Mx3 94, KLZE - Rollercoaster idle & running hot

[technich]

Ok, i checked that weird pipe out a bit... heres a picture, right under the disty, then it goes up a bit just above the termostat housing... small metal cylinder sitting on the housing with 2 nipples, one nipple goes to the pipe and other nipple goes to the IAC, couldnt get a good picture

So its going from IAC to the water reservoir, that cant be correct setup can it?



I have now moved the hose from this pipe and put it on the radiator nipple

So now it looks like
Rad. nipple -> Reservoir
IAC -> The pipe -> goes nowhere??????

It kinda feels like i should be able to plug this pipe, just a hunch

This could be the thing causing strange idle or am i way out?
Thanks for your help!

[davmac]

I’m not sure if that pipe even carries or should carry coolant. That might be part of the vent piping from the rear valve cover.
Surging idle and overheating could definitely be related. Both can be caused by low coolant or air in the coolant .There is a coolant temp sensor near the radiator fill neck that must be submerged in coolant or it will send the engine control unit erratic signals and cause the surging idle. Low coolant level or air in the coolant will also cause the engine to overheat.
Your EGR has coolant input and output hoses – maybe those are misconnected. Coolant hoses should connect from engine block to IAC, IAC to EGR, EGR to coolant bypass pipes near the thermostat. Coolant needs to flow through all that stuff to cool your engine.

[technich]

Im getting closer!
i plugged that pipe and bled the coolant and been driving it with normal temp for 2 hours now, and idle got alot better, but there is still some problem with the idle, but now only when i turn the steering wheel, if i turn it all the way left or right it idle 300-500rpm higher when car is idling, any ideas?

Kinda feels like the power steering gets to much power in it.

[davmac]

What you describe I believe is normal. The ECU will increase power assist at idle and wheel cranked to full left or right.

Is your idle now smooth and around 600 - 700 rpm when the engine is warm?

[technich]

Nice to hear

Havent fined tuned the idle yet, had rather high idle before to keep it alive, atm its around 1000rpm and steady. runs really good now, i actually thinks its getting better and better.

gonna adjust the ignition timing and idle this weekend, damn im happy that it finally runs smooth. installed it ~5 years ago and finally im done

when i grow up im gonna be a mechanic!! hehe

Thanks again for the help.

[technich]

Solved