Intermittent noise, possibly valvetrain after overheating at the track
#12
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I actually work in a repair shop. So I did them myself. Very doable with the engine in the car. Just unbolt the heat shield over the rear manifold the turbo and remove the clamp holding the lower shield to it, and then just manuver it around to acess all the bolts. I soaked them in PB blaster overnight and they all easily came loose, I used a shaved down 8mm allen socket with a wobbly on a couple. Otherwise its straight forward remove intake and timing belt stuff.
#13
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Update:
Warmed up the car (same smoke), and pulled the plugs (a tiny bit of smoke wafted out of the cylinders through the spark plug hole).
1. did a compression test (dry, but fully warmed engine)
2. all cylinders between 155-175
3. something strange happened on cylinders 2 and 4
On cylinders 2 and 4, I ran the test once and it got to ~155 psi, then it slowly released pressure. I ran the test again (so that I could try to video it). This time around the cylinder pressurized with a CLICK. And held at 155-160psi.
I'm starting to doubt that the smoke is coolant … perhaps it's a red herring, some coolant that hasn't burned off. The coolant level has stayed steady in the overflow tank.
@Prospeeder/@the_duke any thoughts on the click noise, or what to debug next?
Warmed up the car (same smoke), and pulled the plugs (a tiny bit of smoke wafted out of the cylinders through the spark plug hole).
1. did a compression test (dry, but fully warmed engine)
2. all cylinders between 155-175
3. something strange happened on cylinders 2 and 4
On cylinders 2 and 4, I ran the test once and it got to ~155 psi, then it slowly released pressure. I ran the test again (so that I could try to video it). This time around the cylinder pressurized with a CLICK. And held at 155-160psi.
I'm starting to doubt that the smoke is coolant … perhaps it's a red herring, some coolant that hasn't burned off. The coolant level has stayed steady in the overflow tank.
@Prospeeder/@the_duke any thoughts on the click noise, or what to debug next?
#15
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Smoke does not stop … but I haven't run it for very long due to fear of valvetrain damage.
I can't really tell honestly. It doesn't smell absolutely disgusting, so I assumed it wasn't oil. I'll have to ask someone else with a better nose to smell it.
I can't really tell honestly. It doesn't smell absolutely disgusting, so I assumed it wasn't oil. I'll have to ask someone else with a better nose to smell it.
#16
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Coolant level has not gone down in the coolant overflow tank (I marked the level a few days ago with tape). Strangely, it has maybe gone up …
I'm guessing that the coolant level in the tank may not be a good indicator of leaking coolant (unless it was a big leak, of course).
I'm guessing that the coolant level in the tank may not be a good indicator of leaking coolant (unless it was a big leak, of course).
#17
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Back after vacation. I think I have no choice but to pull the heads.
I pulled the valve cover on the passenger side to see what I could see. I cranked the car over a few times by hand.
Nothing obviously broken. The exhaust valve springs that I could see are all intact. The cams appear fine with no visible damage.
Not sure what else I can try next without pulling the heads.
Suggestions?
I pulled the valve cover on the passenger side to see what I could see. I cranked the car over a few times by hand.
Nothing obviously broken. The exhaust valve springs that I could see are all intact. The cams appear fine with no visible damage.
Not sure what else I can try next without pulling the heads.
Suggestions?
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