caprice having some issues

[2dooreighty5]

Hello all...my 85 caprice is having some issues right now...when i start the car in the morning it back fires while it warms up...not enough to kill the idle ....but does it on like every other stroke...Im wondering if this is an ignition issue or carberator thing...also another issue im having is when crusing around town with the car fully warmed up and the the car ideling at its lowest rpm theres a tinging noise...sounds almost like the car will die or like maybe the car is struggeling for fuel...but it does feel like its gonna die...honestly sounds like a bolt just pinging around but i know its not something stupid like that...any ideas boys?

[silicon212]

By backfiring when it warms up, do you mean while it's in 'curb idle' (fast idle) or when it's under power?

That actually points to a possible failing cam lobe or two.

[j cAT]

Originally Posted by 2dooreighty5

Hello all...my 85 caprice is having some issues right now...when i start the car in the morning it back fires while it warms up...not enough to kill the idle ....but does it on like every other stroke...Im wondering if this is an ignition issue or carberator thing...also another issue im having is when crusing around town with the car fully warmed up and the the car ideling at its lowest rpm theres a tinging noise...sounds almost like the car will die or like maybe the car is struggeling for fuel...but it does feel like its gonna die...honestly sounds like a bolt just pinging around but i know its not something stupid like that...any ideas boys?

remove the air cleaner and on cold start see if its backfiring thru the carb or exhaust..could be the choke is dirty or the vacuum controlled diaphrams are not working/leak...check the vacuum lines..did you ever check the heat riser out for proper operation. its on the exhaust exit port to the muffler pipe..

if this checks out good then check the plugs, plug wires for proper resistance..

the fuel filters on these vehicles mounted in the carb should be replaced every year ...this is because of your steel tank and alcohol fuel causes great amounts of rust to plug it up...one way to reduce this is add 2 oz of the marvel mystery oil to gas , when filling her up...

[2dooreighty5]

man thats sweet you guys get back to me so quick!
Anyway yea so the back firing is only on a cold start...once the cars warmed up it doesnt do it...and once its warmed up and drops down rpm...from the cold idle to fully warmed and ready for cruising it stops....the clinking noise happens pretty much all the time...i would like to post a video on here but dont know how...should i pload to photobucket or something...that would make it easier for you guys to help me...Im gonna check spark plugs but they are all new and so are wires...to me it sounds like fuel filter..even tho its not that old...or maybethe choke...but i did take off the carb and fully rebuild and clean it within the year so i dont know...lemme know what i can do ...

[j cAT]

Originally Posted by 2dooreighty5

man thats sweet you guys get back to me so quick!
Anyway yea so the back firing is only on a cold start...once the cars warmed up it doesnt do it...and once its warmed up and drops down rpm...from the cold idle to fully warmed and ready for cruising it stops....the clinking noise happens pretty much all the time...i would like to post a video on here but dont know how...should i pload to photobucket or something...that would make it easier for you guys to help me...Im gonna check spark plugs but they are all new and so are wires...to me it sounds like fuel filter..even tho its not that old...or maybethe choke...but i did take off the carb and fully rebuild and clean it within the year so i dont know...lemme know what i can do ...

the noise may be that exhaust manifold heat riser valve...

[2dooreighty5]

i have aftermarket headers and exausht

[j cAT]

Originally Posted by 2dooreighty5

i have aftermarket headers and exausht

so the exhaust valve is gone....

headers will damage the plug wires...is this all properly insulated to protect the plug wires ? heat will damage the wires causing the resistance to increase over time
...

[2dooreighty5]

Im not sure what the exausht valve is...but the plug wires are fine...
im gonna get a video up today...