corsa b 1.4 8v 97 - running very rough and missing

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Sun 27 Feb 2011 22:51
corsa b 1.4 8v 97 - running very rough and missing - brancher

hi can anybody help please.

my 1.4 corsa is running very rough almost like hunting on tick over and at low revs missing, the head gasket had been replaced just before i bought it with the head skimmed new valves and new hydraulic lifters, iv replaced the plugs for new, fitted a known good coil pack and leads, removed and cleaned the egr valve, but no difference, can anybody help please ?

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Mon 28 Feb 2011 11:05
corsa b 1.4 8v 97 - running very rough and missing - brancher

today i tested compression on all 4 and 3 were fine 12 bar and i think no4 the closest the coil pack had 6 bar so i take it thats the problem, what should i look for now ?

help please

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Mon 28 Feb 2011 22:01
corsa b 1.4 8v 97 - running very rough and missing - Big John

You need to check if the loss of compression is valves or bores. Do another compression check on the poor cylinder but squirt some engine oil in the plug hole beforehand. If the result has dramatically improved (it will always slightly improve) then the bores/pistons/rings are to blame if not then it is probably valves. The oil "temporarily" forms a piston/bore seal. (Sorry it will smoke a bit afterwards)

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Fri 1 Apr 2011 23:12
corsa b 1.4 8v 97 - running very rough and missing - JayF Engineering Services

if it was re built before you got it and has had the valves replaced it had probably dropped the cam belt and mashed the valves,when this happens it can damage the piston crown and cause the rings to be pinched in their groove ,this destroys the compression......bottom end and head off dude ! i bet when you take the head off there is damage to the piston and the combustion chamber

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Wed 11 May 2011 04:36
corsa b 1.4 8v 97 - running very rough and missing - brancher

hi thanks for your replies, after testing compression and found 1 cyclinder had very low i got a replacement bottom end which was tested for compression before removed from other car put it in mine compression now is good on all but still no difference still missing. Since then i change the maf sensor, water temp sensor, plugs, ht leads, replacement throttle body complete with icv and injector, and know i have no idea what do try next. any help now would be great .

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