FAQ: Engine Coolant Temperature & Fan Turn-On

interesting. but i dont know if a power tuner is available for my 95? as soon as i get to my pcm, ill have SINISTER, customize a chip for me ,and ill have the fans and and a few other things adjusted for my mods. anyboy with a 95 out there have a SINISTER chip installed? if so , has it made an improvement ?.....thanks guys

sorry powertuner can't help '95, OBD-I.

But you should look up TunerCat if you want to DIY, or there are other options out there too. Ask SINISTER exactly what changes they make. It's important to know.

dreww wrote:

true, but cant you set your temp settings for the knock sensors on the powertuner? I think mine are stock set for 102*.
I know my engine gets pretty cool without an EGR, and my knock sensors work fine. Engine never gets below 102* im sure.

That was one of the main reasons I got the Powrtuner, but once I found the fan turn-on settings, I knew the 160 was no longer needed. In colder weather, I saw my coolant temps dip down into the 140F range. That's too low. The engine was designed to run optimal at ~200F. It feels odd letting the engine run that cold, especially doing WOT runs. Someone at the DHP forum told me internal engine wear increases by thousands of percent when you operate in this range. My friend at Honda engine R&D also highly recommended against it. Besides, if you can run KR free at 180F, why run any cooler?

My KR sensor turn-on value is -40F I think. If my car is floored below 100F for some reason, I definitely want the knock sensors working!

AA wrote:

dreww wrote:

true, but cant you set your temp settings for the knock sensors on the powertuner? I think mine are stock set for 102*.
I know my engine gets pretty cool without an EGR, and my knock sensors work fine. Engine never gets below 102* im sure.

The engine was designed to run optimal at ~200F. It feels odd letting the engine run that cold, especially doing WOT runs. Someone at the DHP forum told me internal engine wear increases by thousands of percent when you operate in this range. My friend at Honda engine R&D also highly recommended against it. !

i know what your saying, but I think alot of that has to do with the problems you get when you dont ever let your car warm up. Sometimes, people who live REAL close to work and get there before their car warms up can have problems. Even though my car runs cooler than most, it still warms up when I stop or am idling. IMHO, the higher running temps is generally for better gas mileage purposes only. Higher temps help makes sure all the fuel is being burned more efficiently.

96 Riv - Fully Stock - owned 2 months. 179k miles total.
Looks like this:
https://rivperformance.editboard.com/showroom-f3/she-s-a-dirty-dirty-girl-t2698.htm

This weekend I noticed that my Temp seemed to be running a bit high.

Normally, it runs between 200° and 210°, but Saturday night I noticed it creeping up to near 240°, settling there for a few miles, before dropping back down. Up and down about three or four times, on a 25 miles trip.

Sunday morning, I check the fluid levels - all OK. Check Radiator Fan - spinning nicely. Prolly the thermostat crapping out. It's due for an oil change anyway - so I drop it off for service Monday morning.

Service gives me back the car Monday afternoon, saying the same. Everything checks out, and they've replaced the thermostat, along with the oil change, and the temp is now stable at 200°. Cool.

I leave the station to go pick up my son at work, a 25 mile trip...

I noticed a few things, right away:

1) The idle was lower. Previously, the car idled at 900rpm. Now I noticed it *settling* at 900, then dropping to 700rpm when I come to a full stop. Not complaining, but I never noticed it ever drop below 900rpm before.

2) The Traction Control light now comes on (indicating that it's OFF), whenever I come to a full-stop as well. Cripes... what did they do? The light goes back off (indicating that it's back ON), whenever I get back up to 35mph or so, only to come back on at the next light. I flip the Trac-cntrl button on for a bit, and the light stay ON for the duration of the next 5 or so miles, stop and start, implying that it's not the light itself. Trac-cntrl back ON, problem comes back for the rest of the trip.

3) Near the END of the 25 mile trip, as I'm pulling into the neighborhood, the SERVICE ENGINE light comes on, and ACE's patience finally boils completely over.


All of this from a Thermostat replacement, and an oil change? What the heck did they knock loose under there?

I should get it back this afternoon - but in the likely event that they're completely clueless as to what they did - - anyone HERE have a place to start looking?


Driving the Wife's Boat for today,

ACE

Wow, that's HOT! Glad you got this taken care of. Whatever they messed with to trigger the traction light and SES, I'm sure it's far less serious than running the engine at 240F.

A scan will tell them what they did. Hopefully it's an easy fix. Could be as simple as forgetting to reconnect a hub sensor.

Mmm this is too common. Someone brings their car in for work and a bunch of other things go wrong.

Interesting part is.. they shouldn't have been near any hubs or the ABS system to do a thermostat. Unless they leaked coolant (very common) during the change and hosed it down with some poor connections under the hood....that's my guess.

Just got off the phone with the Wife.

Quick version:

Misplaced hose. Fixed for free. Driven about to make sure problems didn't come back. A few gallons of gas tossed in.

Longer version after I get home (including):

WHICH hose - was hooked up WHERE?!?

How MANY miles did they drive it - that they felt the need to gas it up?
(My trip meter said 23 ... We'll see.)

-ACE

I'm guessing it'll say "0".

Hope it's fixed though.

ACE wrote:

Misplaced hose.

WHICH hose - was hooked up WHERE?!?

-ACE

You mentioned you needed about 25 miles to see the issue. When I am test driving a car to find a problem, I'd like to think the customer wants me to duplicate the problem if possible and solve it.

A hose has nothing to do with the ABS/Traction. And ...honestly..I don't see how a hose has anything to do with overheating. How can anyone hook up any hose that deals with coolant, on our cars incorrectly?

they could have misrouted a vac hose.

wonderif you have a pulley binding, like an idler on the accessory belt that drives the water pump.

Albertj

Update
******

I got the car back, and all is well.

The Service Tech was a tad dodgy when pressed for details by my wife.

WIFE: "My husband is asking where the hose was hooked up."

TECH: (sheepishly) "It was a ..... vent."


This really didn't open up any possibilities to me, but at least they didn't seem to be rerouting fluids all over the place.

The car seems fine, and I'm just glad the new thermostat addressed the heat problem promptly.

I trust these guys, as I've been going to them for over a decade, and they're very close by.

Quick followup question though:

My idle is still now at 700-750 - when, since March, I'm accustomed to seeing it idle closer to 900. Not complaining, mind you - as 700 seems more .... economical?

What does YOUR Riv idle at?


-ACE

The manual and AllData do not specify an idle speed, but I believe I see around 850 in Park.

That's normal when in gear at idle. During the winter months, you get higher RPMs when cold, but after warm up, they settle down to about what you're seeing now.

In D my idle is 650-700. In park 800-900. (after warmed up).

Sounds like your fans might not be turning on, I'd check for fan action before replacing the thermostat. If you have your car warmed up (200) and let it idle for a while when do the fans turn on? Turn the A/C off when you are doing this test, the A/C should also trigger the fans so you wouldn't know if it was temp alone making the fans activate.

Fully warmed up in Park, my idle at noon was 800 on the money. I don't think I ever see it less than that in Park.

I just wanted to give an update on the solution to my running hot. I changed my LIM gasket and it seems to be doing a lot better. I haven't had a lot of time to test it, but it seems to be running cooler than it used to.

I got a 97 riv sc and Im always running at like 200 and if I sit at a light for awhile i hit like 210 thats as high as its gotten but should I be running at 200 while driveng, and what can i do to fix it ?

when was the last time you have a coolant flush?

I'm pretty sure the stock fan settings for turn on are around 210 and 226. Also if stock, your car is running a 195F thermostat.

You may want to consider a 180F and having your fans programmed down to 185ish.

Yeah, a stock Riv running in the 200deg range is normal. A little lower on the move, a little warmer when stopped in traffic idling. Follow Bill's advice if you want to cool it down a little. I'm running a 180 thermostat with fan turn-on at 185. My temps stay consistently between 185-190.

Ok so get a coolent flush And a 180 thermostat, can i get one anywhere? and Where can I go to get my fans turned down?

You'll need to either invest in a used (discontinued) DHP Powrtuner, or a new HP Tuners unit, or find someone in the area that owns one or the other. No other options, except to buy a reprogramed PCM from Intense or ZZP.

If you don't mind turning your fans on manually via a switch, the Aeroforce gauge is another option.