~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
monoi
Posts: 134
Joined: Mon Nov 02, 2009 10:15 pm
Location: London

Re: Engine temperature

Post by monoi »

Sorry for the lack of follow up, time flies by and the car is in my garage, away from the salty roads!

I'm sorry Brucey, but I fear I have no idea what you are saying...

TB: Throttle body and TPS: throttle position sensor?

Where is the gap you are talking about? Any tech articles I could read to get an idea?

I will confirm the thermostat thing. I would be surprised if there wasn't but then again the last people who touched it didn't leave me with a lot of confidence.
635 Csi highline 3/89
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Brucey
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Re: Engine temperature

Post by Brucey »

TB adjustment is described in the workshop manual. The clearance is set between the butterfly and the bore.

cheers
~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
monoi
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Joined: Mon Nov 02, 2009 10:15 pm
Location: London

Re: Engine temperature

Post by monoi »

I thought I'd give an update.

Finally got round to changing the thermostat with OEM, which was a lot easier than I expected. Temperature needle is now right in the middle.

I think I also found the reason of the hesitation fortuitously...the vacuum hose going to the pressure regulator, although changed recently, was barely holding onto said regulator when I wiggled it...

It's nice when things are sorted so easily.
635 Csi highline 3/89
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Theantony
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Re: Engine temperature

Post by Theantony »

I’m in the same spot. I presume you flushed your system, what coolant did you use I was thinking xtreme g 48 and how much did you need.
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