Please Help...I'm going in circles. New engine, over heating and missfiring.

[rob4292]

Hey guy, I could really use some advice. I just had a stock 98' 4.6 gt engine installed in my 96' gt. Also had a new fueal pump installed. Well its been a couple weeks and the car the car started to over heat like almost the first day, but it over heated with the old engine. I asked the mechanic to check the water pump on the replacment engine and he said it looked fine. So I figured it was the radiator. So I installed a new radiator but it still runs warm in traffic. the needle sits on the "A" but drops down to the m almost once we get moving again.

But the next problem was the car started running bad, spitting and sputtering, would have to down shift just to accelerate anything under 2500 rpm. So I figured new plugs and bought them $10 a peice bosh plugs. Didnt fix it. So I went down to Discount auto and the hooked it up to there dianostic machine and here is what it says:
DTC 118
ENGINE COOLANT TEMP
CIRCUT HIGH INPUT

DTC P0306
CYLINDER 6
MISSFIRE DETECTED

DTC P0172
SYSTEM TOO RICH
(BANK 1)

So im going to go pick up a new set of plug wires and hopfully this will fix the missfiring, but my question is if that does fix it, would it also fix the "system to rich" error.
And any ideas what the circut high input on the engine coolant could be. I also have a new thermostat.

I appricate any help guys, I live in south florida and have been driving 100 miles a day for 3 days with it like this. Any chance the cylinder #6 plug is ruined. its one of the bosch irodium $10 plugs....im on a super tight budget....again...appricate any input.
o/2 sensor is reading to rich
number 6 cylinder is miss firing

[bullitt482]

Hmm... Could be your coolant temp sensor going out, could be the electric fans not kicking in like they should, could've hooked up the sparkplug wires wrong...... Several things. Maybe someone else will chime in with more info.

[white 98 gt]

one of the things i would do is get rid of the bosch plugs. never ran well in my car at all. autolites, motorcrafts, some here use the ngk's also. like bullitt482 said,make sure you didn't mess up the firing order. don't get the cheapy wires. at the very least get motorcraft wires. hope this stuff helps. let us know what happens...

[Herbstang]

May help Automotive Questions and Answers -


DTC P0306, the condition often can be traced to the EGR system. According to Ford, carbon can build up in the EGR ports in the lower intake manifold, . To diagnose the problem, remove the vacuum hose to the EGR valve, cap off the hose, then increase the engine speed to determine if the condition abates. If it does, inspect the EGR ports in the lower manifold for carbon deposits. If contamination is evident, clean the ports using a pick and an appropriate solvent.


Ford DTC P0171, P0172, P0174 And P0175 Description And Possible Causes

[bullitt482]

That dam EGR again.... Ditch it and get it tuned