Poor running m20

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brian_s
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Fri Mar 14, 2025 4:43 pm

Put my car down to the local garage for a quick pre mot after sitting for the best part of 15 years, it’s a 1990 320 with a m20 2.5 in.

Thankfully it doesn’t need much, bar the emissions!

The reading were co : 0.13 and hc : 1200!


Any gurus out there any clues what to check first?
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BenHar
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Fri Mar 14, 2025 6:32 pm

Intake air leaks.

Ben
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brian_s
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Fri Mar 14, 2025 7:20 pm

Thanks,

have been doing some googling and found the tps wasn’t clicking so have whipped the throttle body off and adjusted it so it clicks have checked the continuity too which seems to be fine.

As far as leaks go the only loose fitting I could find was the two elbows for the brake servo to throttle body, will epoxy them in.
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