2005 Sunfire 2.2L DOHC Ecotec
Did compression check on all cylinders. All were the same.
was 210 psi after 4 puffs, and upto 230 with 6 or 7 puffs.
I'm concerned that that is too high.
I was under the assumption that these cars typically had Max PSI of 180.
Is 210-230 psi compression OK / safe?
Is it normal to be so high?
Is this an indicator that engine and head is in great shape or have a serious problem. (low compression or difference in compression are usually signs of failures)
What would cause compression to be high?
Could timing chain slipping a tooth cause this?
Could clogged exaust cause this?
Also, car has vacume problem. Measured at the intake manifold test port, the vacume is between 0 and 8 inHG, with test needle jumping back and forth between values very quickly.
typically jumping needle would indicate valve leak problems or intake gasket leaks. But haven't seen a vacume that low, while engine has such good consistent compression.
engine sounds noisy, sorta pingy like low in oil, but has OIL.
(have not checked fuel pressure yet)
Only ODBC code is P0300 multiple misfire.
Ive already replaced ignition coil, ign module, boots, spark plug.
Verified Fuel pressure of 55 psi at idle. (higher than normal for at idle, but because no vacume to fuel reg port located on tube outside of throttle body)
Fuel injectors are all operating (but didn't remove to measure flow).
note: after 1 day of operation, the new plugs have a ton of sute buildup on the ends. the old plugs, that were in for many years, had some ware but were surprisingly clean. So something changed recently.
has 130,000 miles on it.
Did compression check on all cylinders. All were the same.
was 210 psi after 4 puffs, and upto 230 with 6 or 7 puffs.
I'm concerned that that is too high.
I was under the assumption that these cars typically had Max PSI of 180.
Is 210-230 psi compression OK / safe?
Is it normal to be so high?
Is this an indicator that engine and head is in great shape or have a serious problem. (low compression or difference in compression are usually signs of failures)
What would cause compression to be high?
Could timing chain slipping a tooth cause this?
Could clogged exaust cause this?
Also, car has vacume problem. Measured at the intake manifold test port, the vacume is between 0 and 8 inHG, with test needle jumping back and forth between values very quickly.
typically jumping needle would indicate valve leak problems or intake gasket leaks. But haven't seen a vacume that low, while engine has such good consistent compression.
engine sounds noisy, sorta pingy like low in oil, but has OIL.
(have not checked fuel pressure yet)
Only ODBC code is P0300 multiple misfire.
Ive already replaced ignition coil, ign module, boots, spark plug.
Verified Fuel pressure of 55 psi at idle. (higher than normal for at idle, but because no vacume to fuel reg port located on tube outside of throttle body)
Fuel injectors are all operating (but didn't remove to measure flow).
note: after 1 day of operation, the new plugs have a ton of sute buildup on the ends. the old plugs, that were in for many years, had some ware but were surprisingly clean. So something changed recently.
has 130,000 miles on it.
