I put brakes on last night.(raybestoes QS). after doing this i decided to reset my ecu and get the code. I DId. it came back with 9long and 8short / 1long and 3short ::Engine Coolant Temperature Sensor.

Ok the car ran fine before i reset IT. The check engine light went off. and i started the car and It Barely Stays runing. 300 RPMS.

I Reset it twice again.back to back like im supposed to.
Still It barely runs. @ 300rpms.
When it idles The RPM's move from 300rpms to 500rpms constantly, but like every 2 seconds...

Now the check engine light is off. i get the same code i got 2 weeks ago when i set it 5long and 5 short:: undefined or reset.

WHY Is My car acting UP? WHY WHY WHY? if it was a girl i would smack it. and yes i did do all maintence this year.like fuel filter, factory plugs, oil pressure switch, TB cleaning, + QT gas w/IQ

thankyou.mdub.

 

is it a ruff idle kind of like its choking. did u turn the screw back all the way to its stop position.

 

yeah , i tried resetting it like 3 times. im almost sure that i turned it to the original position. im so sure b/c i did i like 3 times.
Is this code:Engine Coolant Temperature Sensor.. the prob..
In the MORNing it barely starts too. I adjusted the idle to go to work tonight.

 

I would say the temp sensor is the problem. The ECM reads the temp of the motor to provide the correct amount of fuel, timing etc.......

Change the sensor and go from there

 

yea that could be the problem fix the sensor and see what happens. Also i don't know if this has anything to do with it, somebody correct me if im wrong, but you might want to clean your throttle body also.

 

This happened to me also with the low idle after checking codes.

I think you have to move the screw back and forth twice in rapid succession to get the ECU reset correctly. I think the instructions are in the FAQ section.

 

you probably left the ecu in diagnostic mode, once you get the codes, you have to repeat the process of turning the screws again before you start the car to completely reset it or it will be stuck in diagnostic.

 

could very well be a bad coolant temp sens. Cold start idle relies heavily on this sensor and the ECU makes the proper adjustments.

something i learned the other day from Q45 master tech is that even if your thermostat or coolent temp sens seems to work properly you should replace it after about 100K miles. If it is acting prematurely you could be loosing up to 1-2 mpg in fuel. Amazing how one sensor can make the difference. You guys should add this to your 100K mile maintenance list.

 

ok guys i replaced the engine coolant temp sensor.
I reset the ecu like 4 times.

It still wont start in the morning. i have to put my foot in the gas to get it too start. whats going on.... i turn the screw twice in a row real fast to reset the ecu.i tried doin it slower too twice in a row..

Does anyone have any pics of the correct position...
SOmeONe HELP please..

 

HOW do ya'll fit underneath the steering column to get to the ecu codes??? I'm a small guy, and I still can't seem to get underneath it with all the pedals, and I got no arm room to use the screw driver, and i can barely see the screw.

 

rofl n00b....lol umm, are u auto or 5spd? basically, just take off the cover for it, get a flash light down there or some other kinda light, and break the plastic off if you havent already...then with your left handle w/screwdriver in hand, go under the pedals then once you clear them, go to the ECU

 

It is a very tight fit. I've already removed the cover and all that good stuff, and it is still pretty tough for me. I got some hand-held device that reads the OBD2 codes earlier tonight, and the errors it reads are that the o2 sensor after the cat isn't read, and that the voltage it puts out is high...kind of odd. Any input??

 

your supposed to turn the screw all the way, keep it there for a few seconds then return it back to the original position. repeat that 2x

 

with my first max, my idle would be real nasty after resetting if i didn't turn the screw all the way like u supposed to...i think the car's brain is like half on...if u put it halfway....

 

turn it slowly! after you are done with diagnostic mode turn it fully counterclockwise. look at the dash and make sure the CEL is lit, but not blinking. if that is all correctly done then it's not the ECU. you really have a mechanical problem. i had that same idle problem two weeks ago and thought it was my alternator. good thing i got it replaced because it was on its way out anyway. good luck.