Bypassing the throttle body coolant lines?

Shakerhood beat me to it. F-Body cars (Camaro/Firebird) equipped with TPI motors have the exact same thing, a coolant inlet/outlet going through the throttle body, and it's listed as a "throttle body pre-heater," which simply, as stated above, serves to prevent the throttle body from freezing up in severe cold conditions.

Here, where it hardly even dips down lower than 32* at the absolute worst, it's pretty pointless. I've completely removed the heater tube and its related throttle body coolant lines, and the Smog Nazis didn't even so much as blink at it.

I don't think it matters. Why would Ford produce the Cobra which doesn't use the line to the throttle body? I think if it was an important part of the operation they would have found a way to integrate it to the Cobra's intake.

simple science...

When I capped off mine, I noticed a definate drop in the temprature of the upper intake manifold by touch.

If you pull your TB and EGR spacer, you'll notice that there is quite some metal between where the gasses flows, and the coolant. I think it is there to prevent a hotspot on the intake, but not actually effective very much as to cooling the EGR gasses. If it really did an effective job cooling the EGR gasses, they would clogg up with carbon a lot. The hot gasses filled with elements when suddenly cooled, the materials would build up. This is a comon issue with many EGR systems, causing P0420 series codes, EGR Insuffiecient Flow. (OBDII reference)

The EGR should only be open durring coasting and very mild cruising. The amout of exaust gasses released is not very much. Even wih the EGR fully opene it would only maby heat the intake air by 10* or so, and durring WOT not at all because the EGR is closed. Gasses transfering tempratures to solids is much less than that of coolants transfering tempratures to solids. So would the increased air temprature heat the intake more than the coolant? The only way to tell would be to monitor the IAT sensor signal before and after doing this, and/or use a temprature sensing device to measure the temprature on the inside of the intake.

I have to agree that if your going to remove the EGR and cooling lines, do it right, pull the lower intake and use either a Felpro 1250 or 1262 and use the blockers that come with the gaskets or use something to block the flow to the intake. It is the hole in the middle between the two intake bolt holes.

Shakerhood said:

I seen this on an Automotive TV show last night on the DIY Network and they said those lines are to keep the throttle Body warm as the throttle blade will ice up.

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Darkwriter77 said:

Shakerhood beat me to it. F-Body cars (Camaro/Firebird) equipped with TPI motors have the exact same thing, a coolant inlet/outlet going through the throttle body, and it's listed as a "throttle body pre-heater," which simply, as stated above, serves to prevent the throttle body from freezing up in severe cold conditions.

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For GM TPI systems that's correct, they are connected to the TB, for Ford's EGR system, is not. The coolant lines are not connected to the TB but, to the EGR spacer and, are for cooling purposes of the EGR spacer. Why would you need to heat something that is getting hot due to the presence of exhaust gases? Don't buy it?

Check:

EEC-IV Tech Art. By John Hunkins said:

A valve on the side of the EGR spacer opens and closes to control the flow of exhaust into the intake. As the exhaust gas can add much heat to the intake manifold and incoming air, it is plumbed for engine coolant circulation. (A line on the front of the spacer feeds coolant to the spacer and a line on the back takes coolant away.)

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found in this very good EEC-IV Tech Article or check Al Kirschenbaum's 5.0 Reference book on the SEFI EGR section. This one BTW, has a 5.0 with both ports capped on its cover photos, talk about irony. GL

Unless you block off the egr passage, don't do this. The coolant is to cool your egr spacer. Not to warm it, to keep it from freezing, wtf? If you do this with hot exhaust gasses still passing through it, it will get extremely hot and eventually cook your gaskets. (don't ask me how I know this, just chalk it up to "live and learn"). The coolant passing through, is far cooler than the gases being circulated. I actually believe bypassing the lines would hurt performance. Although this is probably so minimal as to not even be measurable.