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  Topic Review (Newest First)
July 11th, 2019 20:13
sarnodude By the way, I know a guy in Mukilteo with a rebuilt 3s-gte for sale. Time to turbo that car!
July 11th, 2019 20:11
sarnodude
Quote:
Originally Posted by MR2ManiacJC View Post
Just wanted to get back to you and let you know that there was some modifications that had to be made. The radiator and fans fit perfect and everything mounted and bolted down where it should. Even installing onto the car was fine.

However, up top I had to slightly fold the one of the side taps upward in order to clear the big ass bleed valve cap that mishimoto provides. Also I chose to grind down the bottom tap on the hood latch assembly just because it kind of sat upward due to interference with the fan assembly.
I had to do that as well. At least your mounting tabs lined up...I had go use a dremel to enlarge the mounting holes.
April 10th, 2019 19:01
GDII
Quote:
Originally Posted by MR2ManiacJC View Post
Okay so as mentioned before, I bled the car twice just to make sure and even let it sit at idle for over an hour after bleeding just to make sure every bubble was gone. Every bubble was indeed gone and the car never once overheated. My electronic temp gauges read at around 188F which was really good for me. Unfortunately, I did what you said and I popped the cap off when the car was cold. Below is a picture of what I found. . .


Really sucks to find bubbles because there should be none due to proper bleeding so as you guessed it. . . this can only mean one thing
It's not a definite blown head gasket test trick as the coolant at the filler point will move around as it has direct contact with the water pump and circulation system but bubbles from cold normally shows there is a source of gas or pressure from somewhere if the system is fully bled. Bleeding the system with a blow head gasket can be very hard anyway due to the head introducing bubbles constantly.

Sorry to hear it has a blown head gasket. Your chemical test it more reliable than what I suggested.
April 9th, 2019 17:43
MR2ManiacJC
Confirmation of a blown head

Here's how I determined if the car had a blown head.


I bought the block fluid test kit that is commonly used to diagnose blown heads. Its a simple test that indicates a blown head through a change in color for the test fluid. The test fluid is originally blue and should remain blue if there is no compression leak. In the case that the test fluid goes from blue to green/yellow there is a compression leak present aka blown head gasket.

Attachment 65076

Before:
Attachment 65072

After:
Attachment 65074
April 9th, 2019 17:36
MR2ManiacJC
Alas!!!!!!!!!!

Well my friends I am happy to announce that this thread has come to and end because I finally have the answer to my cars problem.

I truly want to thank those of you who followed the thread from the beginning and even shared your thoughts and opinions. I hope this thread serves as an example for future troubleshooters experiencing an overheating issue. Although I wasn't the best troubleshooter I did try avoiding jumping to conclusion and tested different components that I felt could be causing my issue. Unfortunately, I was wrong in the end and it just goes to show that I am no mechanic as I mentioned before. I'm simply a guy who loves figuring out his own car problems regardless of how long it takes.

Conclusion:
The car has a blown headgasket and probably had a bad headgasket for some time now. For any of you who may say, "how did you not know that?". . . I want to be clear that the car never had any symptoms of a blown head. There was never any coolant mixing with my oil on the dipstick or cap, never really noticed a big drop in coolant, never had white smoke coming out of my exhaust, etc. It wasn't until recently that the coolant began overflowing the reservoir to the point that it would bubble and spit out of the reservoir hose as I drove. Apparently this is a symptom of a blown head that I never knew about.

I do want to say that the only real symptom I have ever experienced was a loss of power. Ever since I've owned the car it has always felt extremely slow and nonresponsive. I would always complain about this to my friends but they said it was just a slow car overall. However, anytime I drove other 5S MR2's I could see how nonresponsive mine truly was. Therefore, I think it is fair to assume that my head was probably going bad ever since I bought the car and I just never knew.

It turns out it was never my thermostat, my fans, my radiator, my relays, air in the system, etc. In the end it was just a bad temperature gauge and a bad headgasket.
April 9th, 2019 17:16
MR2ManiacJC
Quote:
Originally Posted by GDII View Post
Try this, not always accurate but if you start the engine from cold with the filler cap off, does it blow bubbles in the coolant? This normally indicates a head gasket leak.
Okay so as mentioned before, I bled the car twice just to make sure and even let it sit at idle for over an hour after bleeding just to make sure every bubble was gone. Every bubble was indeed gone and the car never once overheated. My electronic temp gauges read at around 188F which was really good for me. Unfortunately, I did what you said and I popped the cap off when the car was cold. Below is a picture of what I found. . .


Really sucks to find bubbles because there should be none due to proper bleeding so as you guessed it. . . this can only mean one thing
April 4th, 2019 14:57
GDII Try this, not always accurate but if you start the engine from cold with the filler cap off, does it blow bubbles in the coolant? This normally indicates a head gasket leak.
April 3rd, 2019 19:35
MR2ManiacJC
Quote:
Originally Posted by rmeller View Post
Either the coolant is boiling or the headgasket is ruptured. As for boiling, you already replaced the cap, so the other possibility is that there is a large air bubble in the head that is allowing the engine to overheat. I doubt that, but you can try bleeding the coolant to see if that makes everything right again. If you have all of the air out and it still blows coolant, then it is due to the headgasket passing combustion gasses into the coolant.

I bled the system after installing the gauges for 2 consecutive days. At first I thought maybe its blowing out the reservoir because I have air in the system? But that didn't fully make sense to me. So I went ahead and bled it again the second day in a row just in case. Since Friday of last week I have been driving the car around the city and leaving at idle and what not. The car has not overheated once. As I mentioned, I am reading about 188F when driving and 195F when at idle according to my new gauges. However, I was adding coolant every single day into the water neck because my levels were low since it kept spilling out of the reservoir. I'm assuming that if I stop adding coolant it'll eventually overheat because the levels have gotten so low after spilling out the reservoir. That is why I decided to stop adding coolant in order to test this.

But I suppose it wouldn't hurt to bleed the system a third time. I think I'd rather do a compression test and see if its the head gasket for once and for all. I never considered this because I had no coolant and oil mix on the dipstick or cap, no smoke out of exhaust, and no drops in coolant level. But now my coolant levels are dropping due to spilling from the reservoir and therefore I think it might be worth a try. By any chance have you ever used the fluid block test on an MR2?(The test where the blue fluid should turn yellow if you have a blown head) I'm wondering if the little pump it comes with is compatible with the MR2 radiator cap haha.
April 3rd, 2019 16:46
rmeller
Quote:
Originally Posted by MR2ManiacJC View Post
... The car is throwing a lot of coolant to the reservoir when it gets up to temperature. It fills it all the way to the top and eventually begins spilling it from the reservoir hose as I drive...
Either the coolant is boiling or the headgasket is ruptured. As for boiling, you already replaced the cap, so the other possibility is that there is a large air bubble in the head that is allowing the engine to overheat. I doubt that, but you can try bleeding the coolant to see if that makes everything right again. If you have all of the air out and it still blows coolant, then it is due to the headgasket passing combustion gasses into the coolant.
April 3rd, 2019 14:54
MR2ManiacJC
Update after a long absence

Hey ya'll! As I mentioned a few days ago, I finally have the car back on the road since my last post which was around 2 months ago. There was a lot of rain and I also had no time to work on it until last week. I went ahead and installed two electronic gauges since I could no longer trust my original gauge. 1 of my temp gauges is reading the coolant temp as it exits the engine and the other temp gauge is reading the temperature of the coolant after it has left the radiator. Its been pretty nice to monitor both temperatures and see how my radiator and thermostat are performing

But anyways, I have been driving the car since Thursday of last week. I haven't gone far or to the canyon road yet. I've done nothing but 30 mile drives or so and I am really happy with the temperature of the car. When driving, the temperature exiting the engine is reading at about 188 F. On the other hand the temperature exiting the radiator will read at around 135 F. Only at idle is when the car begins to raise a little higher but nothing out of the ordinary. At idle I can expect the temperature exiting the engine to read at around 190-195F. At one point it even reached 205F but that was only once. It likes to sit at around 195F at idle. On the other hand, the temperature exiting the radiator will begin rising and the minute it hits 179F the T stat opens and I begin seeing both my temperatures drop. So the car is actually acting pretty damn good.

The problem
Unfortunately, there is now a new problem. The car is throwing a lot of coolant to the reservoir when it gets up to temperature. It fills it all the way to the top and eventually begins spilling it from the reservoir hose as I drive. This really is annoying and I can't figure out why it is doing it. I suspected my radiator cap although it wasn't old. So yesterday I went ahead and purchased a new cap but still the problem exists. Most of the coolant will flow back out of the reservoir after the car cools down. The problem is that its not enough coolant flowing back from the reservoir.

This morning I popped the radiator cap off and found that the level of coolant was nowhere near the cap although yesterday it was fully at the top. I also checked the reservoir and it was not all the way up to the top anymore. I wanted to add coolant to the water neck as I have been doing for the past few days but at this point I think the more I add the more it'll send to the reservoir. I am hoping that maybe this is normal and that the cooling system just needs to regulate itself which is why it has been spilling out the reservoir but I dont know at this point. I am going to drive the car without adding anymore coolant and see what happens. Hopefully the issue is that its spitting out because I keep filling the radiator cap all the way to the top but I doubt it.

Any suggestions? One of the MR2 guys in my area said his 3S did that when he had a blown head. But I'm not fully buying that yet.
April 1st, 2019 00:53
MR2ManiacJC Guess who's back!?!?


Again, my apologies for the long absence. The car sat a lot because of the rain and because I had some financial things that had to get done first. I got her back on the road now and will post an update sometime this week!
January 22nd, 2019 12:37
MR2ManiacJC My apologies for not being so active in the last weeks. It began raining pretty hard and around my area the streets tend to get pretty flooded. So I never drive the MR2 during this time. In the last couple of days the rain is finally gone so I will try driving her again and pull over to read the temperature with the temperature gun that I purchased.


I'll let ya'll know how it went.
January 9th, 2019 22:20
naru You probably have air in the system
January 9th, 2019 20:26
MR2ManiacJC
Quote:
Originally Posted by Duality View Post
Wow, haven't been on here in two years - had to reset my password just to answer this thread! Lol. Anyways, I was skimming quickly through this thread so sorry if someone has already mentioned.

I cannot trust a temp gauge anymore after my MK1 blew up with the needle was in the middle - I always check my gauges, but apparently someone said if their is still coolant in that area the temp gauge will only read temp that particular area!

With that being said - I installed an aftermarket sensor that ran into one of my air vents in the dash - after this I was no longer paranoid at what temperature I was at, as I can read digitally what my temperature was! 183-188 was average I believe. I remember it going to 192-193 and I knew something was up, and yep - it was actually leaking from the clamp where my sensor was (so tighten it good!).
Yea man I completely agree. Its just hard to trust these type of things. I never thought an aftermarket electronic temp gauge would be ideal unless I'm tracking the car. I always thought you know maybe the OEM gauge will do just fine for daily driving? But unfortunately, I think my mind has changed. As I mentioned above, my gauge was almost at the red and my car did not feel anywhere near that temperature. If I'm not mistaking, once the gauge is towards the red the temperature is probably around 240 Fahrenheit? So if the car was really at 240 I would have not been able to keep my hand on it even with the slightest touch. I kept my hand there as long as I wanted though. I appreciate the advice and the comment. I'm going to do some trouble shooting with the radar gun. If the gun is not matching the temp gauge I am going with an aftermarket one.
January 9th, 2019 15:32
Duality Wow, haven't been on here in two years - had to reset my password just to answer this thread! Lol. Anyways, I was skimming quickly through this thread so sorry if someone has already mentioned.

I cannot trust a temp gauge anymore after my MK1 blew up with the needle was in the middle - I always check my gauges, but apparently someone said if their is still coolant in that area the temp gauge will only read temp that particular area!

With that being said - I installed an aftermarket sensor that ran into one of my air vents in the dash - after this I was no longer paranoid at what temperature I was at, as I can read digitally what my temperature was! 183-188 was average I believe. I remember it going to 192-193 and I knew something was up, and yep - it was actually leaking from the clamp where my sensor was (so tighten it good!).

I removed this now as I swapped to a Gen4, but read my coolant with a bluetooth ODB2 dongle (wiring done by WireGap) from time to time. Sorry for the lengthy post! Hope it works out!
January 9th, 2019 02:06
benckj No I don’t think the loose over flow cap would let any air in while car was running. Only would let air in when car cools down and forms a vacuum.
January 9th, 2019 01:06
MR2ManiacJC
Quote:
Originally Posted by benckj View Post
Point the gun at any part you want to look for abnormal high/low readings. Saves a heap of guesswork and allows real time diagnois of the engine cooling system. The inlet/ outlet radiator pipes are probably the most important as this will tell the differential between engine temp and how well the radiator (plus pump, tstat, etc) are operating.
I bought a cheap little $40 gun. Tried it out on my scion after a drive. The upper rad hose was reading at 160 F and the lower was reading at about 110 F. So it seems fairly accurate. I'm going to put some water to boil and test take a reading just to get an idea of how accurate the tool is. After that I will take the MR2 for a drive and use the gun. By any chance do you think that my overflow cap coming off while driving introduced air into the system? Is that even possible?
January 8th, 2019 21:02
benckj Point the gun at any part you want to look for abnormal high/low readings. Saves a heap of guesswork and allows real time diagnois of the engine cooling system. The inlet/ outlet radiator pipes are probably the most important as this will tell the differential between engine temp and how well the radiator (plus pump, tstat, etc) are operating.
January 8th, 2019 19:41
MR2ManiacJC
Quote:
Originally Posted by rmeller View Post
It would have been a good idea to refill your coolant after you found the cap off. You don't know how much of it you blew, and that would explain the erratic temperature readings.
Yea I tried to but I accidentally forgot my funnel. So I kind of made a mess and didn't bother trying to add more. I ended up topping it off once I got home.
January 8th, 2019 19:39
MR2ManiacJC
Quote:
Originally Posted by benckj View Post
Yep sounds like a sensitive gauge & possibly sensor. You have also watched like a hawk so are probably a bit paranoid about engine temps. You should buy one of those cheapy laser temp guns to use when diagnosing engine symptoms. Would do a lot for your sanity as confirming if engine, rad and associated parts are above normal temp range.
Yea that's what I'm leaning towards which is a bummer because if this is the issue it could have been a simple fix. The temp switch itself is pretty new though. But about 30 minutes ago I went and bought a new sensor from the local auto parts store. I popped the current one out and put the new one in. The new one was horrible so I popped the current one back in. I did a comparison of the two while I was at it.

The current temp switch: I turned the key all the way without turning the engine on and the gauge read at cold.

The new temp switch: Again I turned the key all the way and the gauge read at hot. This is completely inaccurate because the car has been sitting for hours now and it is pretty cold out. I also felt the coolant with my hands and it is cold so there is no way I'm reading at hot

I never thought I'd say this but I trust the old sensor more so I popped the old one back in and returned the new one.
I'm going to go buy a laser temp gun from home depot and just check what kind of temperature I read around the city first. Do you recommend I point it at the long hose that connects to the water neck? I'm also going to compare it to the hose that enters the thermostat housing since that one will always read colder.
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