Stupid Question about Coolant Ratio

I have a 94 Z28 that has been at the local Chevy dealership for a greater part of a week. They couldn't figure out why my car was overheating. After about $500 they determined it to be a faulty waterpump. They repaired a faulty reading gauge, replaced the thermostat, radiator cap, Sensors, all hoses are new, water pump, did a test that checked pressures in each cylinder and said they are all right on the money and holding 90lbs of pressure, and flushed the system. It was fine for about 2 days and now the gauge is starting to just barely creep into the orange when in heavy stop and go traffic or sitting idle....about 240 on the gauge. It will stay right there on the edge of the orange until I start driving again and then goes back down. I checked the coolant ratio with a tester yesterday and the needle was pegged almost straight up. That would indicate about -100 degree protection lol. So it appears that ratio is off, its probably about 80 to 20. Would this cause the car to get a bit hotter then its supposed to. Like I said it will hold nicely at about 200 degrees when driving but its when I start alot of stop and go that it gets up into the orange and holds. It just barely breaks the orange line. Up until the last month or so it never went passed the last white line which is 220. So it appears as if everything is working ok except maybe the high mixture of antifreeze to water is causing it to get hotter then it should. Can someone please explain the side effects of a wrong coolant mixture. Thanks in advance and Merry Christmas.
Adam

Welcome to AF sonic.

As for your problem, I believe you and your hydrometer are on the right path. Especially since the dealership shotgunned every part of the cooling system possible, BUT the radiator fan, did you make sure it working.

Thanks. I'm finding this forum to be an invaluable source of information!

Yes, I can hear the fan kick on right about the time the gauge hits 230. It is supposed to come on at 228 so its right on the money as well. I took the car back in today and they redid the mixture. They said it is a good 50/50 now and when driving home today it hit the last white line and stopped....so it appears they may have it licked! It will take a couple more days so I can make sure but it seems like its fixed. Thank god, this was starting to turn into a nightmare! Now, its on to find a nice exhaust system to add some extra horsepower, a cold air intake, and to have the throttle body polished and adjusted....every little bit I can get will help! Want to get the most horsepower for the best price without breaking the bank so to speak.
Thanks again

They said it is a good 50/50 now and when driving home today it hit the last white line and stopped....so it appears they may have it licked!
Thanks againSounds like your dealer just throws parts at (at your expense) till they luck in to it. Yes you are correct bout the suspicion that to much anti freeze will hinder cooling. That's why for the D.I.R.T. car we use only water..§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§REFUSE . . TO . . LOSE§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§

Thanks. I'm finding this forum to be an invaluable source of information!

when driving home today it hit the last white line and stopped....so it appears they may have it licked!

It still shouldn't get that hot unless you are sitting for a long time

Well, I thought the problem may have been fixed but it is still hitting the orange line. It will sit right on the very edge of the orange line when sitting in traffic but once I start going again it drops pretty quick. They had my car for 3 days a couple weeks ago and the water pump was the only thing they found to be the problem and they went over the car with a fine toothed comb. I don't know what the deal is with the temp getting this hot. It never used to even come close to the orange before the lower radiator hose burst about 2 months ago. Ever since then it has been a problem. Don't know why? Any more suggestions?

It still shouldn't get that hot unless you are sitting for a long time

is the car running fine otherwise?

Seems to be working fine. Other then a small problem when going through a carwash and the water hits the bottom of the engine it starts idleing really rough. It only lasts briefly though. This is what I think may be a problem with the opti spark since all the plugs and wires are new. Other then that it seems to be running ok.

is the car running fine otherwise?

Coolant temp sensor just went out again. Last night the Service engine light came on and it started running like crap....first thought....coolant sensor. Went back to Advance auto and borrowed there computer and sure enough.....Coolant sensor was bad. This time I went to the dealer and purchased an AC Delco sensor and will see how that goes.

As far as the temp getting into the orange by a hair.....would it hurt to add some of that -30 degree cooling additive. I seen it at pepboys and it is gauranteed to have your car running 30 degrees cooler in heavy traffic compared to antifreeze and water alone. Has anyone tried this stuff and does it really work. If not, are there any suggestions to some stuff that is good and will actually lower the temp.
Thanks in advance

You said that the problem started happening after the lower radiator hose went, who put the new hose on? Are there any kinks or sharp bends in it? That could restrict the flow, infact Ive seen many cars, including my 89 RS, that have a streached out spring in the lower hose to prevent it from colapsing.

What temp rating was the new stat that the dealer put in?..Hay, if they messed up something as simple as a 50/50 mixture, then they could have easily put in the wrong stat, right?

Just wondering, are you using your air conditioning when this is happening? The engine cooling fan is always suposed to be on when the AC is being used, if its not, it could cause the car to overheat very quickly.

Also, did they check your timing, that could do it.
Depending on how many miles you have on your engine, its probably time to change the timeing chain anyway, do it your self, easy way to save atleast $200, probabily 3 or 4 at a dealer.

You also mentioned that the plugs and wires are new, what about your cap and roter, those should be changed too, if you havent already done so.

Just wondering, are you using your air conditioning when this is happening? The engine cooling fan is always suposed to be on when the AC is being used, if its not, it could cause the car to overheat very quickly.

Also, did they check your timing, that could do it.
Depending on how many miles you have on your engine, its probably time to change the timeing chain anyway, do it your self, easy way to save atleast $200, probabily 3 or 4 at a dealer.

You also mentioned that the plugs and wires are new, what about your cap and roter, those should be changed too, if you havent already done so.


Thanks for the reply. I put the hose on. I checked it pretty thouroghly and there are no kinks in it. As of now, all the hoses under the hood for the cooling system are new, the stat should be a 185...I hope that is what they put in it.

Well, I put the new AC Delco Coolant temp sensor on and the error code is now gone. Strange thing is.......my temp is not getting anywhere near the orange anymore...it almost seems back to normal. Not even getting close to the 220 (last white line). HOWEVER......I was in heavy traffic on the way to work this morning and my fan came on at about 200-210 and never shut off. The gauge didn't even come close to the 228 needed to kick the fan in. So now could the new sensor be affecting the gauge reading. Maybe the gauge is not reading correctly and it really was at 228 but the reading was wrong. I don't use the AC at all....has to be recharged. This is really getting irritating. I just want this baby to last about 2 years without sucking me dry of cash lol. New Camaro is coming out (although they say it is uncertain....I GAURANTEE they will put them into production, this car is getting to much attention not to put them into production) and I plan on getting one. So until then I just want my baby to run good. Any help would be greatly appreciated.
As far as the timing, I am not sure if that has been set. I thought there was no way to set that as it is controlled by the computer. The cap and rotor your reffering to may be the Opti spark as It don't have a normal cap and rotor ( I don't think). I am not a mechanic but the Optic spark seems to be the distributor and I am probably going to have that changed out soon.

Just a quick mention, air pockets will cause erratic sensor reading, making it look like it's bad and reading incorrectly.

wrightz28 is correct...DeLoreans have a huge problem with this, to the point that draining and refilling the coolent is a big ordeal which requires some time and effort and involves "burping" the radiator hoses at problem areas to make shure there is no air inside, otherwise the car will overheat and crack the block...
Have you tried burping your upper radiator hose?

BTW: I was mistaken about the cap and roter for your car...my bad.

Thanks for the reply. I put the hose on. I checked it pretty thouroghly and there are no kinks in it. As of now, all the hoses under the hood for the cooling system are new, the stat should be a 185...I hope that is what they put in it.

Well, I put the new AC Delco Coolant temp sensor on and the error code is now gone. Strange thing is.......my temp is not getting anywhere near the orange anymore...it almost seems back to normal. Not even getting close to the 220 (last white line). HOWEVER......I was in heavy traffic on the way to work this morning and my fan came on at about 200-210 and never shut off. The gauge didn't even come close to the 228 needed to kick the fan in. So now could the new sensor be affecting the gauge reading. Maybe the gauge is not reading correctly and it really was at 228 but the reading was wrong. I don't use the AC at all....has to be recharged. This is really getting irritating. I just want this baby to last about 2 years without sucking me dry of cash lol. New Camaro is coming out (although they say it is uncertain....I GAURANTEE they will put them into production, this car is getting to much attention not to put them into production) and I plan on getting one. So until then I just want my baby to run good. Any help would be greatly appreciated.
As far as the timing, I am not sure if that has been set. I thought there was no way to set that as it is controlled by the computer. The cap and rotor your reffering to may be the Opti spark as It don't have a normal cap and rotor ( I don't think). I am not a mechanic but the Optic spark seems to be the distributor and I am probably going to have that changed out soon.

Yes the timeing is adjustable. Just like the prom gives the computer a reference point at which to start, you set the initial timing and then the computer can make small adjustments as it deems necessary. Do you have a Hayes manuel? It will tell you the specific procedure to follow for setting your timing and you can just call a Chevy dealer and ask someone what the timing on your camaro should be set to, unless someone else on the list knows.
Have you checked your fan relay? It may be malfunctioning.
And are you low on oil? Are you using the lowest grade recomended for your camaro? The oil doesnt just jubricate, it is also a key contributer to heat distribution.
Is your car missing the air scoop that hangs under the radiator?
Is there a tranny cooler in your car that sits infront of the radiator? That could also be affecting the temp?

Yes the timeing is adjustable. Just like the prom gives the computer a reference point at which to start, you set the initial timing and then the computer can make small adjustments as it deems necessary. Do you have a Hayes manuel? It will tell you the specific procedure to follow for setting your timing and you can just call a Chevy dealer and ask someone what the timing on your camaro should be set to, unless someone else on the list knows.
Have you checked your fan relay? It may be malfunctioning.
And are you low on oil? Are you using the lowest grade recomended for your camaro? The oil doesnt just jubricate, it is also a key contributer to heat distribution.
Is your car missing the air scoop that hangs under the radiator?
Is there a tranny cooler in your car that sits infront of the radiator? That could also be affecting the temp?

I don't have the manual I usually try to just look things up online...guess maybe I should invest in one.
The car is going back into the dealership tonight to check it out. No charge of course unless it is a new problem that they never messed with the first time around. I hope its just a relay like you said and that my gauge is really reading correct because that would be sweet if my temp was finally back to normal. I use Valvoline Synthetic 5w30 but just placed an order 2 days ago for Amsoil 0w30 and wanted to give that a shot. I have read some really great things about Amsoil and figured...why not....its not much more then the Synthetic I pay for now and if it is even a hair better I will be satisfied. Yes, there is a Tranny cooler that sits in front of the radiator as well. I haven't seen any special air scoop underneath the car unless you are refering to the plastick guard that hangs down in that area. I will let you all know what the outcome is after I get it back.
Thanks for all the input.

Timing instruction s are the emissions label in the engine bay.

Timing instruction s are the emissions label in the engine bay.

Thanks

Thanks to all who assisted me over the last couple weeks and tried to help in determining the overheating problem on my 94 Z28. Much appreciated...

Ok...I got the car back today from Chevy. There is nothing wrong with the car!

They said all the gauges are reading correctly. The fan is kicking on at 228 Degrees as it is supposed to.

???????????????

So I went out and asked the mechanic that worked on my car (who by the way is there TOP mechanic and is also about 60 years old so I guess he knows what he is talking about) why is my fan coming on when my gauge is reading 215 degrees instead of the factory setting of 228?

He said that the factory Ac Delco Coolant temp sensor that I installed actually has some type of Diode or something in it that doesn't let the gauge go up to the orange line like it has been doing. This is due to the enormous amount of complaints from people with cars with the LT1 engine saying that there cars coolant gauge is getting up near the orange during heavy traffic. Although it is not overheating, most people didn't like that. So Chevy redesigned there Temp Sensor to fool the gauge.

Now, this kinda makes sense to me. Because when the first hose went bad the Coolant temp sensor had to be changed to because I received the Service engine light. I replaced the sensor that same day but purchased one from Advance auto parts for like $9 or $10 dollars. From that point on my car has ran hot....well, gauge teetering on the orange line in heavy traffice. Then it finally overheated and that is when all the major work was done on it with the water pump and everything. I got the car back and it was still teetering on the orange line in heavy traffic. So since it wasn't staying there I continued to drive the car as it ran normal. Then the other day the service engine light came on...indicating a bad Coolant temp sensor. This time I went and got one from the dealership, AC Delco. As soon as I put this in the Temp never went over 215 degrees no matter what the driving conditions were. I did hear the fan kick on though and my gauge was at 215. So I took it to the dealership thinking my gauge was wrong...and this is when they told me about the Coolant temp sensors that are made to keep the car from appearing as though the temps are not out of spec. So when I put the el cheapo Advance auto temp sensor in...the readings were how they used to be before GM engineered a new temp sensor to prevent this problem that I have been dealing with....

Does this make sense to anybody....I mean I can really believe it because of the car going back to normal after putting back in a factory sensor vice another El cheapo.

Please let me know if this sounds legitimate to anyone else....either way I'm happy. They said the car was fine and they checked everything out and then explained about the sensor to me. Looks like problem is solved and my baby is running great again....or always has been lol.

Next step......A new K&N CAI...and a new Exhaust.

Any reccomendations on an exhaust that would give a nice HP boost and sound really good would be greatly appreciated. The more HP I can get from the new exhaust the better....I'm sure this should be another thread in the performance sections but just thought I would throw this out since I have typed so much...lol.