So, I have an intermittent rough idle. It will idle fine for a few seconds, then it almost sounds like it has a cam in it, like.............blub, blub, blub...................blub, blub..............I've already put new plugs in, that didn't help...gapped them tighter (.035) and it still does it. I recently had a stage 2 put on and a new fuel filter.....it did it before I put that stuff on and none of that changed anything, so I don't think it's a fuel problem. I checked for vacuum leaks and didn't find any....replaced a hose that was rough looking. I also tried cleaning the throttle body and MAF......didn't help. I'm thinking it might be one of the coil packs? I've never gotten any cel's though. Any suggestions?...this is driving me crazy....especially when I'm sitting in traffic in a car with only 45k on it, and it's idling like a piece of junk. The spark plugs I am using are Champion 7546's....it's a double platinum plug.....could these plugs be causing a problem?

 

Check again for vacuum leaks. Mine sounded like it was cammed and idled like **** when I had a vacuum leak because my intake mani wasn't bolted down all the way.

 

my friend with a SC and gms2 sounds like that whenever he idles with his AC on

 

i have an lnf and mine does this, intermittently as well. I've replace front o2, purge valve, plugs, checked hoses for vacuum/boost leak. I cannot figure it out either, it doesn't hurt me performance wise, just sounds funny.

 

I'm gonna go to autozone today and see if any codes are popping....if it's a misfire it should be logged.....I've never had the mani off, but that's still a possiblity...I might just replace the intake gasket.

 

mine LNF does it from time to time, usually a few revs to 2500 or so clears it up.... or turning it off then back on. i think its the ecu wigging out and dumping too much fuel

 

Most of the time with the stage 2 and up it will do this what you need to do is pull the throttlebody off and clean with tb cleaner then spray some on a rag and clean the supercharger inlet. Mine was doing the same thing and this fixed it.

 

Mine is fine if I rev it, but goes right back to idling rough. I hope it's not something major.

 

I already tried cleaning the throttlebody....from what I understand that fix is to stop the surging idle....mine sounds more like a misfire.

 

my guess is dirty/sticking injector.

 

injectors were replaced with stage 2

 

Mine is still stock and sounds like this, I also get backfires when shifting from 2nd to 3rd and 4th to 5th.
Car has no codes and all looks good on hptuners.
Car also runs different from day to day, some days like a scalded dog, some days like a fat lazy pig...

 

when i went 2.8 & 60s it would idle like it had a mild cam

my AEM wideband gauge reads at idle from rich to lean, from rich to lean
when it leans out it reads(- --) its cammed but went the gauge reads(12.0-14.7)

seeing how im not on the throttle its not an accurate read.....all the AEM widebands on lsj's do this

on the throttle (cruising) its at (14.4-15.0) inbetween and at WOT its in the 11's

i think it sounds cool haha at idle plus with the solid mounts

 

Well, I decided to seafoam the engine via the vacuum line. When I fill up tonight, I'll dump the rest of the bottle (2/3's) in the gas tank. It didn't blow out all that much black smoke, but I noticed the tail pipe is all sooty now. It did seem to help the idle some, I can still hear it if I listen by the tailpipe though. Only time will tell.

 

My SS/SC did this with 5000 miles on it when i added stage 2 . It had an idle misfire that was very random and would never throw a code .... I had to use a tech 2 to graph it or something simular . My idle would be like errrmmmmmmrmmm puft errrrrrrrrm puft puft errrrrmmmmm puft. My friend was the service manager at the local dealership and we replaced the coil packs , timing chain tensioner , injectors and plugs . I think its just the way the GM tune is.

My car idled just like this .... I know its a redline but same difference

YouTube - 2007 Saturn Ion Redline Exhaust--Dezod 2.75" w/Magnaflow #1

 

That's EXACTLY how my car sounds. My car has always done it though, even before stg 2.Seeing that you replaced all that stuff and it didn't help, I'm not going to waste my money then. . Not sure what can be done about it, if anything. I might try and swap my plugs again...this time to iridium's since those are what's suppose to be installed on it from the factory on 07's. They might have lower resistance or something.

 

In most cases it's normal to idle like this, what you could do is compare your CKP to CMP on the intake to see what it's doing at idle, it shouldn't have much varience but if it does the next thing is to compare how far out it actually is, and the end result could be timing chain replacement. Otherwise, all is well.

 

How would I do that? I already replaced the tensioner to the new style, and rarely, like once every 100 starts I can hear a rattle in the vicinity of the timing chain, a quick small rev makes it go away. I went ahead and changed my plugs to the OE iridium's. It made absolutely no difference in the idle. Since they are lower resistance than platinum, I thought maybe at idle, when voltage is lowest that it would help. Waste of money...lol. How hard is it to change the timing chain on these cars?

 

The actual resistance is in the gap and spark load increases with engine load, so at idle, if your having perceived spark issues, but it drives fine, it is not your ignition system.

Your dealer/tech/friend with a good scan tool checks to compare those two values, the book says 2-3 degrees if fine for most cars. What COULD be happening is a dirty injector flowing poorly and causing fuel to pool and thus misfire at idle.

 

I don't think it's the injectors because I just had a stg 2 kit put in it, and it made no difference.....idle is exactly the same as it was with original injectors. Don't know anyone with a scan tool, but maybe I'll take it to the dealer sometime and have them check it out.....how much would a good scan tool like that cost?

 

mine does it to radomly it have no clue y tho

 

If i turned my AC on it would smooth out the idle on my SS/sc .