Do I really need a tune after only doing these mods?

[Runawayhacker]

I've recently added the VMAX CNC Spiraled Throttle Body to my car and I'm loving the difference. I already have a K&N CAI on there, so I'm sounding good and loving the little bump. However, I'm experiencing some idling issues. When idle, there will be short periods where the car visibly idles rougher.

I've asked the the dealership's opinion on the matter when i took it in for unrelated issues and they say that I am introducing too much air now and it is messing with my Air/Fuel mixture. I can see the logic in it, but both of my bolt ons are advertised as "no tune needed". Do I really need a tune to correct this or is the idle issue likely from something else? Are there any remedies aside form a tune like a stronger MAF?

Thanks guys!

[Birm]

No you do not.

[nyrfan]

As Birm said these mods do not need a tune. With that said the SS is not the smoothest running car and does run a bit rough. Also check to make sure you have a stong MAF (see below link), as the weak ones have been known to create a rough idle.

http://www.camaro5.com/forums/showthread.php?t=142125

[45thAnniversary2SS]

It's a 376 cubic inch engine so gonna shake a little at idle. Do you have LS3 or L99? Like he said, you should not need a tune with those mods.

Have you compared yours to another SS? A little shaking and rumbling is totally normal at idle.

BTW.. noticed you are on the fence about headers according to your sig. Don't hesitate, just do it. Best mod I've done. Then go ahead and get the tune anyways.

[Runawayhacker]

Thanks for the quick replies. I have the LS3 (2012 2SS) and am loving it. I'm very accustomed to the rumble of a V8. Normally, I would pass it off as just some awesome HP, but this is my 2nd Camaro (1st was also LS3) and it did not have this issue. At it's worst, the RPMs will bounce between 500 - 250 and the car will shake in the same manner as if it were about to stall out (but not THAT bad). The shaking comes in cycles on time as well... about 5 seconds of smooth, then shivers. I've checked my MAF and as far as i can tell, I have a strong one.

I have another thread going about this separate issue, but I noticed it after the dealership had to replace my defective EVAP sensor. I'm wondering if someone bumped something loose when doing the work. Unfortunately, this was also around the time I installed my TB, so I can't say for sure what may be causing it. I've cleaned my filter, my MAF is spotless, my TB is spotless, I've done the fuse pull... Short of checking the spark plugs, I'm out of ideas.

Do you think it worth it to go with a 3rd party MAF?

[Birm]

Originally Posted by Runawayhacker

Thanks for the quick replies. I have the LS3 (2012 2SS) and am loving it. I'm very accustomed to the rumble of a V8. Normally, I would pass it off as just some awesome HP, but this is my 2nd Camaro (1st was also LS3) and it did not have this issue. At it's worst, the RPMs will bounce between 500 - 250 and the car will shake in the same manner as if it were about to stall out (but not THAT bad). The shaking comes in cycles on time as well... about 5 seconds of smooth, then shivers. I've checked my MAF and as far as i can tell, I have a strong one.

I have another thread going about this separate issue, but I noticed it after the dealership had to replace my defective EVAP sensor. I'm wondering if someone bumped something loose when doing the work. Unfortunately, this was also around the time I installed my TB, so I can't say for sure what may be causing it. I've cleaned my filter, my MAF is spotless, my TB is spotless, I've done the fuse pull... Short of checking the spark plugs, I'm out of ideas.

Do you think it worth it to go with a 3rd party MAF?

Steer clear of 3rd Party MAF's (ie JET).

The rough(er) idle is nothing to really be alarmed about. You have changed the amount of air without changing the amount of fuel (AFR). It is not enough to justify a tune unless you just want more power and everything cleaned up, but if you are going to spend the money on one I would invest in headers first.

It could also be in the porting of the throttle body, if done to aggresively the blade might not be closing all the way to compensate at idle.

There is NO REASON at THIS TIME with THESE MODS that you would need a tune unless you wanted one. And if you are going to tune, make it worth your while and add headers.

Hope it helps.

[Runawayhacker]

Originally Posted by Birm

Steer clear of 3rd Party MAF's (ie JET).

The rough(er) idle is nothing to really be alarmed about. You have changed the amount of air without changing the amount of fuel (AFR). It is not enough to justify a tune unless you just want more power and everything cleaned up, but if you are going to spend the money on one I would invest in headers first.

You car can/will typically adjust its afr automatically (learn period) over time.

There is NO REASON at THIS TIME with THESE MODS that you would need a tune unless you wanted one. And if you are going to tune, make it worth your while and add headers.

Hope it helps.

It does help, thanks! Is there any way to reset the AFR value so I can "start new"? Otherwise, I would assume it would take quite a long time for it to adjust to the new values. Do we know if the learning span is capped at a certain time range? (ie; monthly, milage, etc?) or is it for the life of the car?

[Birm]

Originally Posted by Runawayhacker

It does help, thanks! Is there any way to reset the AFR value so I can "start new"? Otherwise, I would assume it would take quite a long time for it to adjust to the new values. Do we know if the learning span is capped at a certain time range? (ie; monthly, milage, etc?) or is it for the life of the car?

Some companies recommend a re-learn period of about 30 miles on their products (Vararam Power Wedge, some CAI's). Your ECU should adjust within reason hence why CAI's and TB's are typically plug and play not requiring a tune.

The idle, as long as driving/performance are not harmed is no cause for concern.

When you get headers, then tune it. Until then I wouldnt worry about it at all.

[1JEWLDSSRS]

I wouldn't worry about the rougher idle either, I have an L99 and did all these mods to it , along with the headers and exhaust and have read on this forum that these cars have the "LS shake", I kinda like it myself, feels like you have a mild cam in the engine.Don't worry, enjoyyour new found power and throttle response.

[Runawayhacker]

I'm really glad to have some reassurance here guys. I was going nuts thinking "I don't have enough HP to be shaking THIS bad".

Birm, I know you recommended getting headers first, then tuning, so would there be any effects of waiting in between to do so or would you recommend doing them about the same time?

[urr2slo]

K&N comes with an oiled filter, you may have some oil contamination on you MAF, check it, clean it with the correct electrical parts cleaner and see if that helps.

GM cars don't like oil residue from oiled air filters on there MAF sensor. Try that and see if it helps.

[45thAnniversary2SS]

Originally Posted by Runawayhacker

I'm really glad to have some reassurance here guys. I was going nuts thinking "I don't have enough HP to be shaking THIS bad".

Birm, I know you recommended getting headers first, then tuning, so would there be any effects of waiting in between to do so or would you recommend doing them about the same time?

You can wait. I just installed long tubes a few weeks ago but can't get it in for a tune until Oct 2nd. It will throw a CEL but you will be fine.

Just won't get all the power out of it until tuned.

[Bo White]

I had a ported tb and a rotofab intake on my LS3 for along time with the stock tune.

[Runawayhacker]

Originally Posted by urr2slo

K&N comes with an oiled filter, you may have some oil contamination on you MAF, check it, clean it with the correct electrical parts cleaner and see if that helps.

GM cars don't like oil residue from oiled air filters on there MAF sensor. Try that and see if it helps.

Yep. thought this was one of my issues causing the rough idle. It did have a few, small drops of oil on it, but she is super clean now (yes, used the cleaner made specifically for MAF)