idle idle idle idle idle idle (dead)

[nocolourblue]

hello all,

i'm having idle/stall issues with my 96 sc1 auto 148k. All of a sudden, upon starting the car, using my usual muscle memory, it immediately stalled. restart, had to press accellerator and finally turned over again, but stalled immediately again. attempt 3, held down accellerator to keep rpm's where they would usually be, slowly letting off the gas to see where the needle lands, and it drops along with me letting off the gas to the point of 300 all the way to 100 rpm, and then stall when putting into reverse.

days later...

problem consistant with cold starting... once temp needle makes its way to almost the 1/4 mark (pressing accellerator to keep her rpm's where they should be for the warm-up process), the problem goes away completely and she runs perfectly like she has for so many years.


not sure where to go from here... i've cleaned tb, iac (not removing, just toothbrush, etc..), egr looked fine, pintle was fine,(cleaned it les than two months ago) but the gasket was a little rough around the edges.

my theory is ects.. but i dispute my own theory because saturn replaced it less than two years ago..and the connector.

this brings me to my question and my plea for advice.. what is the lifespan of an ects? it is possible that this is the culprit? can an ects look ok, and still be faulty? (haven't checked it yet) being that the car performs beautifully once warmed up, i just don't know how to proceed.

once again, i submit to you all, and i hope there is some help out there. like always.

[nocolourblue]

oh, also, it threw the low idle code (506 maybe? not sure of the number anymore, but the info only says low idle... which i knew )

[madpogue]

Question (singular)? Um, that's THREE questions?

Originally Posted by nocolourblue

this brings me to my question and my plea for advice.. what is the lifespan of an ects?

Lifespan - Original (plastic-tipped), don't speculate on it, just replace it. Brass - should last the life of the car.

it is possible that this is the culprit?

Yeah, possible. Presuming it's the '96 in your profile, how does the temp gauge read? That could be a clue. Also check how they installed the new connector; make sure the connections to the original wires are still good.

can an ects look ok, and still be faulty?

Plastic-tip - fault should be evident (physical crack). Brass - there have been scattered reports of AFTERMARKET brass-tip sensors being bogeys. There would be no outward sign. But that's aftermarket; I don't know of any failures of OEM brass ECTS. Still, if it were to fail, since it's brass-tipped, indeed it would probably look fine.

[nocolourblue]

indeed it was three. heh.. oops!

it was replaced by saturn two years ago, so i can only assume it's brass.

temp gauge reads at the 1/4 mark and pretty much stays there once the car is warmed up. it did, however, fluctuate one way and then the other a few ticks rather rapidly for about 30 seconds the other day while i was waiting in a drive-thru. i have never seen it do that before. seemed like my dash lights were dimming along with the fluctuation.


i'll pull the ects tomorrow and look at it, but i'm feeling like that's not it anymore.


What can one do to an IAC other than spraying some stuff in it when cleaning the TB? IAC is my next target.


thanks!

[madpogue]

Well, with that vintage of car, the gauge should read higher (3/8 or so). Don't bother removing the ECTS. Just look at http://www.saturnfans.com/photos/sho...4/si/newer.jpg , (see the difference in the part that's visible from the outside?), just to verify that the installed sensor is indeed the brass one.

Gauge reading might be low because the thermostat is stuck open. How's the heat?

You can remove the throttle body, and clean out passages (including the IAC passage) that you otherwise couldn't reach. That would be my other suspect.

[GreenSC2]

Originally Posted by nocolourblue

it was replaced by saturn two years ago, so i can only assume it's brass.

Don't assume anything.... No need to pull it just look at it in the car and compare it to the picture:

[nocolourblue]

Originally Posted by madpogue

Well, with that vintage of car, the gauge should read higher (3/8 or so). Don't bother removing the ECTS. Just look at http://www.saturnfans.com/photos/sho...4/si/newer.jpg , (see the difference in the part that's visible from the outside?), just to verify that the installed sensor is indeed the brass one.

Gauge reading might be low because the thermostat is stuck open. How's the heat?

You can remove the throttle body, and clean out passages (including the IAC passage) that you otherwise couldn't reach. That would be my other suspect.

the car has always run at 1/4. i've had it for 6 years and it has never gone above 1/4 under normal operating conditions.. sure it goes up if i'm sitting in traffic forever, but i don't consider 1/4 to be abnormal or low at all since it has been that way for the duration of my ownership.

i'm all for removing the tb and cleaning out the iac.... but my larger question is.. what difference would cleaning out these parts make if the problem only exists when the car is cold? again, once warmed up, the car operates perfectly..


i'll have a look at the visible part of the ects tomorrow. thanks so much.

[harsha]

Just a thought here.... How's the fuel filter doing?? Was it replaced recently?? This might/might not pertain to the solution..... Worth checking it!! I still feel it's something related to fuel flow?

[nocolourblue]

Originally Posted by harsha

Just a thought here.... How's the fuel filter doing?? Was it replaced recently?? This might/might not pertain to the solution..... Worth checking it!! I still feel it's something related to fuel flow?

fuel filter, to my knowledge, has never been replaced. i personally have never had it done, and i doubt the previous owner did, as the car only had 68k when i got it. i should change it eventually, but in all my forum searching, i haven't found a fuel filter to cause that particular code to throw my ses light.

will a fuel filter know whether or not a car is warm? i'm really trying to narrow down what would be a problem cold, and not be a problem hot.

thank you !

[paulo]

Temperature gauge rapid movement- CTS/wire connection
Physically check CTS/spray wire connector with PB Blaster
If problem persists push down on CTS cap with motor running, if idle changes-bad connector.

[nocolourblue]

ok. i'll check that tomorrow along with which ects i have... although if saturn put the old style ects in two years ago... i'll be thoroughly disappointed.

[BarnOwl]

Originally Posted by nocolourblue

the car has always run at 1/4. i've had it for 6 years and it has never gone above 1/4 under normal operating conditions.. sure it goes up if i'm sitting in traffic forever, but i don't consider 1/4 to be abnormal or low at all since it has been that way for the duration of my ownership.

Have you ever replaced the thermostat? My '96 acted just the way you are describing. One day I was changing my coolant and decided I might as well change the thermostat while I was at it. I pulled the thermostat housing and guess what. I didn't have a thermostat at all. I put one in and it ran at 3/8.

[harsha]

Originally Posted by nocolourblue

fuel filter, to my knowledge, has never been replaced. i personally have never had it done, and i doubt the previous owner did, as the car only had 68k when i got it. i should change it eventually, but in all my forum searching, i haven't found a fuel filter to cause that particular code to throw my ses light.

will a fuel filter know whether or not a car is warm? i'm really trying to narrow down what would be a problem cold, and not be a problem hot.

thank you !

The fuel filter itself doesn't have any sensor in it to send readings to PCM and throw faulty codes. But I was thinking when there's restriction when fuel gets to the injector from the fuel tank through fuel filter. If there's some corrosion or blockage in the filter?, there wont be enough pressure in the fuel system for the engine to run smoothly. So, as you described the problem, I was thinking some restrictions in fuel flow?? Just a thought here. What you can do is(I know that's not the right way), take a visiual look at the filter to determine it's age(if it looks like new or if it looks like it came with car from the assembly??)

[westwind999]

I doubt it's the fuel filter. If it gets clogged you loose power under load because it can't keep up with the fuel useage. The amount of fuel to start the car and keep it running is rather small and shouldn't be an issue for a clogged filter.

How about a crank position sensor, maybe has some crud on it that needs to be cleaned off or isn't working properly? They sometimes are intermittent.

Other than that start with the basics, compression, ignition, fuel pressure(maybe a failing pressure regulator?)

[nocolourblue]

ok, so it's definately the newer ects, and the connector appears to be fine. so i'm scratching that off the list. as far as the temperature goes, i'm not at all concerned about it running at 1/4. it's been at 1/4 for 6 problem free years. i was only demonstrating that 1/4 is what my car considers to be warmed up, and that 1/4 is where the new problems with the stalling goes away.

harsha, it's the original fuel filter which one day i'll get around to fooling with, but for the moment i don't think that's the issue. but i thank you for your thoughts on the matter.


an egr question.. the egr itself seems to be clean and operating normally. no sticking pintle. but if the holes on the engine side of the egr are still cruddy, would that make a difference? there is some buildup there, but the passages are super clogged or anything. if that might have something to do with it, how does one go about cleaning that without getting a million little carbon pieces inside the passages? (i don't hve access to any sort of suction device to assist me with cleaning this)

thanks for helping me narrow this down.

[nocolourblue]

so this morning i had a little time to play around with the TB and see if i could narrow this down some more.

idle still staying around the 150 - 250 area. it's actually staying there whether the car is warmed up or not now, i.e. warm car no longer returns idle to normal.

thought i'd try something, so i unplugged the IAC.

started car.. same problem.. 150 rpm at idle

is my iac broken?

what are your thoughts?

[nocolourblue]

a little bump never hurt

[BarnOwl]

Did you take the throttle body off the car to clean it? If you've never done it, you probably should try that. You'll be shocked at how crudied up it gets.

[nocolourblue]

i did finally remove the tb and cleaned it. it was pretty gross on the other side. and i removed the IAC and was shocked to see as much gunk in the spring as there was. so i cleaned all that out and bingo, car ran perfect for about a week. not idle issues at all. but it's doing it again. car will not stay on by itself because the idle is so low (throwing it in neutral and giving gas at red lights, etc...) . i have until the end of this month to pass emissions and i will surely fail with the car acting like this.

replaced egr gasket. longshot...didn't help.

could an iac be fixed due to gunk and then just... die?

or am i looking at a new egr? is there a way to test and egr by itself?

thanks guys... been a while since i posted in this thread, but i'm still haunted by this problem.

[SaturnManiac]

If you know someone with a car similiar to yours, borrow their IAC to see if that's the problem...it's always good to be able to test things that way with a known good device.