Would white smoke be caused by intake manifold?

[Jeff J]

This is for a 4 cyl Nissan Frontier 2.4. Is it possible to get white smoke from the exhaust from an intake manifold leak on this vehicle? Would there be any difference in smoke symptoms between an intake manifold and head gasket leak?

Topic

[Nicholas Clark]

The only way I can think that an intake manifold can cause smoke of any kind and it ISN’T a coolant leak is when there is excess carbon buildup in the intake because the car is never run hard.

[Jeff J]

[quote=”Hockeyclark” post=161337]The only way I can think that an intake manifold can cause smoke of any kind and it ISN’T a coolant leak is when there is excess carbon buildup in the intake because the car is never run hard.[/quote]

I’m thinking it is a coolant leak. Is there an easy way to differentiate between and head gasket coolant leak and intake coolant leak?

[Dave Tidman]

If I recall correctly (since I have the same engine type in my 2003 Frontier), there are coolant pipes that head toward the throttle body that are prone to leaks. You might want to check those. Are you losing coolant? You could either add dye to your coolant and see where the leak is or you could do a block test (look for exhaust remains in the coolant) to determine if it is a head gasket or not. Other options are doing a leak down test to rule out the head gasket.

Since you didn’t mention a year, the general section to get the FSM for the frontier (or any Nissan) is http://www.nicoclub.com/nissan-service-manuals. You can check the cooling system section for the routing.

Good luck and keep us updated.

[Jeff J]

[quote=”dtidman” post=161341]If I recall correctly (since I have the same engine type in my 2003 Frontier), there are coolant pipes that head toward the throttle body that are prone to leaks. You might want to check those. Are you losing coolant? You could either add dye to your coolant and see where the leak is or you could do a block test (look for exhaust remains in the coolant) to determine if it is a head gasket or not. Other options are doing a leak down test to rule out the head gasket.

Since you didn’t mention a year, the general section to get the FSM for the frontier (or any Nissan) is http://www.nicoclub.com/nissan-service-manuals. You can check the cooling system section for the routing.

Good luck and keep us updated.[/quote]

Was your Frontier a V6 model? Thanks for the link.
If the oil is not discolored (milky), does this mean that it is more likely an intake leak? There is a lot of white smoke, so it may just be burning coolant direct.

It is an 02

[zero]

The only way to know for sure is to do a pressure test and try to find the leak. If it’s in the intake manifold, you should be able to hear air coming out through the throttle body with the plate propped open. If it’s a head gasket, removing the plugs will let you hear and maybe see if any coolant is getting into the cylinders.

http://www.ericthecarguy.com/faq/finding-and-fixing-leaks?start=3#FindingCoolantLeaks

[ryley]

You can use a compression tester, just keep in mind it’s a fast check tool that can be incorrect.

Here is what i do, Pull spark plugs, check all cyl. Now you can get a good compression reading and have a bad head-gasket. Second check, pull the rad cap make sure it’s full and leave it off for the test, PUT the spark plugs back and use the tester on each put each plug back.

WARNING wear safety glasses, stand off to the side of the rad. Unless you want a coolant bath. This is a back yard trick i use, the leak down is the best but you need a compressor. Sometimes I am working in the boondocks, hauling my compressor/gen-set is not the best choice.

[Accord]

Here is something easy you can do . remove rad cap then start vehicle and let worm up to normal opp temp . then watch rad coolent. If you keep getting bubbles you a blown gasket or worped head / block . another thing is to look at the bottom of rad cap . if you see somthing that resembles mud thats a clear indication that exhaust is mixing into the coolant. On a weeks times scale how wuch cool do you replace ? One cup or more to top off rad ?

[Author]

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