i have a 91 mkiii turbo. the problem i have is, if i keep the rpm's above idle, 2-3000 rpm. the car will misfire... pops through exhaust. it runs fine at idle and i notice the upper radiator hose is very hard when at operating temp. i have milled the head and replaced the headgasket with hks 1.2mm and arp bolts. i have checked all the ic hoses and vacuum hoses. i have checked for codes, had a code 31, replaced maf sensor with new one. problem still exists. it seems like a bhg, due to the fact that upper radiator hose is hard as can be. i also replaced the thermostat during head gasket replacement. i am at my wits end... please help!!!
Help!!!!
- Thread starter suprared89
- Start date
Are you losing coolant out of the overflow? Have you run a block test to check for exhaust gasses in the coolant?
no coolant from overflow. and i have not done the block test. i will have to do that and see what happens. would a warped block cause misfire/popping at 2-3000 rpm while standing still?GrimJack said:
Its pretty difficult to warp the cast iron block. Was that a metal gasket?
Yes....then did you have the block shaved to a very good finish??? The head AND block surfaces need to be extra fine for metal gasket.
The misfire could be a # of other things. A spark plug wire may be good enough at idle, but break down at higher rpms. Injectors too. EGR does not open at idle, but may be opening too much at the higher R's.
Low Fuel pressure, due to a weak pump, or ESPECIALLY a plugged fuel filter will definately give symptoms like yours.
If you are not blowing coolant into the bottle, I doubt the gasket is your problem. Besides, most of the 7m gaskets blow combustion gasses into the coolant, and not really let coolant back into the cylinders. If coolant went to a cyl. and caused misfires, you'd DEFINATELY smell it out the exhaust.
Hey...get busy and check those other things out.:biglaugh:
Yes....then did you have the block shaved to a very good finish??? The head AND block surfaces need to be extra fine for metal gasket.
The misfire could be a # of other things. A spark plug wire may be good enough at idle, but break down at higher rpms. Injectors too. EGR does not open at idle, but may be opening too much at the higher R's.
Low Fuel pressure, due to a weak pump, or ESPECIALLY a plugged fuel filter will definately give symptoms like yours.
If you are not blowing coolant into the bottle, I doubt the gasket is your problem. Besides, most of the 7m gaskets blow combustion gasses into the coolant, and not really let coolant back into the cylinders. If coolant went to a cyl. and caused misfires, you'd DEFINATELY smell it out the exhaust.
Hey...get busy and check those other things out.:biglaugh:
mrnickleye said:
thanks, i sure will. if i may ask one more question.... what about the hard radiator hose?? it makes it seem like the thermostat is stuck, but temp gauge never gets beyond half way??? as you can see by the time of this post... it's keeping me up way past my bed time.
Unless your rad cap is gone, your pretty much safe unless you are pushing liquid out the overflow.