HELP!! wtf is up with my compression

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Fergus
Posts: 374
Joined: Sun Apr 03, 2005 3:09 pm
Car: '01 C5 Coupe

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Well, did my compression test today, 3 times. First 2 cylinders both showed 125 each of the 3 test. figured has to do with my 9:1 compression pistons. Nope.

Moved on to the 3rd and 4th cylinders. Bothe showed a strong 160.

WTH. I dont know what could be causing this. espically both being off the same ammount.The engine has 326 miles on since my rebuild.

Side note, when I was warming up the engine, very white smoke came from the exhaust. No blue tint showing it was oil, and didnt smell like anything but air. Also a bit of gas residue on the 1st and second plugs when I took them out.

Thanks in advance, I'll be watching for replies/


dvd
Posts: 575
Joined: Sun Jul 06, 2003 4:21 pm

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i heard white smoke = headgakset

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AmoebAssassin
Posts: 2424
Joined: Wed Nov 17, 2004 7:11 am
Car: 1991 Base fastback 5spd, black

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While white smoke is a telltale sign of water in the combustion chamber, i seriously doubt that he blew a h/g in 326 miles. Rather, its more likely that there was an error in the re-assembly of the engine. Were all headstuds and nuts properly torqued to spec, and were the mating surfaces clean when the head and block were joined? Plugs that are wet with gas are usually accompanied by black smoke or gassy smell out the exhaust, which you apparently have none of. Are you sure they are wet with gas, and not potentially something else like water or trace oil? Does the car start hard or overheat, do you lose coolant, or are there any other quirks?

Fergus
Posts: 374
Joined: Sun Apr 03, 2005 3:09 pm
Car: '01 C5 Coupe

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car tends to run a bit hot. also miss fires despit timing being correct. It is probably just water in the first two pistions. Just smells a bit like gas, but not to strong. When I was doing the compression test, there was a fine mist comming out of #1 and 2 and a bit of condensation on the sparkplug access walls.

It would be hard for the headgasket to blow. Its a thicker cosmetic metal one.

Error in re-assembly would be my first guess now that you mention it. The engine was 3 weeks late and I was pressuring him to get it done.

Would another shop be able to determine if the assembly was done incorrectly? atleast enough to where I can get someone to do a rebuild at his expense?

chmercer
Posts: 2810
Joined: Sun Mar 09, 2003 5:04 pm

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is it possible that the intake manifold gasket was put on backwards? it will go over the studs both ways, but one way, it wont seal the coolant passage. i did this one time (shut up leave me alone ), the car would run but was making white smoke due to coolant getting into the 1st cyl.

Fergus
Posts: 374
Joined: Sun Apr 03, 2005 3:09 pm
Car: '01 C5 Coupe

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not that i know of. none of the problems really started untill the other day. put a good 275 miles before I started having any problems.

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AmoebAssassin
Posts: 2424
Joined: Wed Nov 17, 2004 7:11 am
Car: 1991 Base fastback 5spd, black

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The mist was coming out of where on cylinders 1 and 2? From the spark plug area? You may want to get another shop to look at the motor and how the head attaches to the block. Best case scenario, your head nuts may need to be re-torqued. Worst case scenario, looks studs or nuts have warped your head and it needs to be resurfaced. Your timing isnt the problem, if your valve overlap was jacked then you'd lose compression across all four cylinders. The white smoke and overheating are leading me to believe you've got headgasket issues, whether it be assembly problems, warpage, or incorrect install.

Hoever if the mist did come out of the spark plug area, take out your plugs, wipe all the condensation out of the spark plug areas, and re-torque them in the head. If this continues *from the spark plugs* someone probably cross-threaded the plugs into those cylinders and damaged teh threads, allowing leakage. Do the plugs feel harder to thread in, or do they thread in funny or take an abnormally long time to seat?

Fergus
Posts: 374
Joined: Sun Apr 03, 2005 3:09 pm
Car: '01 C5 Coupe

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the mist was comming out when I did the compression test. the plugs were not in.

Talked to Fiznat (thanks) today, and he said it was either bad head install or bad decking of the block. either way its the shops fault. Just gotta figure out what Im gonna do w/o a car untill this gets fixed.


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