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Possibly warped head but hoping just gaskets

V6 3.8L 3800

Was experiencing overheating issues and avoided operating the vehicle until I replaced the thermostat. Took it out for a drive and everything was looking good until a spike in heat after about 10 highway miles. Parked the vehicle and let the car cool off for a few hours. Tried to make the trip back home but immediately overheated so bad the car stalled out.

Had the vehicle towed and a few days later watched the vehicle at idle and no overheating but some high temps. Was getting some white smoke off the bay by the firewall at the back of the engine so chalked it up to a bad head gasket.

Removed the intake, exhaust, and both heads with no definite sign of gasket failure. Found a lot of oil in the upper intake manifold and oil in 2 of the cylinders. Need to inspect the heads for warpage but wondering if the heads may be fine and the issues could be due to intake and/or intake gasket failure?

After all this I’d take the heads to a machine shop to be checked.

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On this V6, take the intake manifold with you. The machine shop will have enough experience with these engines to know if the manifold needs machining after the heads are cut.

buy a precision straightedge and check the heads yourself. The tool doesn’t cost an arm and a leg

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So replaced all the gaskets but didn’t really check for warpage since multiple people suggested it was unlickly witb no smoke coming from the tailpipe.

Got it running and after maybe a minute the smoke on the right side started. Could this still be a sign of a warped head or possibly something else?

By now a warped head could have caused one of the new head gaskets to fail. Why not just take the heads to a machine shop and get them cleaned up?

Might just end up taking it to a shop but can a gasket fail within a minute of starting at simply at idle?

I would bet that none of those people were on this forum . Who were these people and what were their qualifications ?

Sure it could

Another car forum and didn’t check for qualifications.

Before tear down I found some oil on the right side on the upper exhaust header bolts. Made me doubt the head gaskets and possibly something above. During tear down I did find a decent amount of oil in the lower intake and some in 2 of the cylinders.

Honestly was hoping it was a non head issue and just a gasket on the way.

Any of this sound familiar?

I believe I have oil leaking and haven’t run the car past idle since I swapped out the thermostat when I was having overheating problems previously.

Previously I had left the car at idle to try and potentially track where the leak was but has been hard to tell since its on the right side. Once cooled I found oil on the header bolts which deterred me more from a head gasket or head issue.

I should have gotten the heads checked but not being a mechanic and unfamiliar with the area I wasn’t having much luck finding a shop but have a limited time frame. With what I was seeing I took the risk of hoping it was another gasket or issue along the way.

This time I only ran the car for about a minute before the smoke returning and called it a day.

I appreciate the feedback and I think now its time to just turn it over to the professionals.

Engines usually smoke for a few minutes after assembly from these repairs. How thick is the smoke? Fill the cooling system and run the engine for ten minutes.

Before and after the repair it was relatively thin and light overall and will try more tomorrow and report back.

Actually, when an engine has been severely and chronically overheated the mating surfaces of the heads, engine block deck, and intake manifold flanges should all be checked before reassembling something like this. E.G. anything over .002 inches means they need to be surfaced although the engine block deck can be problematic for obvious reasons.

Something else you should consider. Severe and chronic overheating can also seize rings in the pistons and score cylinders/cylinder walls. This can lead to oil consumption to one degree or the other. Once driven regularly you really need to keep an eye on the oil level.

Is intake plenum plastic or aluminum? Is it burning coolant?

Well let the engine idle for about 10 minutes and got a consistent amount of thin white smoke mainly from the right side but even saw some on the left side. What I feared the heads do need to be machined so going to take it to a mechanic since I don’t have the time or proper facilities to go at this again. I live in an apartment where I am not suppose to be working on vehicles and they want it running and updated tags or off the property

NEVER… as in EVER… remove one cyl head let alone 2 and not check them for “square”

The amount of warpage is not discernible by eye or feel without a machinists straight edge as you were advised to buy prior in this thread.

You should have heeded that excellent advise of Mr @db4690 or let a shop do it for you… takes a good machinist literally seconds to check this.

The vast amount of work involved all hinges upon the integrity of the squareness of those cyl heads.

Sorry to hear you skipped that critical step

And no one can say for sure whats up until that squareness is validated… mega mega critical… its the entire ball game literally.

Once square is confirmed or denied… u move on to cracks…

This is how its done… period.

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When I worked as a mechanic some 40+ years ago I worked with a guy who did a lot of engine rebuilds. He was very well respected in the area. He would NEVER rebuild an engine without milling heads and/or block smooth. Said he was burned too many times not to. Times and technology have changed, but I’ll bet some of what he said still holds true.

I understand and a huge risk I was taking but I had a limited time frame so I took it unfortunately it did not work out.