running too cool

My prob is the opposite of most others I see on here.
I am actually running too cool.
My gauges are 40-90-120 (Canadian) and very rarely do I get anywhere near 90 (210? I would presume for US)

I just replaced some plugs that were too cool for my rig, but they are only a month old, and I had this problem with older plugs aswell.

So I have 97 w/K&N FIPK, 99+ intake & injectors, Banks header, custom downpipe, stock cat, flowmaster 50 and 2.5" to tail. Also a custom set of battery cables, very large. Thats all I can think of that would affect performance. Synthetic oil, regular changes.

Now this all started when I took the A/C condensor out from the front of the rad. removed it all together allowing much more air to get to rad, and I guess this is causing the low temps.

Highway driving I am lucky to get 2/3's of way to 90... 75 I guess maybe 80 on really hot day. With cold weather rolling in up here I don't see things getting any better. Normally I wouldn't think this is a bad thing, but I don't want to burn all my fuel in the warm up stage everytime I drive. Also trying to get some heat in the cab took as long as the 15 minute drive to work... and that was still well above freezing.

I would think my solutions would be to maybe block of some of the rad to allow less airflow past it, hopefully reducing the rads effectiveness and raising my temps back to normal.

thanks for any other thoughts tho.

I'm gonna guess that your thermostat may be stuck open.

brand new t-stat. replaced one that shit the bed.
I can sometimes get into the 90 (210) range but only in traffic on hot day, or slow moving in 4x4 on trails.

on that tho, how would I check to see if it WAS stuck open?

The t-stat you put in might not be any good. They have been known to stick right out of the box.

I understand that
I just remembered I can pull the t-stat, put in water and see if it opens, other than that is there another way to find out if it works or not?
If not its something to do this weekend.
Oh and as I said before, this really just started running really cool when I removed the condensor, allowing more air to pass thru rad... so should I still put attention to t-stat or look elsewhere too?

start the Jep cold.
get out, put your hand on the upper radiator hose.
It should not get warm gradually, it should be cold right up until the t-stat opens, then it should ge very hot, very quickly.
If it warms gradually then coolant is flowing freely when the motor is cold.

I had the same problem on my 92. I ended up replacing the temp. sensor at the back of the head. Gauge works right now. Do the 97+ have 1 or 2 temp. sensors? JIM.

IT sounds like a stuck t-stat but check the sensor first. Take it for a ride when you get back check the temp in the radiatior. If it is the same as the dash reading then it is a stuck t-stat. :doh:

this maybe a real silly question, but how do I check the temp in the rad... just dip a thermometer in?

Yes just stick it in the remove the cap and stick it in. :woohoo:
:laugh3: Remember to have a cigrette afterwords and respect your XJ in the morning.

I don't believe running cold is a problem..are you at 160-180 F? You can actually use a little thinner oil since you are in Canada.
Like a 5W-30 synthetic. Oh since you took out the AC, what about the electric fan that comes on with the AC circuit?

AlohaBra said:

I don't believe running cold is a problem..are you at 160-180 F? You can actually use a little thinner oil since you are in Canada.
Like a 5W-30 synthetic. Oh since you took out the AC, what about the electric fan that comes on with the AC circuit?

Click to expand...

running cold is a problem.
If the motor doesn't heat past 170 the ECU won't go into closed loop, wasting gas and making less power.
You also need to heat the oil up so you can get all the condensate water out of the motor.

If you wanted to test to see if its the ac condenser you took out, just take a piece of cardborad or something cover have the radiator with it and drive around see if it heats then.