[love4the2]

My 86 na has been idling around 1,500 to 2,000 rpms even after its warmed up. Sometimes it will drop to around 800 rpms.
I dont know if this other problem is related but my heater blows barely warm air. Is it idling high because the car thinks its not warmed up? I know its a stretch, but I thought the two could be related.

 

[daniel_gabriel]

Make sure your thermostat is working properly. If you haven't flushed the coolant yet, do that. If you have, burp the cooling system and make sure there no air in it and no air is getting into it (read: there are no leaks).
If that doesn't help the problem, make sure there are no vacuum leaks in the vacuum hoses, around the AFM, and the intake manifold. If that doesn't help, make sure your fuel filter and air filter are not clogged up and adjust the idle screw.

 

[fogjammer]

You could have a sticking idle air control, mounted on the throttle body and has coolant hoses attached.

 

[Pantaloon007]

I have the exact same problem and will be changing out the T-stat within the next 2 days. I will post with results.

It might take me 2 days to do it, the Haynes shows it to be a time-consuming process.

 

[kakapoopie]

yea i also have a similar problem, except i replaced my thermostat (didnt take tooo long pantalones)

but i still dont think water is getting by the thermostat...the radiator stays cool, and the radiator pipe is cool. I dont get it. also my engine air bleed valve is jammed shut and the plastic grip is cracked off... any suggestions?

btw my symptoms are high idle 2000-1500 for a long while, then maaaaybe 800 after a while, but then it starts fluctuating 500-800 very weird...engine seems like its shuddering.
also my water temp guage works(i tested it), but it doesnt get any readings from the sensor...it just stays pegged left 24/7 and i really hope its not the sensor $$$


and im a complete noob also and i have no idea what im doing

 

[ITA-MR2]

Long distance troubleshooting is enough of a maze if correct information is transmitted both ways and both parties have an idea what is going on. Lacking any of those bits is like playing "pin the tail on the donkey".

Qusetions:
Has your cooling system been properly bled - to get all the air bubbles out.
Have you checked for ECU error codes?
Have you traced all the vacuum lines (a diagram should be on the underside of the engine cover) and verified correct connection and no leaks?
Is your throttle position sensor adjusted correctly?
Is your coolant recovery bottle - and its cap and hoses - in good shape and properly connected?
Have you checked the throttle body shafts for freeplay (causing air leaks)?

Answers:
kakapoopie - The only solution for a bleeder in the condition you describe is to replace it. They are under $30, new.

Look in the MkI FAQ under topics (most are stickied) like: repeat overheating; cooling system bleed procedure; ECU codes.

 

[kakapoopie]

where can i find one of those? so when i refilled the system, i followed the instructions for bleeding and all that, except i couldnt do anything with the engine bleeder valve...does that mean theres air in there?

any more info/links on adjusting TPS?

 

[ITA-MR2]

http://www.mr2oc.com/showthread.php?t=134559

Search is your friend.

 

[Papo J]

To add to what ITA mentioned above, make sure the throttle body and AFM flapper are clean and free of obstructions (oil, dirt) so they close all the way.

 

[fogjammer]

I bet a dolla donut your motor has air-in-the-head. That bleeder is important.
MR2 cooling systems almost defy the laws of physics and need all the help they can get to run properly.

 

[kakapoopie]

ok well today i was driving it and revving allitle more than usual...and on the way home all of a sudden i noticed some warm air was coming from the AC vents...and i didnt have the heat on. Also at that point it was doing the dam 800-500rpm fluctuating thing. i need to get a thermostat housing(or just the engine bleeder valve) and one of those coolant temp sensors....does anyone have any suggestions for trying to fix the sensor? i remember seeing it turn on randomly when driving...but it hasnt done it lately..and i did the 3.4W bulb test and the guage/wiring seems to work fine.

 

[ITA-MR2]

kakapoopie: I've read your last post 3 times, and it makes NO sense to me. Sorry.

What do you mean you remember seeing the sensor turn on randomly?

You shouldn't need a thermostat housing.

You don't have to have the heat on for warm air to come out the A/C vents - the heat slider controls the heater control valve, but it may not shut off all the way - that has nothing to do with air in the cooling system.

 

[fogjammer]

Air in the system. :thumbdown

 

[kakapoopie]

ITA- i need the thermostat housing cuz 1. mine is really ratty and like jagged worn edges
2. the air bleeder valve is broken 3. one of the BSBV whatever valve nipples is brocken

i didnt know that about the heater thing...i guess it was my fualt.

i meant i remember seeing the coolant temp guage turn on randomly

srry for the confusion/noobness