Could anyone tell me this? My own runs at around 78 C which i believe is too low and therefore effecting the mixture to not reach full 'lean' setting.

If i can establish that it needs to be a few degrees higher - say around 85 (i'm in Lebanon, so it's a hot country)- then i could begin the process of trying to fathom out how to fix it, i/e prob starting with the coolant temp sensor as my car seems to be running too rich (well, its misfiring when hot, accelerating)
Almost forgot to mention that the o2 sensor was removed yonks ago by previous owner

thanks for all your help

martin in beirut

Of course start with by checking the engine temp with an infrared heat gun OR a direct temp thermometer, then replace the thermostat if it still too low.

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Normal operating temp on most of these cars is right at 80C.

Perhaps your car is equipped with a lower temp thermostat? I think the normal/stock one opens at like 87C or something like that.

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With a 79C thermostat, your temperature makes sense.

Being in Lebanon, keep it that way. The other thermostat is 87C...which for your climate makes no sense.

Being in Arizona here, summers reach almost 120F, so 79C thermostat is imperative with A/C going in traffic. Any extra helping hand makes the difference.

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Many thanks to both of you! So, finally after reading about 30 postings which were never entirely clear, i finally have some clarity! I can now move on with the fault finding.
Much appreciated! Cheers
Martin in Beirut