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jflynn13
01-04-2009, 10:00 AM
Hi all,
the car runs ok but it is running well below normal operating temperature. The heat works and there are no codes. I replaced the ECT and the sensor that send the signal to the gauge with no change.
the cooling fan is always on, not sure why.
there is also very little pressure in the radiator lines when running. then engine just does'nt get hot. it has been pretty cold out for a while so I am sure that plays a small part.
I am having some electrical issues which I posted here (http://www.sccoa.com/forums/showthread.php?t=104452)
Any ideas are very welcome.

NEEDaSCbad
01-04-2009, 12:52 PM
I think I'm having the same problem. I just replaced the radiator fan a couple days ago cuz the stock one shorted. The new one stays on? why? The old one might have too and i just didn't notice. I have noticed that my temp guage never gets much above the cool mark (i always thought the gauge was broken). what kind of problems could be caused by the car never really getting "hot"?

jflynn13
01-04-2009, 02:47 PM
I guess I did not see this (http://www.sccoa.com/forums/showthread.php?t=104254&highlight=cool+upper+hose).

Going to go check it out and see if that is my problem

Jeremy_K
01-04-2009, 08:25 PM
I guess I did not see this (http://www.sccoa.com/forums/showthread.php?t=104254&highlight=cool+upper+hose).

Going to go check it out and see if that is my problem
Yeah, try using studs when you re-install it. I'll be doing that from now on.

jflynn13
01-05-2009, 08:48 AM
I pulled the thermostat and reseated it, no change. The thermostat is only a couple of months old. Could this be caused by air pockets?

Jeremy_K
01-05-2009, 04:57 PM
I pulled the thermostat and reseated it, no change. The thermostat is only a couple of months old. Could this be caused by air pockets?
Yes it could be air. To bleed the air I usually elevate the front end a little bit, Open the bleeder screw, put a funnel in the radiator neck and pour in the coolant keeping it full and tight to the neck until a steady stream comes out of the bleeder. Then close the bleeder before you pull the funnel out. Drive it around for a bit to warm it up and when it cools down, repeat the process if you need to. The overflow reservoir should be filled to it's normal level before filling the radiator.

jflynn13
01-06-2009, 03:23 PM
I bled the system. When I drove the car a little hard it did heat up. Not the guage climbs about mid way. The odd thing now is the hotter the car gets, the colder the air coming out of my heater is. Bad water pump?

decipha
01-06-2009, 03:39 PM
first signs of head gasket failure

KMT
01-06-2009, 03:41 PM
>The odd thing now is the hotter the car gets, the colder the air coming out of my heater is. Bad water pump?

What is the outside temperature there now?

DrFishbone
01-06-2009, 05:30 PM
the cooling fan is always on, not sure why.

I've not had to deal with this, but check out IRCM problems...also, some people cut a fan wire to achieve this. The cooling fan on my cars hardly ever come on - I know because they're so noisy when they do! :) If your fan is always on, this definitely contributes to your problem.

jflynn13
01-06-2009, 05:57 PM
Actually, what i said about the heat was not accurate. above 2000 rpm the care throws out heat. The guage does not go above the "o" in "normal". When I got home today, I could put my hands on the radiator and the upper/lower hoses, so it was not that hot. The radiator and resovior are full but the hoses felt as if they had no pressure in them. What I'm thinking is either the thermostat is not opening or the water pump is shot. Are these symptoms consistent with either of those problems?

The head gaskets have less than 20k of easy driving on them. I blew the gaskets on my 90 and the symptoms were total different. due they have different symptoms if they blow in different places?

KMT
01-06-2009, 07:17 PM
>What I'm thinking is either the thermostat is not opening or the water pump is shot. Are these symptoms consistent with either of those problems?

Actually, if the thermostat wasn't opening, I'd expect the system to overheat. If it shifted in the housing, or stuck open, then it might cause the engine to run cool by not supplying enough backpressure in the system.

I've seen water pumps with impellers that were almost missing as a result of excessive corrosion etc. Pull a hose and peek inside or just pull the pump itself.

DrFishbone
01-07-2009, 08:21 AM
Yeah, if your t-stat was stuck closed you'd be having high temp troubles. Stuck up (or too easily opened - too low of a temperature setting - 160 - or worn spring?) would cause the coolant to stay cool...especially in cold weather. How long have you had the car, and are you sure what temp. t-stat you have in it? 197F is stock I believe...some other common temps are 180F and 160F...I'm sure there are several others as well. Maybe you got stuck with a 160?

Jimmy 2Coupes
01-07-2009, 01:01 PM
The first thing I would address is the cooling fan always being on. If the fan is always on the coolant temp will always show low on the gauge unless you drive the piss out of it....especially this time of year.

Cougarfetish
01-08-2009, 01:01 AM
Hey there,

Don't wanna hijack at all, just wanted to chime in and say I'm having the same problems. It's cold here right now, but even in the fall it didn't warm up quickly. I need about 45 mins of driving to get the temp guage up to the "O" in "normal". Heat is not very hot until the car warms up, but it's hot when it gets there. My buddy just figured someone installed a colder tstat, but after reading this post I'm not so sure. I'm anxious to see how it ends up for you.

By the way, I'm driving a 90 XR7.

Cheers,
Derek

19TbirdSC91
01-08-2009, 04:02 AM
This is somewhat off subject, but do the cougars tend run cooler than the tbirds since they have the grille and all?

DrFishbone
01-08-2009, 08:20 AM
Don't wanna hijack at all, just wanted to chime in and say I'm having the same problems. It's cold here right now, but even in the fall it didn't warm up quickly. I need about 45 mins of driving to get the temp guage up to the "O" in "normal". Heat is not very hot until the car warms up, but it's hot when it gets there.

Does your fan stay on all the time too?

jflynn13
01-10-2009, 06:08 PM
I want to see how this ends up for me too. The car is in garage and I am pulling the water pump later on. I will let you know what I find out.

Jeremy_K
01-10-2009, 10:24 PM
This is somewhat off subject, but do the cougars tend run cooler than the tbirds since they have the grille and all?

Since my cougar now has a tbird hood, I have not noticed a difference. But then again, My tstat wasn't seated correctly so it always ran cool.

Raymondo
01-14-2009, 12:22 AM
Any news on this? I have noticed that my SC is running very cool but then again it is windy and in the 20s here.

slowpoke
01-14-2009, 09:19 PM
Your fan should not run all the time. The only times it should run is between 185-220, or if the AC is on then it will run non-stop. If your fan is running non-stop then yes it will be tough to get to normal temp. Find out why your fan is on non-stop run and fix it. Might i also suggest for winter driving slide a piece of sheet metal down the front cover half of the radiator. I got that on my and it still takes some time to warm up, but its not to bad. Just keep in mind this car has a far better cooling system on it then what it really needs. So by all means if your fan is stuck on, its going to run very cold.

jflynn13
01-17-2009, 09:30 AM
Turns out the water pump was not crapping out. The Harmonic Balancer broke a few months ago and I am guessing that lead to the eventual failure of the pump. After I pulled the pump off i tried to turn the it by hand, which did not turn smoothly. New pump and thermostat and good to go.

The fan running all the time has to be related to the short in the electrical system. I can't find the damn short. I will tackle that one next.

jflynn13
02-15-2009, 02:55 PM
The water pump issue is solved but I still can't figure out why the fan runs non-stop. It's keeping the engine from reaching operating temprature, which is causing code 51 (ECT) to appear. The ECT sensor is brand new. Any thoughts on why it would run all the time?

I did not cut the wire, it just started running all the time.

jflynn13
02-15-2009, 10:54 PM
A little more information about this problem. I was getting an intermittent code 51 ECT, so I changed the sensor today (took it off my 90). I also pulled the IRCM and gave it a loving tap (well, maybe more than one). I reconnected it and behold! the fan did not start running when I started the car. I drove it around after it warmed up, got on it just a little bit and the CEL popped on again, Code 51 and 24. both leaning towards the ECT.

When I started the car again, no CEL. Any thoughts on what could be going on here? I any needs any more info to help me solve this, just let me know.

James

KMT
02-15-2009, 11:56 PM
>Any thoughts on what could be going on here?

There are relays inside the IRCM - if tapping on it makes them behave until they heat up, then it sounds reasonable to plan on checking the harness and swapping it out with a known good one...at least long enough to test.

jflynn13
02-17-2009, 12:31 AM
The code 24 is no longer an issue, BUT, of course it had to be replaced by another code. Heaven forbid I own an SC without codes.....

I still getting code 51 (ECT) and now getting lean condition (code 41) The CEL comes on once in a while and those are the codes stored. Now the idle fluctuates (raises and lowers) between 600 and 1400 rpm then levels out after a while. When it's doing its idle thing and i hit the gas it starts to stall but doesn't actually stall.

I thought fuel pump but that would not cause a lean condition on one side, right? The car had an EGR but it was removed before I got the car. The EEC if from a 90 with no EGR. I could not find any leaks at the block off plate and the vacuum is solid (no apparent leaks)

Could be a bad HEGO but my gut tells me it is all related.

I defend the honor and virtues of my car to the end, but in private, when no one is looking, I curse at it!!:D

jflynn13
02-17-2009, 10:00 PM
Just in case anyone was/is following;
what I'm thinking happened is, the fan was on at all times, not allowing the car to reach operating temp and keeping the eec from entering a closed (open?) loop.

I Smacked the IRCM, un-sticking it. The car then reached operating temp and started giving lean condition (code 41). Makes sense because the eec ignores the 02 input until it reached closed loop operation.

I ran a KOER, cylinder balance test and only got the code 41 and 51. same as before.

I had a feeling there was a common factor to of this so I started at the basics. Ground. The Ground bus right near the IRCM was all crapped up. I cleaned it up with an angle grinder:eek: (not really) and reconnected it.

I let it warm up and drove it around town and on the highway for about a half hour and no CEL ot codes so far. Unless something happens tomorrow, I think I found my issue.

jflynn13
02-25-2009, 09:08 AM
I hate to drag this back up but I am still having issues with codes 41 and 51. They keep coming up.

The cel comes on after about 15 minutes of driving, regardless of how I drive the car. Even if I reset the eec it does the same thing.

The ECT sensor is brand new (so was the one it replaced). The only changes to the car are:

EGR was removed before I got it. I put the EEC from my '90, which has no EGR.

Has anyone else run into these issues?

99GSXR750
02-25-2009, 11:57 AM
When I had a lean condition on the drivers side, I replaced the o2 sensor and all was good.
As far as ect, couldn't tell you. That may be a wiring issue. I know with it unplugged, the fan will run constantly.
Were either of these codes present before swapping the ecm? Switch back to see what happens.

jflynn13
02-25-2009, 06:15 PM
The only codes I was getting were 24 (EGR) and the ECT code. The fan was always on before I swapped out the computer. The previous owner removed the EGR but failed to change the computer. Once I changed the computer, the EGR code went away but the ECT code stayed and the Lean code popped up.

If I am not mistaken, the EEC ignores the 02 sensors until it reached operating temp. With the fan always on the car never got hot. I could drive an hour to work, with stop and go traffic and take the radiator cap off when I got to work. That kind of cool. Now the fan runs when it is supposed to and heats up like it should.

The car does choke for a second aroung 9psi of boost, but that's it.

any thoughts.

89SCBoosted
02-25-2009, 10:25 PM
i believe its an air trap by the coolant temp sendor to your gauge, they're not very acurate unless fully submurged in the coolant. if you can scan it, it will tell you you're engines acual running temp via the coolant temp sensor..

jflynn13
02-27-2009, 07:56 AM
i believe its an air trap by the coolant temp sendor to your gauge, they're not very acurate unless fully submurged in the coolant. if you can scan it, it will tell you you're engines acual running temp via the coolant temp sensor..

I not sure I understand. how does the temp sender have anything to do with the ECT being out of voltage range?