I'm sure this subject has come up many times, but after checking the latest posts, I've realized the symptoms described there are different from my problem. As mentioned in the subject title, the car is a 95 Contour GL, Duratec ATX. I can't give more details because it's not mine. The problem is that the idle goes up and down between less than 500 and 1000rpm even when cold and sometimes the down motion is so much it stalls. The car seems ok while driving, with normal throttle response and power, but when stopping and not pressing the gas, the idle starts going up and down about once or twice per second until it stalls. Interestingly, when I disconnect the MAF sensor the idle becomes stable, albeit sometimes getting up to 1000rpm, but at least it's drivable and the engine performs normally. I left the MAF sensor disconnected so my friend could drive home without having to press both gas and brake when in a traffic light. Could someone help me? Is driving with the MAF sensor disconnnected a bad idea?
Thank you!
Sounds like symptoms of bad TPS sensor.... But I'm not sure why unplugging the MAF would help if that were the case.
Well, since unplugging the MAF actually improves the situation, I'd say a dirty/malfunctioning MAF would be the top of the culprit list.
Take the MAF off, spray some electronics (or brake) cleaner on the two little elements inside the MAF (don't take it apart), remove the negative battery cable for a minute or two, and see if the situation improves when you put it all back together. Best to pull the battery cable before removing the MAF and put it back on last.
You could also try spraying the connectors (both MAF and harness) with some electronics cleaner. Maybe the contacts are dirty/corroded.
For the cost of a can of spray cleaner, it's worth a try.
i had the same problem and seemed to get rid of it cleaning the throttle body and egr
I AM STILL HAVING THE SAME PROBLEM. I CLEANED THE THROTTLE
BODY (IT WAS ALL GUNKED UP) THOUGHT THAT WAS IT. I USED TWO CANS OF CARB CLEANER. I PUT EVERYTHING BACK TOGETHER AND SHE SEEMS TO IDLE BETTER WHEN
SHE IS WARMING UP. BUT I STILL HAVE THE PROBLEM OF WHEN
STOPPING AND SHIFTING. (I HAVE A STANDARD 95')
WHAT AND WHERE IS THE MAF CENSOR? WHO MANY OTHER SENCORS COULD IT BE?? I HAVE READ IN OTHER POSTS
ABOUT AUTOZONE DIAGNOSTIC. ARE THE TECHS ABLE TO READ THE CODES OR DO THEY JUST GIVE THEM TO YOU TO FIND OUT FOR YOURSELF? WOULD THEY HAVE A DIAGRAHAM OF WHERE THE PROBLEM IS? WHAT DO YOU THINK gdub520????
Whoa!!!..
First off...
Step away... from the CAPS... (Gives a sense of yelling, and an overall "loud" appearance, making it harder to decipher relevant information from your post..)
Firstly:
The MAF sensor can be located be finding your air filter. (In a black filter box.. Just towards the engine, will be a roughly rectanglar box mounted to the MAF(Mass Air Flow).. You should see a small sensor on top of the box, with wires leading to it.. This is the MAF Sensor.
The MAF is the first physical thing, after the air filter...
Secondly.. The Autozone tech will read and "attempt" to tell you what your code means.. He basically reads what the screen tells him to say.. That's about it.. Make sure to grab that code, and post it here, so that those of us with MUCH greater knowledge on the topic will be able to help you out.. plenty of people on here, and a lot of past incidents..
I doubt Autozone will have diagrams, but WE may, if we know the code..
HTH
Ray
Thank you for the comments. This problem is confusing me because it seems just the idle is affected, so this should lead to the idle control valve. However, since it gets much better after unplugging the MAF, then it can also be the MAF. I haven't considered the EGR valve, but after reading the comments maybe I should. Can the EGR be cleaned with electronic cleaner spray? How about the intake manifold gasket? I've read another post where this is suggested as the cause of bad idle/stalling.
Thanks again.
sorry, i can type better if i don't have to worry about the
caps. i'm a wanna be mechanic not a typist. hows this---
calming effect???
i'm gonna try your suggestions. i see alot of people use auto zone i'll get the codes and come on back to this helpful group.
tilly
check the IAC "idle air controller"
Originally posted by showtime:
check the IAC "idle air controller"
Definitely...the IAC (as I understand it) is like a regulator-type sensor for airflow at idle, and if it's gotten sticky or sludgy, it won't respond properly to airflow restrictions. Mine's being replaced today, in fact, and I had the EXACT same symptoms.
No need to go to Autozone to have them "pull the code" as with the 95's (and only the 95's) you can pull the code yourself with just a paper clip and few minutes of time. Read thru
THIS information and it should tell you how to run the test and what the code will tell you.
The part you need to clean on the MAF will be easy to get at from the air filter box. Just pop the top and look down the intake for the vertical bar with the sampling 'horn' on it. Spray the parts cleaner into the little horn.
Check the bypass hose that goes from the accordian tube to the IAC valve for cracks/leaks before replacing the IAC valve itself. These are about $80 new and won't work any better than the old one if there are any leaks in the hoses.
I also cleaned the throttle body that was gunked up.how do you get to the intake manifold gasket?
HEY I REMEMBER DOING THIS IN VO-TECH CLASS YEARS AGO.
NOW I REMEMBER WHY I BECAME A MACHINIST INSTEAD OF A MECHANIC!!!!!! I'm game for anything.thanks.
TPS=Throttle Position Sensor. It's located on the throttle body and indicates how far the throttle is open. You may want to unplug-replug the connector to it to make sure you have a good connection. You have to remove the entire upper intake manifold to get to the gaskets underneath. Lot's of stuff to disconnect & take apart. (Recommend getting a manual if you haven't done this before...)
BTW: Look up CEL codes
here
I cleaned everything on, in under the throttle body sooooo
i must have cleaned it. Guess i better check it!!!
if u've cleaned the throttle body did u also clean the egr passages in the intake manifold behind the t/b??? for my car thats all i did and it worked...this problem seems like its cropping up alot recently on the site...other suggestions are to check/replace the sensors as mentioned...if i could i would replace the sensors anyway, since that seems to be the rememdy...i did a necessary cleaning but im not smart enough to know if that'll keep the problem from returning
YEAH, ALREADY DONE. I'M BEGINNING TO THINK SENSORS. I THINK THE CODES FROM OTHER POSTS WILL HELP DETERMINE WHICH
ONE IT IS.
Well, the car (95 Cont LX V6 ATX) seems to be working ok now. What I did was remove the metal section where the MAF sensor is and spray STP throttle-body cleaner. I don't think it made much of a difference because it wasn't dirty. I also checked the throttle plate and sprayed inside it as well. I could see a lot of gunk on the back of the throttle plate and immediately behind it, in the intake plenum. I couldn't clean out the gunk completely but I did spray profusely. I wonder how badly all that gunk is affecting engine performance. Finally, what I think did it is a little hose that connects to the big rubber hose between the MAF and the throttle. This little hose was disconnected and I'm not sure if it was because of all that fumbling or if it was indeed the cause of the problem. I tend to believe it was the cause. I connected the little hose (after not a little cursing, cajoling, huffing and puffing, and more cursing. Damn, that was hard!) and after tightening everything, voila! the car started... and then spluttered and stalled. It did that for a while until all that throttle cleaning fluid I had sprayed so liberally got consumed by the engine.
In retrospective, and having read some more of your replies, I think the little hose detached was all the problem. By disconnecting the MAF sensor I think I made the EEC-V run in some kind of emergency mode that was actually better than having it connected. I think the little hose is the bypass to the idle control valve. I wish I had looked better, but it was so damn cold I didn't care too much.
I basically fixed the problem by a lucky stroke, but my friend (the owner of the car) thinks I'm a genious, so I'll leave it like that!
Thanks for the comments.
GOOD FOR YOU. IF YOU'RE A HERO THAT'S ALL THAT MATTERS.
NOBODY BUT US WANNA BEES WILL KNOW YOUR SECRET
Hello, I'm new here. I came accross this site and this Idle issue, because I have had this exact same problem for two weeks now, driving with one foot on the brake and one on the gas when I come to lights and stop signs. Well, the temperature here in CT has now risen above the freezing mark, actually, we've been from -10 to +15 for two weeks now. Low and behold, the problem went away. I am sure everything you suggested here is what I need to do, as for cleaning and checking things, however, I too unplugged the MAF and found the symtoms to go away. Now that it has warmed up to a balmy 25 degrees, the engine is running fine, even with the MAF plugged in. Bottom line, I don't think the contour likes the air temp below 15 degrees, when the rest of the system is most likely not running at optimum. By the way, I am driving a 95 with the V6.
Welcome onboard.
Yes, you can almost tell the weather outside (at least in the NE) by the types of problems posted in this forum. Going sub-zero tonight so our Contique cold-weather problems may return in the morning.