The engine runs fast, won't idle down, and many times the exhaust manifolds will glow red hot from the lean mixture.
To fix a head gasket on a 1984 Pontiac Fiero, start by disconnecting the battery and draining the engine coolant. Remove the necessary components, such as the intake manifold and cylinder head, to access the head gasket. Clean the mating surfaces thoroughly, then place the new gasket in position and reassemble the engine, ensuring all bolts are torqued to the manufacturer’s specifications. Finally, refill the coolant, reconnect the battery, and run the engine to check for leaks.
Yes. Antifreeze is actually pumped through the intake manifold. If the gasket is bad it is possible that it leaks out
Most often that indicates the presence of water or coolant in the combustion chambers. Common causes are head gasket leaks, intake gasket leaks, warped head/s or warped intake.
Intake manifold gasket
Some possibilities: Intake leak, head gasket leak, rad, waterpump, hoses, heatercore, cooling fans not coming on, stuck thermostat. If it's a 3.4L they are common for intake & head gasket leaks. Check for coolant in the oil (oil looks like a chocolate milkshake), look for leaks around the intake area or drips on the ground. Maybe use a gas analyzer or emmision machine to check for hydrocarbons in the rad to see if the head gasket is leaking. 3.8L are more common for intake leaks than head gasket leaks but check it over the same as above.
Might I suggest that either the leak was/is not at the timing cover gasket, or maybe something went wrong on the gasket install?
Seldom, if ever, do i see a bad intake. On the older aluminum V-8 intakes in the oldsmobile engines they used a steel intake gasket and the steel would corrode pits into the sealing surface which caused antifreeze leaks. Most of the troubles that i see with intakes are with the intake gaskets going bad or with vacumn leaks caused by split vacumn hoses or a leaking intake gasket.
If the intake manifold gasket has failed then it can cause many issues. Air leaks, known as vacuum leaks, will cause an erratic idle, stalling, and fuel problems.
To replace the intake manifold gasket on a 1999 Pontiac Bonneville with a 3800 engine, first disconnect the battery and remove any components obstructing access to the intake manifold, such as the air intake and throttle body. Drain the coolant and detach the intake manifold by loosening the bolts in a specific sequence to avoid warping. Clean the mating surfaces thoroughly, then install the new gasket and reassemble the manifold, ensuring all bolts are torqued to the manufacturer's specifications. Finally, refill the coolant, reconnect the battery, and start the engine to check for leaks.
You've got either a leaking intake gasket or a leaking head gasket. It's a serious problem which needs to be repaired.
Should just be the gasket but check the upper side of the cylinder head while you have it apart to see if it has problems. Intake gasket leaks will present vacuum problems, if pressure is pushing air out of the affected area then it may be the head.
I'll assume Lower Intake Gasket, since they tend to cause vacuum leaks. Get a manual from Autozone and expect about 4 hrs labor, you need to take off the upper intake manifold just to replace the Lower Intake Gasket. Probably should change/clean the PCV valve while ur in there. Good luck, man.