idle control

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jokken

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hey everyone.

dont get on this forum anywhere near as often as id like

only when I have issues I come on to ask about
any ideas about this?:

for a few months now I have noticed on my 2000 LS v6 3.0L 5spd manual the idle seems wacky.

Often when I come to a stop the car stays at whatever RPM it was at last as I stopped downshifting and kept the clutch pressed in (used the brakes to stop the rest of the way). This also happens if I leave the clutch out and the trans in neutral (used the brakes to stop the rest of the way)

another strange idle characteristic is that often but not always, when in neutral idling the idle will dip down below 1000 and then bump back up. back and forth.

the first thing that comes to mind would be an idle air control value. but that is just something I've replaced on another car I had a long time ago. does this LS even have that?

any ideas what is causing this? thanks
 
thanks joegr. I am looking to buy that part now. i'll let you know how it works. but i trust it'll fix the problem. thanks!
 
Mine did that when the PCV hose cracked. Replacing it fixed the erratic(ish) idle.
 
I hate to say it joegr but changing the IAC aka Idle Air Bypass Valve didn't fix the erratic idle issue. :(
i didn't buy the motorcraft one but the brand I used seemed fine.
it was like this one:
rockauto

but now I am seeing a new, potentially related, but possibly unrelated, problem.
The engine often, but not always, bucks and stutters under moderate to heavy acceleration, say 3k to 5k rpm. With slow and gradual acceleration it hardly ever happens.

my first fear was that it is the valve cover gaskets and there is oil in the spark plug wells again. but I did change these gaskets already, although it was probably 60k ago. but also I pulled the drivers side 3 coils and found no leaks (other 3 coils are under the intake manifold) and there is also no CEL (I have not checked for codes yet, but i could, i have an OBDII scanner.)

this is 2000 LS v6 3.0L 5spd manual with 121k

any ideas?

msgtusmc, thanks, the TPS seems a logical answer, at least for the initial prolem, where is that located on my car?

ls4me, thanks, I'll check for cracked hoses but i don't think my 6cyl has a PCV. At least from what I remember. Is that true?
 
Sorry about it not being the IAC. Your comment about it staying at certain RPMs certainly sounded like an IAC issue.

My best guesses now about the new symptoms are that (1) you probably need new coils and plugs, and (2) your PCV plumbing may be failing.

Coils can fail or become marginal with no exposure to oil. None of the ones that have failed on my two LSes were ever exposed to oil or water.

All years of the LS, V6 and V8 have PCV systems. The V8 does not have a PCV valve, but your V6 does.

The TPS is on the side of the throttle body.
 
no worries about it not being the IAC. cheap enough part, super easy to change, and it was never changed before anyway so... i'm probably better off.

oh... so I'll have to change the PCV and plumbing and check out the TPS too

thanks again guys!
 
oh and also,
i changed all the coils when I did the valve cover gaskets, 60k ago, just for thoroughness sake. but I hear you that it still may be the coils again. I'll play around with the PCV system first since it has never been changed and then I'll do the coils and/or tps

come to think of it... when I had the driver's side 3 coils out and put them back in the car did seem to run better for a day...
 
jokken said:
no worries about it not being the IAC. cheap enough part, super easy to change, and it was never changed before anyway so... i'm probably better off.

oh... so I'll have to change the PCV and plumbing and check out the TPS too

thanks again guys!
Click to expand...

Like I said earlier; my exact symptoms caused by the cracked PCV elbow. I also tried the IAC first with little success.
 
thanks joegr and LS4me.

NYCLS8 thanks for the directions and pictures. very helpful.

I finally got to taking this apart, I am at the point now, I think, that I need to take the spacer block under the intake manifild off (I'm not seeing a pcv yet). But before I take off the spacer block I want to be sure that I need to first take off the fuel rail right?

things do a look a little different on my 2000 LS V6(5spd) than your 3.0 JAG. We are sure that the fuel rail, spacer block and pcv is the same right? no offense :)

here is a pic of where I am:

nointake.jpg

http://www.jokken.com/downloads/nointake.jpg

thanks!
 
jokken said:
thanks joegr and LS4me.

NYCLS8 thanks for the directions and pictures. very helpful.

I finally got to taking this apart, I am at the point now, I think, that I need to take the spacer block under the intake manifild off (I'm not seeing a pcv yet). But before I take off the spacer block I want to be sure that I need to first take off the fuel rail right?

things do a look a little different on my 2000 LS V6(5spd) than your 3.0 JAG. We are sure that the fuel rail, spacer block and pcv is the same right? no offense :)

here is a pic of where I am:

nointake.jpg

http://www.jokken.com/downloads/nointake.jpg

thanks!
Click to expand...

I believe it's under the lower intake. I believe that is what you call a spacer.
 
ugh, now that I see the date on my last post i see that my LS has been apart in my driveway, not running, for almost a month. saturday i finally got to taking this apart more.

i've got more questions. sorry, please bear with me...

i got the lower intake off and found the PCV value. seeing it I remembered something from the past. can you believe I think I once changed this PCV valve years ago without taking off the lower intake. With the upper manifold off and all the wires pushed back I got a deepwell socket in there and twisted it out and twisted the new one back in. the socket was just the right size to fit around the square part (4 points) of the pcv valve... (maybe it was on my brother's sport trac explorer but i really think it was on this car)

maybe it was a miricale. here's a pic of the pcv valve for an idea of the square part
pcv.jpg


anyway...

my pcv valve hose elbow wasn't cracked but it had collapsed alot. I hope this is the issue. air flows freely through it until I squeeze it a little, collapsing it more.

see pics: (sorry they are burry)

ls1.jpg

ls2.jpg



what do you guys think, is this probably the problem?

now I need torque specs to put this back together. I went and bought a 1/4" torque wrench just for this job.


I also have a few more questions. here is a part diagrams:
(for people's FYI part # 6767 is the collapsed pcv valve hose elbow.

ls3.jpg

can part # 6A785 be taken out without removing the heads? i wanted to see down there, but can't get it out from between the lips of the intake holes in the heads..

part # 6A664 is the rest of the PCV valve hose. can this just be replaced by like a 1/2" hose? or is this something special? (is this something I am reading about an Emission Separator?)

thanks guys!!!! I am trying to ask a few questions and also provide info for others who come across this issue. NYCLS8's directions and pictures in the excel sheet was the most helpful (especially tab # 7. urg i didn't see tab # 7 until I opened it on a different computer, ish - go figure, now it make more sense!!!
 
Last edited:
I don't know about the other stuff, but that PCV hose has failed! IIRC that hose is under vacuum and when the engine is running the hose will collapse even further.
 
LS4me said:
I don't know about the other stuff, but that PCV hose has failed! IIRC that hose is under vacuum and when the engine is running the hose will collapse even further.
Click to expand...

ah thanks LS4me. that is what i was hoping someone would say. I was a little upset when I didn't see any cracks or holes in it. i will replace it saturday and put it all back together...


yeah!! my new second car is a 03 deville. it is nice but i do miss my LS, rear wheel drive and the manual.... so can't wait to be back on the road with the LS!
 
sadly I just got this all the way back together. delay was because of lack of motivation, plus lack of time, plus all the connectors on the fuel injector wires cracked (were too brittle) when I had taken them off. I had to splice/solder new connectors on all 6 (12 wires). boy I hope I did that right.

The last thing I did was tighten the 3 COPs on the drivers side and found all 3 spark plug wells were filled with antifreeze! not oil, antifreeze.

what could this be!? please advise...

i sure hope this isn't a blown head gasket. the oil seems clean not milky, all black.

I had been having an issue with coolant. the doofus container was cacked and the car over heated a number of times, spraying antifreeze everywhere. once that was fixed I had the coolant flushed. The very next day (just my luck) a radiator hose blew and spayed antifreeze everwhere again.

i read someone on this forum this could be near the coolant sensor. and if it is bad coolant might be coming in through it.

thanks guys!
 
I don't see anyway that a headgasket issue would leave coolant in the plug wells. I would say that it sprayed there from a leak somewhere.
 
joegr said:
I don't see anyway that a headgasket issue would leave coolant in the plug wells. I would say that it sprayed there from a leak somewhere.
Click to expand...

Especially since you've had at least two instances of "sprayed coolant".
 
wheww!!! im gald to hear that. I cleaned them out and i'll check for more coolant in a few days. thanks guys

the car started up pretty easy, once i remembered to push the clutch in. lol!

it still isn't running very well. I think i have a failing COP in addition. I guess I SHOULD have ordered those 6 I had in my cart on rockauto. drag...

a CEL light came on on the third start, I think it was p1401. P1401 Differential Pressure Feedback Electronic Sensor circuit High Voltage

which doesn't suggest a misfire, maybe I've missed a plug or a hose. maybe I am not remembering what the code was.


edit: ohhh, the DPFE. that's what I am reading about p1401 in other threads. i had some issues putting that on. maybe I didn't plug it in.
 
ok, I ordered 6 of the Visteon 60-1004 Ignition Coils on ebay (this is a 3.0 6cyl). but I am already wondering what else the problem could be. not that I doubt some of the coils are bad, im worried is all, i feel there might be more wrong. The P1401 went away when I plugged in the DPFE (duh! jim!).

i did after all just splice 12 fuel injectors wires and have it all apart. so i'm skeptical, although i usually do pretty solid repairs

i guess i can use the stethoscope method the hear each injector spraying.

the car runs really bad, slow to rev when pressing the pedal

and for what it's worth:
exhaust sounds louder but weaker, like a small engine. and you can hear stutter in it. it also smells different. not like fuel or oil or coolant or eggs. i don't know how to describe it but I guess I'd just say a steamy smell. it isn't white and neither is the oil.

I wish a CEL/code would occur and tell me what cylinders are misfiring.

engine runs ok at idle but i can tell there is a miss and then when driving the miss is constant although better with speed. I don't see or hear a vacuum leak.

the car has been sitting off with a dead battery for at least 3 months

any other ideas? i guess i'll just wait to be able to replace the coils...
 
You must replace the spark plugs at the same time as the coils.

Check and see if your catalytic converters are getting hotter than normal. If so, it is raw fuel from the misfires burning off in the converters. It won't take too long to ruin them.

I've broken the locking tabs on fuel injector connectors before (not on the LS yet). I just used a zip tie to secure the connector to the injector. I never had a problem with that as a repair. I hope you soldered the splices.
 
thanks joegr, ill check the cats

i did try the zip tie method too, on one of them. and when I tightened the zip tie the connector just cracked more... lol
yes, I did solder the injector wire connectors thanks. (would be funny if I said I just used wire nuts?) * * * *:) i used heat shrink tubing too, and ample electric tape.

i had just replaced the spark plugs with the whole pcv valve tear down. there is 1 mile on them now, autolites.
but I just bought 6 more cause I was thinking i should do them again to be safe since the 3 on the drivers side had the antifreeze sitting around them for months. i got autolite XP104 Iridium plugs.

btw: the exhaust doesn't smell like eggs either, at least not yet.

next question: assuming the passenger side (cyl#123) COPs and plugs are still OK is there anything wrong with changing only the drivers side (cyl#456) COPs and plugs (different brands) and driving the car to test it? (i will definitely change the passenger side to match but may not have time to pull the intake off - i am way too busy on Saturdays...)

thanks for the help I know I am more a user/abuser than a participant here...
 
the cats didnt seem to be too much hotter than Id expect.

well, I changed all the COPs and spark plugs (autolite XP104 Iridium plugs and Visteon 60-1004 COPs) and the car ran sooo much better. you think in the first place i woulda of taken your and everyones advice given so much on this forum. replace the COP and plugs EVERY opportunity that you get!!!

for a day it was fine, although I detect some infrequent misfire. then it started acting up again bad. at this point I think I'm at the same problems I started with. but at least now I have CEL codes.

i'll start a new thread with these codes and symptoms.
 
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