Hesitation after replacing radiator
 

Radiator in a '96 GT 4.6L took a dump on me last week. Upon inspection, I noticed one of the plastic tanks had a giant hole(more like 1/4 of the tank was missing). In my opinion, the car seemed to always run a little hot, so when shopping for a replacement, I opted upgrade from the single core to a tri-core all aluminum radiator from Champion. New radiator installed without any problems. Drove the car for a few days and everything seemed fine. Then yesterday, I fired it up, backed out of the garage, but when I tried to accelerate, it was real hesitant. Thought maybe there was just air in the system, so I let it warm up a little then burped it, which made no difference. Took if for a quick ride around the block, and it stumbles upon acceleration, regardless of rpm. Since it ran fine for a few day and without touching anything else(except for pulling and inspecting the condition of various cooling system hoses), I'm left scratching my head. I was just about to order a water pump but thought I should seek some advise first. Could the water pump possibly cause this type of stumbling, and is there a way to test it? Or is there something else I should be looking at all together? Aside from the new radiator, I don't believe there has been any upgrades to the cooling system and is pretty well stock.

the cooling system will not cause a stumble or hesitation. im more concerned with how a radiator that had 1/4 of the tank missing was only running "a little hot" with the tank being broken like that there would be no coolant to cool the engine at all. check the basics, spark plugs, air filter, fuel filter, etc for your hesitation. but the cooling system not likely

When the rad lost the chunk of the tank, I instantly lost a lot of power, pulled over, and had it towed home. Pretty much all coolant was gone at that point. When I said it always ran hot, I was implying it ran hot up until the moment the rad went. I read a lot that Ford really screwed the pooch when it came to the cooling system for '96, and had made significant changes for '97. Just replaced fuel pump and fuel filter about 3 months ago. In the process of pulling plugs, and checking wires right now. I guess it was just coincidence that the hesitation and stumbling started just after installing the new rad. Thanks for the advice.

The plugs will tell you the whole story. If you have time to check them one by one and remember which cylinder you removed them from, post the description,cylinder # or pic of each one here.

I already checked the plugs on the right bank and everything looked rather well. Will start on the left bank after grabbing some grub, and will post pics of each as requested.

Here is a picture of the plugs I pulled from 5,6,7, and 8. This is basically what I found on 1 through 4 as well. There wasn't any one in particular that stood out from the rest. Forgot to include this in the last post, and I think I may have actually resolved the issue. Whoever installed this set of plugs had them gapped at .065, across the board. I closed them all up to .050, reinstalled them, and all seems well. I also cleaned the EGR, IAC, and MAF, so I'm not quite sure what exactly solved the problem, but I think it's safe to say it was a combination. Hopefully everything is still good after running it for a few days, but for now, I think we're good. Thx