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Misfire 2.4 S

M

MIB 959

New member
At 115K miles, 15 months from a major service by reputable independent, start-up is normal, at first road junction ( i.e. not warm ),
misfire on one cylinder. Fires normally when 3K rpm is reached, thereafter pulls normally. After a short stop, misfire appears again. My local autoelectrician guru excludes distributor cap crack, suggests replace all plugs and leads. Any suggestions gratefully received.
Colin Palmer
 
u just got to do it step by step and illiminate ...............even with rebuild bet u got older relays , cold start etc , plug leads/ caps possible of course then fuel system .theres no quick answer.......................just for luck one very reputable London indie , great with these cars , picked up a load of faulty fuel pipe , goes mushy and collapses , like when u suck, it closes ..................even fitted to his own Classic Lemans race car ,+ mine and 2 others last summer ............................good luck ................rolling road with Bob Watson might reveal ????
 
Does the misfire cause a bang out of the exhaust or is it backfiring into the inlet manifold? Is it at a particular RPM? what fuel are you using? the cheapest works well on this low compression engine at 8.5 : 1. Are all of the butterfly linkages correct ? none worked loose causing that cylinder to run weak or rich certainly different from the other cylinders. What spark plugs are you using? What do they look like? I have found Bosch to be the best for my 1973 2.4S engine and am currently running on Bosch Silver W5CS set at 60 microns. Is the hot air supply from the nearside heat exchanger bringing hot air to the thermostat on the fuel injection pump, if the heat exchanger is holed the air doesnot reach the thermostat and the engine runs very rich - which it does not like - it misfires. More details please.
 
I had this on my 3.2 in my 73T.
The plug lead on number 3 cylinder(?) the one in the bottom left hand corner when looking at the engine had suffered sever corrosion on the plug head where it snaps over the plug terminal itself.
I had a spare, swapped it over and it has been perfect for 10+ years.

Rain/car washing gets to that plug more readily than the others?

As above, change the simplest things one at a time.
 
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