June 8, 20169 yr Hi guys... My 2002 wrx has just started to run rough more on tick over once driving seems ok.... I've had a compression test done and cylinder 1 is really low compared to the rest and the car is smoking much more... Is this a valve or piston problem and how I go about checking and fixing.. Ian
June 9, 20169 yr If it's down on compression I'd say valves or compression rings . either way it's at least a engine out and heads off job .so just in gaskets ,Machining costs and a timing belt kit you won't get much change from £500 . Unfortunately that's without any labour costs and statistically it's more likely to be rings . Which means a full rebuild and a £1.5k + price tag . If it's not broke .....upgrade it 😊
June 9, 20169 yr Author Had replacement cylinder heads on at the beginning of year and all new timing belt due to belt jumping teeth on timing so I swapped the cylinder heads over etc new belt kit etc been running ok for about 3 4 months but now I've this problem
June 9, 20169 yr Savage is pretty much spot on. He's not often wrong about those sorts. Your definitely going to be a few notes lighter in the wallet to fix it
June 9, 20169 yr Did you check the deck face of the block for trueness and the piston to deck height before putting the new heads on ? As both of those measurements need to be taken into account when calculating your new head gasket thickness ,especially if you intend to use different version heads on different version bottom ends . Any of those variations could cause a uneven compression ratio and cause the head gasket to fail but scoobs normally push combustion gasses into the coolant when the headgaskets fail (not burn oil) . So I'd check the bores for wear (especially ovality and taper) if everything "looks" ok when you whip the heads off . If it's not broke .....upgrade it 😊
June 10, 20169 yr Author Didn't check much to be honest I just managed to get a pair of heads from a rally shop who assured me they were in perfect condition etc... New belt kit new gaskets just got the thickness sizes from goole lol.... Im not a mechanic so I was surprised I got it back running all by myself to be honest....
June 10, 20169 yr Only reason I mentioned it is cos it would be nice to know why it's happened (so you can avoid it happening again) . It would be good hear it's just popped the head gasket and lost compression but they normally only burn oil when rings or turbos fail . So to have the combination of oily smoke and lack of compression means it probably rings . Best of luck and let us know what you find when stripping it down [emoji106] If it's not broke .....upgrade it 😊
June 10, 20169 yr https://www.google.co.uk/webhp?sourceid=chrome-instant&ion=1&espv=2&ie=UTF-8#q=leak down test
June 18, 20169 yr Author Hi guys... Update n advice again time.... Afterdriving car today I had bonnet open and I could hear a hissing sound coming from what seems to be down under/around the turbo area... Could this be anything to do with my compression problem?
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