please help!

[carter08]

hey guys this is my first post here and am some what new to the 3800 i have a 04 gtp with 105k on it and and it as a cylinder 3 missfire took it to the dealer and thay checked my ignition and fuel system and both check out perfect thay did a compression test and all cylinders were at 180 psi and number 3 was at 140 i was originaly thinking head gasket but every one says its rare for them to go i have some oil in the rad and loosing coolant no smoke or visible leaks i did a leakdown test and had air leaking out the TB bad intake valve? bad head gasket? im really lost and dont want to put the time and money into replacing the head gaskets and it not be the problem sorry for the long post i just need help thank you

[dpzelenak]

if you had it leaking from the tb then your intake valve is bent or stuck open..maybe due to carbon bulid up?..it would be weird to have a bent valve and nothing else wrong

[carter08]

the motor was neglected by the previous owner i still have alot of power and the miss is only at low rpm like between 900 and 1500k the only way to check the valves would be to pull the head off right? and a bent valve wouldnt let oil in coolant and loss of coolant in the rad correct?

[dpzelenak]

no it wouldnt..a blown gasket or a cracked block would tho..but it would be burnin oil and smoking and also running hot if that was the case

[carter08]

Well I'm going to take the leap and tear the heads off tomorrow and inspect everything I apreciate the help and will post what I find out thank you for ur help

[2007gpgt]

If there is oil in your coolant, must be a blown head gasket.

[carter08]

Well turns out its a bent intake valve fixing that hopefully it fixes all

[blueguy]

Since it's apart...you might as well upgrade to the Metal Lower Intake gaskets as well...

[WHT98GTP]

Def upgrade the head gaskets. You should be ok. Good luck!

[carter08]

I did get the aluminum LIM gasket way nicer than stock and am putting new head gaskets since its tore down putting it all back together Thursday

[BillBoost37]

Did you find anything?

[dpzelenak]

Well turns out its a bent intake valve fixing that hopefully it fixes all

Did you find anything?

this help?

[carter08]

Well got the valve in it didn't leak put it back together with updated LIM and head gaskets
Started it up and no miss fire strong idle no leaks its good as new thanks for everyones help on here it was much apreciated