New to the MR2 world! Have 2 questions

[Bowcop]

Hello everyone!

I am new to the world of MR2 ownership......

I just bought an 85 with about 150K on the clock. I paid 600 for the car. I am having two issues. One is the heater core appears to be leaking and there is a total lack of heat in the car. I know that it is going to be a total pain to change, but I don't see that I have much choice. So the question is.....

Where is the best place to buy one online.............? I did a search on google from various parts houses but not coming up with much.

Second question is...

Once the car is warmed up it idles very weird. It fluctuates (sp) between 1000 and 1500 rpms. This is only while warm...when cold it holds a steady 1100 rpm. I looked for any obvious vacuum hoses not being connected etc. but came up with nothing....

Any of you gentleman know the answers to these questions?

Thanks in advance!!!

Tim

[driftmonster]

Check for vacuum leaks to fix your idle.......The heater core is a pain but there are alot of cheap places to buy parts. I would start with Lithia Toyota...They are board sponsors.

Oh and welcome.

[te51levin]

Originally Posted by Bowcop

Where is the best place to buy one online.............?

Once the car is warmed up it idles very weird...I looked for any obvious vacuum hoses not being connected etc. but came up with nothing....

I would be happy to price out any parts you need. We do not have an online catalog (expensive and error-prone) so you'll need to either email or call me, or post a thread in our vendor forum, under the Sponsors link. I don't use PMs for business - they're too hard to keep track of from work. In fact I had to turn them off because people kept PMing me rather than emailing or calling...

You should make sure your TPS is adjusted properly. On some cars it can cause a bouncing idle if it's maladjusted. Also make sure your coolant is bled properly, because air pockets in the cooling system can also play hell with all kinds of things. If you search these forums you should find instructions on how to do both those things.

[Bowcop]

Thanks you guys for the response! I have an update........... The heater core appears to be holding water now. I did a back flush of the heater core itself and a total flush of the rest of the system.....I cound NOT believe the crap and rust that came out!!! Now she blows nice and hot!...........BUT..........after the flush of the heater core...I had water all over the floor boards. As I write this I have the carpet all pulled up and two fans going in the car to dry them out. Why did this happen during the flush and not when the car is running? I got down there and looked while the car was idiling and not a drop came out from behind the dash. So do I have another problem?

As for the idle going up and down I think that it might be the coolant temp sensor.

Any other opinions?

Thanks again!

Tim

[te51levin]

Originally Posted by Bowcop

As for the idle going up and down I think that it might be the coolant temp sensor.

It's probably possible, but not typical. Check the things that we know cause issues. No sense reinventing the wheel, so to speak, by trying to come up with your own diagnositic theories when lots of guys have already established a pattern of what failure causes what symptom.

[Bowcop]

Thanks for the response, Changing the coolant temp sensor did not change anything......So the next thing I am going to do is Burp the system.....can someone tell me where the TSP is?

Thanks again

[te51levin]

Burping the system involves a special procedure. It is not as simple as pulling the cap off and letting it idle. It must be done correctly or you run the risk of blowing a head gasket, or worse. Instructions are here:
IMOC Articles - Mk1 Cooling System

TSP...? Do you mean TPS? That the Throttle Position Sensor. Located on the throttle body. DO NOT adjust it until you find a full, comprehensive set of instructions.
MKI MR2 Write-ups

Both of these procedures are also covered in the Haynes manual, which is actually pretty good for these cars. If you don't have one yet, I'd suggest finding one. You can probably get one for next to nothing on Half.com etc.

[Bowcop]

Thank you for the burp process!! And yes I meant tps. Thank you for that link as well.........I will get this this running right if it kills me!

Thanks again!

Tim

[transamdrifter]

I just bought an 85 and had the same problem. I am ase cert. Me and my cuzin opened up the trottle body and found that antifreeze / water was not flowing threw the air idel contol system located in the trottle body. Though the problem is usaly in the throttle body becase of calcium build up from using only water in the system; mine was a clog before the trottle body. now it revs ok. but sometimes the vacume hose that contols that valve is not working.

Hopes it helps
Happy new year

[nitrate]

Originally Posted by Bowcop

Thanks for the response, Changing the coolant temp sensor did not change anything......So the next thing I am going to do is Burp the system.....can someone tell me where the TSP is?

Thanks again

look very closly in a manual on your car. ods are the chick at auto world sold you the wrong sensor and or it is in there computers wrong. i know trust me they try to sell me the wrong ones all the time. MR2s have like 5 soolant sensors that can all give you the same problim

[nitrate]

Originally Posted by te51levin

Burping the system involves a special procedure. It is not as simple as pulling the cap off and letting it idle. It must be done correctly or you run the risk of blowing a head gasket, or worse. Instructions are here:
IMOC Articles - Mk1 Cooling System

TSP...? Do you mean TPS? That the Throttle Position Sensor. Located on the throttle body. DO NOT adjust it until you find a full, comprehensive set of instructions.
MKI MR2 Write-ups

Both of these procedures are also covered in the Haynes manual, which is actually pretty good for these cars. If you don't have one yet, I'd suggest finding one. You can probably get one for next to nothing on Half.com etc.

20$ you can BY a funell with a stopper that is made for burbing cars and noting hard abought doing it.

[Bowcop]

Thanks to all of you for the replys! The idle issue seems to have smoothed out. It idles pretty much the way it should now. If the bouncing does occur I just put it in gear and threshold clutch it and it stops.

[Gairloch]

Originally Posted by nitrate

20$ you can BY a funell with a stopper that is made for burbing cars and noting hard abought doing it.

No, it's not hard to do but it is easy to leave air bubbles if you don't follow the directions.

[te51levin]

Originally Posted by nitrate

20$ you can BY a funell with a stopper that is made for burbing cars and noting hard abought doing it.

Those have their place, but just using a funnel like that is not the proper procedure for burping the cooling system on an MR2. There are too many high spots. You have to follow procedure using the bleed valves and clear tubing to do the job correctly.