NeWyoRksPLaYaZ said:

Some of the mods include, front mount intercooler, no a/c so there is only one fan and a few others like larger turbo, jrp lifters, ebay blo off valve, hard welded piping and some others which have nothing to do with motor running cold I think. Where is the thermostat located exactly? I followed the lower radiator hose and it it at the end of the hose? Is there a writeup of it anywhere here, I tried searching and didn't come up with anything which shows a step by step way

Click to expand...

Follow the upper radiator hose. The thermostat housing is at the end of the hose, bolted to the block. On my 420A it was 13mm, 4G63 could be different.

Pull your thermostat out, if you can see through the middle of it it is stuck open. Your symptoms (running cooler once moving at speed) sound exactly like when my thermostat stuck open. I could be at full operating temperature and do a pull, and my gauge would go down to about a quarter.

It wont really do any damage running like that, but your gas mileage can suffer.

If you replace it, heat a pot of water on the stove to the temperature your thermostat is supposed to open at (use a thermometer to keep an eye on temp, i use whats called a candy thermometer which you can buy for less then $5) and then set the new thermostat into it. If it doesn't open it is bad. I've gotten bad thermostats right out of the box before, so now i check the new ones before i replace the thermostat in anything. My record for bad ones in a row is 6. .

clipto said:

Ask yourself this...When was the last time you did maintenance? No but check coolant system and can get a cxracing aluminum radiator on ebay cheap if you want keep low temps.Front mount's do block radiator but never really seen issue with them causing that much blockage.If you wanna go nuts can rip out the a/c condesor inbetween the front mount and the radiator if you don't use a/c. Natural for moving air to cool stuff down so makes sence while driving air cools stuff.But thats really the simplicity for cooling temps.

Click to expand...

The OP's problem is his temps are too cool, and he wants to stabilize them.

^its actually on the lower hose, its held on by 2 12mm bolts, i bought the thermostat from pep boys and the gasket from autozone. I went for a decently long drive on a open highway and temps stayed where it should, the half way mark so this is one less issue down i want to thank every one for all the help i really appreciate it. Just so if anyone is having these same symptoms, change the thermostat

The only thing I would be worried about is it getting cold enough on the highway to go back into open loop. This would cause it to go back to a rich condition to try to warm up the engine. You dont really want to be cruising for a long period of time in open loop and doing so will cause poor fuel economy!

The OP's problem is his temps are too cool, and he wants to stabilize them.[/QUOTE]

Haha i feel like a newb.

NeWyoRksPLaYaZ said:

^its actually on the lower hose, its held on by 2 12mm bolts, i bought the thermostat from pep boys and the gasket from autozone. I went for a decently long drive on a open highway and temps stayed where it should, the half way mark so this is one less issue down i want to thank every one for all the help i really appreciate it. Just so if anyone is having these same symptoms, change the thermostat

Click to expand...

Apples and oranges apparently . Didn't know it was on the lower hose on the 4G. Glad you got the issue handled though.

Why you need the 'stat is for two things: Keep the coolant flow under control so the coolant can pull the heat from the block and to keep temps are a certain level that the ECU is programmed for to keep the system in a closed loop condition for best motor effiency.

Remove the 'stat, or a stuck open 'stat and the opposite conditions will be results from what is listed above.

Moving air flowing over a heat exchanger lets it do its job properly. More at 11, stay tuned!

.
.
.

But seriously, if you are that worried about the T-stat, pop the 3 bolts on the housing and check her out.

Your Thermostat control's what temperature you engine keeps, if it keeps a lower temperature while on the vs. city driving it means open.

Go with a stock o.e.m. thermostat and it should be fine.

A thermostat is designed to keep a engine at a *certain* temperature.

Has no one noticed the OP solved his problem nearly a month ago?