15 replies to this topic

[T5power]

so last thursday aaron gave me a hand replacing the SS brake lines, oil change, spark plugs and tie rods. that friday, i decided to do seafoam treatment through the intake mani. prior to this i had idled perfectly fine. but now whenever i start the car it will idle funny. even when i'm driving around, it will dip down to about 500RPM occasionally, and will make the car shake. i figured it would go away once i finished the seafoam procedure, but that was last week.

i also had a CEL for 0172 prior to this. vacuum leak. i know where it is. it's the elbow on the passenger side of the intake manifold. i bought the PCV kit to replace this today.

any help?

Edited by Goldmember, 29 September 2010 - 11:54 PM.

[ohsleeper]

moar seafoam

[flyfishing3]

vapor lock?

[T5power]

i should also mention that this is not ALL the time. it will idle like this maybe 25-30 percent of the number of times i am at idle. absolutely no hesitation at higher RPM's whatsoever

[Keep Calm Chive On]

brakes run off vac make sure youve properly bled the brakes. Also, did you clean your IAC? & TB? When i seafoam i do the following.

Clean MAF,
Clean Throttle Body
Clean IAC
Clean Hoses
Check for leaks
Seafoam through intake (1/4 of the can)
Check all Vac lines for TCV
Make sure PTC is legitskis still & cleaned as best it can
Throttle tight with no slack.
Usually Plugs as I do it right before an oil change (dont put it in my oil)

I have a beautiful idle at 850rpm.

It does occasionally fluctuate but that is because when fan turns on it dips or anything along those lines.

Is it like BOGGing out?

Could be some shit on the plugs. SEAFOAM itself is safe for cats, the shit it breaks up not so much ahha

[Reximus]

so last thursday aaron gave me a hand replacing the SS brake lines, oil change, spark plugs and tie rods. that friday, i decided to do seafoam treatment through the intake mani. prior to this i had idled perfectly fine. but now whenever i start the car it will idle funny. even when i'm driving around, it will dip down to about 500RPM occasionally, and will make the car shake. i figured it would go away once i finished the seafoam procedure, but that was last week.

i also had a CEL for 0172 prior to this. vacuum leak. i know where it is. it's the elbow on the passenger side of the intake manifold. i bought the PCV kit to replace this today.

any help?

explain more about the dip down of RPM... what happens if you gave it a little bit of gas just enough to raise the RPM above 800? will it run smooth after that? or will it still shake a bit?

[T5power]

Runs completely fine if I just goose it a little bit. Like I said it's only part of the time. I'll inspect the plugs and report my findings soon.

Do you REALLY think adding more seafoam will help? I'm not sure if you're kidding or serious

[Reximus]

Runs completely fine if I just goose it a little bit. Like I said it's only part of the time. I'll inspect the plugs and report my findings soon.

Do you REALLY think adding more seafoam will help? I'm not sure if you're kidding or serious

did you put seafoam on the maf sensor by the way? also P0172 is "system too rich bank 1", a small vacuum leak wouldn't cause it to run rich, would be lean if anything. or sometimes a misfire perhaps. but if you have a known vacuum leak somewhere, please do fix it... rough idle, goes away with raised rpm, is usually the symptom of vacuum leak. listen for a hissing noise when it happens if possible... once everything is in good working order, wait to see if the p0172 would come back or not... good luck

[T5power]

did you put seafoam on the maf sensor by the way? also P0172 is "system too rich bank 1", a small vacuum leak wouldn't cause it to run rich, would be lean if anything. or sometimes a misfire perhaps. but if you have a known vacuum leak somewhere, please do fix it... rough idle, goes away with raised rpm, is usually the symptom of vacuum leak. listen for a hissing noise when it happens if possible... once everything is in good working order, wait to see if the p0172 would come back or not... good luck

Nope. I fed the liquid through the boost gauge line directly into the manifold. I will definitely do what you said. Great advice thank you

[--Aaron--]

Let's get a fresh PCV on and fix that leak in the process. I almost guarantee you the problem will go away. Personally, I wouldn't touch anything else until the PCV job is done. One thing at a time grasshopper.

[T5power]

Let's get a fresh PCV on and fix that leak in the process. I almost guarantee you the problem will go away. Personally, I wouldn't touch anything else until the PCV job is done. One thing at a time grasshopper.

yeah true. I just got your text about an hour ago.. I don't think I got it at the right time lol cause the time was wayyyy off.... When did you send that??

[--Aaron--]

haha monday morning i think lol but yeah man lets fix what we know is wrong and see if the issue disappears, im pretty damn sure it will

did you get a new pcv kit? brands of parts?

also kurt, are u drunk? why the monkey would a motor idle stupid if the brakes werent bled properly LOL i dont think u read what you type man

and no im not drunk im at work

[Keep Calm Chive On]

i do read what i type but what my point was there is a brake booster which takes vacuum... if your brakes arent bled properly (seeing as most people have a foot ont he brake when stopped... sorta like how a 5 speed rolls with the clutch in unless you have figured out a way to idle with the clutch out in gear). This would require more vacuum to the booster to supply the same amount of braking force an create harder braking. its not nessisarrly that but when many small things add up it tends to create an strain on the motor seeing as its considered a VAC leak which we all know can cause idle, boost, & lean/rich conditions... say your fan kicks on, your AC kicks on, you have a slight leak in the brake booster or perhaps even a bad master cylinder... now they all happen at once this is an instant increase in load to the motor which will yes make an RPM dip. everyone knows when i fan kicks on you can see a ~50prm drop occasionally and thats 1 item... now add in a few more... its still a vacuum leak

that clear it up for ya? im not saying its the problem im not saying it has happened im not even saying that i guarantee that its an issue but it IS a vacuum leak when this happens (the brake booster thing i was "wrong" on) so just like any other vacuum leak it can case the same symptoms as a cracked hose somewhere else...

tell me im wrong then go rip your brake booster vac line off...

i was simply giving him other options but seeing as he basically answered his post in his post... thats kinda a given...

[NEU]

vapor lock?

Mike your are truly showing your age...

[--Aaron--]

i do read what i type but what my point was there is a brake booster which takes vacuum... if your brakes arent bled properly (seeing as most people have a foot ont he brake when stopped... sorta like how a 5 speed rolls with the clutch in unless you have figured out a way to idle with the clutch out in gear). This would require more vacuum to the booster to supply the same amount of braking force an create harder braking. its not nessisarrly that but when many small things add up it tends to create an strain on the motor seeing as its considered a VAC leak which we all know can cause idle, boost, & lean/rich conditions... say your fan kicks on, your AC kicks on, you have a slight leak in the brake booster or perhaps even a bad master cylinder... now they all happen at once this is an instant increase in load to the motor which will yes make an RPM dip. everyone knows when i fan kicks on you can see a ~50prm drop occasionally and thats 1 item... now add in a few more... its still a vacuum leak

that clear it up for ya? im not saying its the problem im not saying it has happened im not even saying that i guarantee that its an issue but it IS a vacuum leak when this happens (the brake booster thing i was "wrong" on) so just like any other vacuum leak it can case the same symptoms as a cracked hose somewhere else...

tell me im wrong then go rip your brake booster vac line off...

i was simply giving him other options but seeing as he basically answered his post in his post... thats kinda a given...

You are thinking too much, air in the brake lines is not going to affect idle speed.

If it makes sense to you though rock on.

Pulling any vacuum line off is obviously going to cause a vacuum leak, similar to the one Corey has, which I felt with my very own hand. Now that is something that can affect a motor's idle. I do not need to pull one of my vacuum lines off to prove something that is obvious.

[Keep Calm Chive On]

In no way would i say that because theres an air pocket in the line you have a bad idle. but if stress adds up & a dry rotted brake booster line takes a poop...

Pulling any vacuum line off is obviously going to cause a vacuum leak, similar to the one Corey has, which I felt with my very own hand. Now that is something that can affect a motor's idle. I do not need to pull one of my vacuum lines off to prove something that is obvious.

we all know this thank you...

stress on brake (from improper bleeding) can cause dry rotted brake booster VACUUM line to become el shitto

Like i said before... he answered his post in his post before ANYONE could have told him otherwise. All im doing is telling him (and everyone) in general of other possibilities of "little" things similar to the little vac elbow on the side of the intake manifold that tend to cause such "large" issues. If your not interested, your not interested and quite frankly i dont care... im simply trying to give someone some possibly helpful information so that one day the "rough idle" thread doesnt brew into "vac leak" thread to "not the intake elbow" thread" to the "wtf cant find the leak" thread... its just a thought. When you work on something (ANYTHING) you tend to check all related parts, or at least thats what im fond of.

Im sorry my information didnt blow your mind to the point you had to change shorts, its still information