93 HCI GT has a part throttle miss and high water temp - Please help!

[blackedout93gt]

Hey guys, have 2 issues I'm hoping y'all can shed some light on.

Issue 1.

Drove the car on a 2 hr trip down the interstate today and it ran pretty dang hot (around 230-240* per my autometer gauge). The car has a champion aluminum radiator, electric fan, stock thermostat and waterpump. Granted I was driving 80 mph on the I75 but I still think this seems a little high. It stays around 200-210* driving around town. I'm going to replace the thermostat with a 180*. I just wanted to know y'alls take on this and what else I could do to lower it.

Issue 2.

Today we noticed my FMS plug wires seemed to be jumping spark. I figured this would be a perfect time to change my plugs, cap, and rotor. The car has a MSD 6AL and Coil. The car had ASGF32C Motorcraft plugs, Motorsport Wires, Stock Cap and Rotor. I went to the parts store and got Autolite Premium Wires, NGK TR5, and an Accel Cap and Rotor. The parts store computer listed the TR5 as a replacement for the ASGF32C. We got back and installed everything on the car but now it has a part throttle miss. It is fine at idle and WOT. Driving under 2K it bucks really bad and you can feel it still up to 4K unless accelerating hard. I bypassed my 6AL and the miss is pretty much gone.

Update: Well guys I replaced the plugs with some ASGF32C's like the ones that were in it and it isn't as bad but it still has a miss with the MSD hooked up. I bypass the MSD and it runs better. Do y'all think it could have something to do with these autolite wires? I need to just order some new FRPP wires and put them on.

Also, the base timing is set at 10* with the spout in and the tune is commanding 30* total. So I don't think too much timing is the culprit here. It is a weird miss though. It isn't detonating but it almost like a popping sound like when you downshift to slow down.

 

[2000xp8]

You say pretty much gone, about the miss.
Is it gone or not? Not trying to be rude, it's just a vague statement.

Always use a ford cap and rotor and ford wires, nothing works like real ford parts.

The msd being the problem would not surprise me, seems as of late they make junk.

How many rows is the radiator?

I know these guys are going to ask you if the deflector is still on the car under the radiator support, but honestly i feel like that's a myth, i rarely if ever see anyone come back here saying that was the real issue. I haven't had one on the car in 15 years (at least)

Alot of times highway cooling issues are lack of capacity.
That's why i ask how many rows.

 

[blackedout93gt]

With the MSD bypassed it is gone but with the MSD hooked up it's not as bad as it was with the TR5 plugs but it's still has the miss (it sounds like the car is burping almost). The car wasn't doing this before I replaced the Cap, Rotor, Plugs, and Wires so I'm thinking it has to be one of them.

Now for the radiator. It's a champion aluminum radiator. I don't know about the rows. I'm assuming it is a 3 row. The fan the car has looks like the flex-a-lite kit.

Thanks for your help and any other help is appreciated.

 

[HISSIN50]

Did you mean that your timing is at 10* SPOUT out? If not, that could cause some issues.

I'd try putting your old cap and rotor on and see if that fixes it. If not, put your old wires on and it should be running well again, right (we will assume plugs are ok since you went through 2 sets and are back to new replacements of what you had before).

The air deflector does matter for those in hot climates (i.e., the desert SW where it's triple digits all summer long). Folks in milder climates often don't notice a difference if it's there or not.

Good luck.

 

[seedeezy]

Make sure your radiator is topped off if you haven't already. Its very rare for a car to get hot on the highway, because it has almost and infinate supply of cool air. Either your low on fluid or your pump aint doing its thing anymore but if that was the case you would see it get hot in the city as well... and if your thermastat was an issue it would definately make the car hot in city driving as well. Haven't seen many break closed but you never know.

As far as your car missing I would put all the stuff back to how it was when it wasnt missing. Then do one thing at a time till you devolop a miss again and then you can isolate that. Or something else is actually starting to go out right when you decided to do the tune up. This would fall under the catagory that you fix one thing and something else breaks...

 

[blackedout93gt]

The car was set at 10* timing with the spout out then put the spout back in and the computer controls the timing.

I wish I still had the old cap, rotor, and plugs. I left them at my buddies shop where we dyno'd the car and it's over 2 hrs away. I ordered some FRPP 9MM plug wires and I'm going to go to the parts house and get a stock cap and rotor.

I topped off the radiator and it was pretty close to being full. It did have antifreeze in it. I'm wondering if I should drain it and just fill it with water. I know I have heard some people say it will run cooler with water.

I do live in Middle Ga where the heat is 90-100* everyday during the summer.

 

[blackedout93gt]

I think my problems are solved.

Put FRPP 9MM wires, MSD cap and rotor, and regapped the plugs and it's running fine.

Also, topped off the radiator and installed a new radiator cap. I drove it on the interstate yesterday with a heat index of 110* and it never got above 225-230.

 

[Mustang5L5]

225-230 is still pretty hot. Mine on the warmest of days never goes past 195 degrees. That temp would be dangerous for aluminum heads.

 

[2000xp8]

Ya i agree at those temps i'd probably be worried.

I still think it's a cooling capacity issue.

Filling it with water will make it run cooler when it's cold out, but hotter when it's really hot out. At those temps you are running you can almost be sure the water boils out.

You say you assume it's a 3 row, just so you know, 3 rows is pretty thick so you should be able to see the difference, the original is only like an inch or so thick, so the 3 should look stuffed in there.

I'd rule out the water pump, most of the time they either work, or don't work and leak, not too much inbetween.
If the thermostat is stock original almost for sure it's time for a new one.

 

[blackedout93gt]

Riding around town and stuff it never gets over 195*. What things would you guys recommend to try? I would say the radiator is 2" thick. Here's a pic where you can kinda see it.

 

[Mustang5L5]

So it gets hot on the highway?

Do younhave underdrive pulleys?

Also, is the lower radiator deflector still in place ir has it been ripped off?