Possible head gasket leak? Or something else?!

[pacman07]

Hi, I have a 1998 porsche boxster with about 123500 miles on the car. Bought it used and have had it for about 2.5 years. Previous owner had the thermostat replaced, a new catalyic converter on passenger side. i had the AOS and spark plugs replaced less than 100 miles ago. For about a hear ive noticed small coolant loss. Wouldnt happen immediately but over time depending on how long I drive. Long story short I brought it to a shop and had it pressure tested. No visible leaks at all top to bottom. However, the mechanic noticed that the passenger side exhaust manifold has white residue compared to the driver side. He suspects a head gasket leak. Wanted some opinioms on the possibility of this happening? Could it just be the exhaust manifold gasket? I do know that the car has a history of failing smog so I assume that the coolant is being burnt off/messing up the catalytic converter on the passenger side, hence why the PO replaced the catalyic converter. Ive been told that the headgaskets of these cars are very unlikly to fault but still a possibility. Thanks for all the feedback.

[JackDidley]

Originally Posted by pacman07

Hi, I have a 1998 porsche boxster with about 123500 miles on the car. Bought it used and have had it for about 2.5 years. Previous owner had the thermostat replaced, a new catalyic converter on passenger side. i had the AOS and spark plugs replaced less than 100 miles ago. For about a hear ive noticed small coolant loss. Wouldnt happen immediately but over time depending on how long I drive. Long story short I brought it to a shop and had it pressure tested. No visible leaks at all top to bottom. However, the mechanic noticed that the passenger side exhaust manifold has white residue compared to the driver side. He suspects a head gasket leak. Wanted some opinioms on the possibility of this happening? Could it just be the exhaust manifold gasket? I do know that the car has a history of failing smog so I assume that the coolant is being burnt off/messing up the catalytic converter on the passenger side, hence why the PO replaced the catalyic converter. Ive been told that the headgaskets of these cars are very unlikly to fault but still a possibility. Thanks for all the feedback.

I have an '08. I had a very slight coolant loss. The water pump was the culprit.

[pacman07]

Originally Posted by JackDidley

I have an '08. I had a very slight coolant loss. The water pump was the culprit.

Mechanic said water pump seemed decently new and fine :/ and no visible leaks

[JFP in PA]

Originally Posted by pacman07

Hi, I have a 1998 porsche boxster with about 123500 miles on the car. Bought it used and have had it for about 2.5 years. Previous owner had the thermostat replaced, a new catalyic converter on passenger side. i had the AOS and spark plugs replaced less than 100 miles ago. For about a hear ive noticed small coolant loss. Wouldnt happen immediately but over time depending on how long I drive. Long story short I brought it to a shop and had it pressure tested. No visible leaks at all top to bottom. However, the mechanic noticed that the passenger side exhaust manifold has white residue compared to the driver side. He suspects a head gasket leak. Wanted some opinioms on the possibility of this happening? Could it just be the exhaust manifold gasket? I do know that the car has a history of failing smog so I assume that the coolant is being burnt off/messing up the catalytic converter on the passenger side, hence why the PO replaced the catalyic converter. Ive been told that the headgaskets of these cars are very unlikly to fault but still a possibility. Thanks for all the feedback.

If you have a bad head gasket, it would be the very first one ever heard of. These engines use multi layer steel head gaskets that are actually stronger than the cylinder head or engine block, they never fail.

[pacman07]

Originally Posted by JFP in PA

If you have a bad head gasket, it would be the very first one ever heard of. These engines use multi layer steel head gaskets that are actually stronger than the cylinder head or engine block, they never fail.

Yeah thats what I keep reading/hearing about. Good to know! Thanks for the advice.

[stealthn]

New coolant cap