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p0304 code and engine overheating!!!!!!!

sinister1

New member
:th_shakinghead2:Ok guys here is my question I have a 2001 gtp with 93,000 miles on her. I have changed the plugs, wires and the #4 injector switched coils to try and nail down what is causing this code? Not to mention the over heating issue i have flushed the radiator and changed the thermostat. i have inspected the vaccum lines as well can't find a problem there. So what am i missing? oh yeah plus the fuel filter has been changed. im running a K&N air filter and autolite 606 plugs. with autolite 7mm plug wires. Any help would be great.
 


I'm not loosing coolant that im aware of . Fans are starting in low speed then stepping up to high. I havent seen any bubbles except in the coolant res. Its over heating but never making it into the red the fans kick on around 210. It does however rise above that even when driving unless you are running around 70 then stays well below 210.
 
Have you Burped the system after your coolant flush? Air bubble maybe stuck behind thermostat... check around vibration dampner for moisture/coolant , i have the same car in the garage and also found usage of very small amount of coolant (not enough to worry about) over a weeks time.. but will overheat when idling
i found the alternator bracket is also a coolant housing for the heater core hoses.. this housing plugs into the block(center of motor,a plastic 90*tube under blower pulley) and into housing that water pump is attached to. it may look like this--
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on the thermostat housing there is a brass screw, warm up the engine and open the screw a few turns, when bubbles stop coming out and you get a steady stream of coolant shut the screw. top of the radiator.
 


you should really leave the rad open and just run the car till the fans turn on then top up the rad and that should have the air all out of it. as for the missfire..... have you checked the connector for the injector? if the pins are not making good contact it will cause a missfire condition. I had this on cyl #3 when I first got my car, took a bit to find it but finally found that the ground terminal was just not making a good connection. used a small pick and bent the tabs back down so they would press tighter on the pins of the injector and BAMM! problem solved!
 
actually you are only supposed to open the screw while filling not while running the car and the air will make its way out of the open rad just fine. look at the system the top of the rad is higher than the brass screw so........ Guess where the air will go!!! you got it champ to the top of the rad where there is the.......... Open rad cap!
 


Alright you obviously know best! I will reconsider my current profession as an automotive technician :th_eyesrolling:
 


Pull the plug on #4 and see if any coolant is on it or and goopy stuff at all. When my car had a overheating problem it was my lower intake gasket and by overheating it my back head cracked lol it sucked so dont let it overheat shut it down if it goes too far past 210, and keep checking your coolant levels
 
I don't see any reason to be butthurt. Even after filling the radiator to the top, the coolant hose has a couple of bends in it that you've got to work at to get air out.
As long as the end result is achieved, who cares?
 
If you keep fighting... I've had a couple stubborn ones in the past. Try putting it on ramps to elevate the front and pull the rad cap to try and help air move around.

If that doesn't do the trick, pull the T stat and ensure you fill the LIM up to the T stat, then put the stat back in and finish the rest of your burping procedure.

Most of the time I don't bother with the bleeder screw. 90% are fine without it.. it's the 10% that it's there for. You seem to be in the 10% from the sound of it.
 
I've always massaged the upper hose to push most of the air out while I fill it...then a quick turn of the bleeder usually helps top it off.

Whatever works.
 
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