Spyder328
New Member
So my 2004 GT (4.6 v8, 5 speed manual) is sending some misfire codes (P0300, P0304, P0306) but I don't feel any misses anywhere. I changed the fuel filter (used a Motorcraft), changed the plugs (motorcraft), and coils. Also bought some MAF cleaner and cleaned the MAF sensor and ran a full tank of gas thru it that had injector cleaner added to it. I put about 70 miles on it (after disconnecting the battery) then the check engine light came on
I got the codes read and I had P0300, P0304, and P0306. Before I did the filter, plugs, coils, injector cleaner, and MAF sensor cleaner I had codes P0300, P0302, P0304, P0306, P0307, P0308. I drove it twice after the light came on then, where as this time I went right to get it read. I'm wondering if more codes would have shown up if I had driven it a little longer like last time. It still has a slight pop every now and then on idle and it feels like a slight stumble. I can run it on 5th gear at 40mph and its smooth and it pulls strong. All the plugs that came out looked like it is running lean. I don't have a scanner or anything to check what the fuel pressure is reading. I'm starting to wonder if there is a tune in it that I don't know of and it is causing issues. I have high flow cats, x pipe, slp loudmouth resonators, 2.5" exhaust, intake, aftermarket clutch, and under drive pulleys. I'm unaware of anything else that has been done to it as this was a recent purchase. Also worth mentioning, the hole on my intake for the air temp sensor is plugged and I can't find the wires for the sensor anywhere, I also notice I have pink injectors. I have read that the GTs came with pink or orange injectors and I am curious to why some apparently have pink and some have orange. Thanks