Intake / temp question

torch

Tech Guy
Staff member
I got the car out on the road the other day, noticed the temps seemed high.

On highway in 6th gear, cruising at 120, manifold temps climbed to right around 220F. Intake temp was at 98F. When I exited the highway, temps dropped to 180ish. Didn't think much about it, but I noticed it because that's what I had on my screen at the time. It seems high.

I checked the obvious things; coolant levels are good, nothing blocking the CAI. What am I missing?

IMG_0818.jpg
 
how much boost did you have at the time - I’m thinking it was low during the cruise phase ?
Is the water level in the inter cooler tank still good as well?
Is the pump running for the inter cooler system? Lack of water flow is most likely to carry the heat away

If the intercooler has its own fans - are they running?
 
how much boost did you have at the time - I’m thinking it was low during the cruise phase ?
Is the water level in the inter cooler tank still good as well?
Is the pump running for the inter cooler system? Lack of water flow is most likely to carry the heat away

If the intercooler has its own fans - are they running?

well.... it was actually after a full boost, short pull in 3rd gear, so i'm sure that contributed to it. I'm going to try to repeat this without boost and see if I get the same result.

water levels are all at the correct levels. Pump is running on the intercooler, observed. Fans are running.

The thing that confused me was that the temp levels dropped fairly quickly as soon as I exited the highway. Could my low gear ratio in 6th gear combined with 3.31's be overworking the engine at < 2000 rpm?
 
Anther thing that can affect it and simple.
is thermostats in some cars can stick,
so if its not opening properly might cause bad
or no flow for cooling. Sometimes just stick
and relatively easy to change of required.
 
IF you have a SC, there are two things, obviously heat of compression when boosting. Second even when not in boost the inter cooler circuit has been previously heat when boosting. This will warm the intake charge. I expect your air temp is measured after the SC. You must have added a SC?
 
I'm going to take it for a drive later today and do some more testing, i'll report back. I'm sure it will be helpful if I provide a more detailed set of information.
 
Yup, aftermarket SC. I don't actually know where the temp is being measured.
I am no expert for sure. I just cleaned some sensors on my truck and there are three, one t the inlet after the filter, one before the throttle body and one after the Throttle body. So who knows what they all do.

I do know that the biggest down fall of SC cars is heat soak. So when the air is cold and the car has not been run hard it makes good power. However when the car gets hot and the inter cooler loop temperature raises performance drops as intake temp rises. This will generally happen when doing laps and using lots of boost.

So when you coast for a while the temperature will drop and then back to regular power levels.
 
Stupid question, but I presume filter is clean, clogged would give dirty air and less
fresh after heating system. So many little things it could be.
Is it cooling, even if slowly after running it with boost.

Should not get too hot with short pulls and considered outside temps.
 
Is it cooling, even if slowly after running it with boost.
Should not get too hot with short pulls and considered outside temps.

Everything looks pretty clean

Assuming the check engine light that's on in the picture is normal due to your setup?

It's a throttle thing that I need to clear once in a while, it's harmless but yes related to the tune.


Ok, took it for a spin again tonight. For reference, TC Highway is close to my place so I was fully warm by the time I got to it.
Here's a breakdown of what I did and temps:

190F head, 75F inlet
Merge onto TC Highway, no boost used at all. Cruising at 120km/h in 6th. Vacuum gauge reading between -5 to -10, maybe a small blip up to 0 on a cresting hill.

212F head, 77F inlet
After 2.5km of driving on TC in 6th gear.

221F head, 82F inlet
After another 4km of TC in 6th gear.

226F head, 88F inlet
After another 3km of TC in 6th gear -- exiting and turning around to head home.

205F head, 86 inlet
By the time I reached the stop sign on the off ramp

196F-198F, 86 inlet
Cruising back to home, but this time in 5th gear only. Vacuum reading at -20ish the entire way.

190F - 210F
Another 5-6km drive through town, 50-65km/h, including several stop lights and a mcdonalds coffee pickup. One chevy pickup caused me to go hard through 2nd gear for about 3 seconds and that brought me up to 216F.

That's all i have.
 
Yes, from what I understand the larger number is the engine coolant temp which is after the SC. I don't think there are any issues with a bypass, the vacuum gauge is active and responsive.
 
To me its one of two issues.
Sensor not working correctly or
flow issue, if coolant not moving properly,
temps go up.

you should not have that high of temps in this
weather. so not cooling right, unless something reading
it is not working correctly.
 
I think I have misunderstood your numbers


If the larger number is engine coolant temp , not supercharger air temp you have nothing to worry about . Today’s engines often run 210-225 normally coolant temp when under load . The fans normally don’t come on in a stock tune until 225+ or a/c on. The coyote from what I see regulates inlet temp - cold water is from rad is not sent to the engine until inlet is over 180f. load determines the outlet . I think this engine will actually code if it runs too cold! Low RPM in 6th means lower water pump flow and more temp rise .
 
That makes sense. Maybe I was panicking over nothing. I know the reason this got me anxious in the first place was because of my foxbody, that thing would climb to 215 when idling in traffic and it felt like it was on the edge of having a nuclear meltdown, lol.
 
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