freaknbigpanda

Hey Guys,

When my car idles the RPM does not stay constant it changes by about 50 every few seconds, going up and down very slightly. When this happens I also feel a little bit of a shake through the seat.

Is this behavior normal? And if it isn't what should I look for?

Thanks!

SonnyAK

My '09 is smooth and consistent at idle. It's completely stock. Any mods on yours?

digitalmike

Mine is 09 as well and it also idle rough same as your car and i was wondering same exact thing. If thats normal or something is wrong with it. Hopefully we will get some idea of whats wrong.

1972bluelt1

Probably has nothing to do with it, but my 07 idled a little rough for a few seconds after a clod start up. I used CRC mass air flow cleaner on the MAF sensor and so far so good, it hasn't done it since.

Landru

Have any code(s) been set?
If you've no OBDII reader go to any parts store, they'll check codes for free.

Absent codes, I agree w/ above.
Sounds like it may be a MAF issue.

Bad00SS

mine did this when I bought it and i put new spark plugs in. it had the original plugs and the car has 50k miles. its better now.

geno01

I would check your air filter also.

freaknbigpanda

So I just attempted to clean my MAF. Basically I took it out and sprayed both the metal plate side and the plastic side with a bunch of MAF cleaner. I also sprayed the throttle body with throttle body cleaner and it seems my idle is exactly the same as before... what should I check next? The spark plugs? Or maybe I didn't clean the MAF properly? All I did was spray it several times with the cleaner.

1972bluelt1

I guess I'd start with spark plugs. Hate to just throw parts at a problem, but a MAF is only about $50. Once bought $600 one on the advice of service tech. Turned out to be a $16 pair of relays.

redbird555

Every ls car I've had had a shake or hitter at idle. Nature of the beast. Unless it's an actual noticeable misfire I wouldn't touch it. Most likely you're chasing a phantom

freaknbigpanda

this isnt may car but this is exactly what it looks like:

https://youtu.be/nmCArolKXVc

is this normal?

Landru

IF cleaner was used properly, probably isn't a dirty MAF.
However since MAF was completely removed to clean, make damned certain it was replaced properly orientated, not backwards.

Surprised how many capable people made this mistake over the years.
It's apparently all too easy to do, so recheck your work & go from there.

freaknbigpanda

i put it in with the metal plate facing up, this is the correct orientation right?

1972bluelt1

2 LS1s, an LS7 and an L98. All idle a bit rough. More than our GMC Terain or my truck.

MTPZ06

I'm not sure the bolt pattern allows it to be installed incorrectly, but its been years since I pulled mine.

Even though it may not be MAF related, I would say check to make sure you don't have a "weak MAF" model. I recall checking mine and was in the clear... https://www.corvetteforum.com/forums...light=weak+maf

Landru

IIRC there's an arrow by connector, tho' have never messed w/ MAFs on either my '06 or '08, other than look at it while changing air filter.

Do a search using, 'MAF in backwards', turns lots of hits.
After, sifting tossing postings from the 5 previous generations.
I swear more than one member getting this wrong, supposedly very easy to do, causing weird idle etc.

One always assumes they did it properly, spend hours & sometimes $ before through pure desperation discover their mistake, and to a one they all felt stupid. I would've too, self inflicted wounds hurt the most.

Check orientation, if it's correct it ain't MAF & it's off to the next step.

freaknbigpanda

Can you guys check out the video and let me know if this is normal or not?


This is what my car is doing, if this is normal I'm just going to ignore it. I just don't remember it at all in my last corvette but maybe I just missed it.

ssbowtie1

I wouldn't say that's normal, but unfortunately you can tear down your whole car trying to chase something like this. If it was me, I would do a full tuneup, change all filters and fluids, clean the maf and see what happens.

Tech

Looks normal to me.

Bad00SS

mine was worse than that even. spark plugs fixed it.