Time for a tune-up?

[paulv7260]

A couple of issues:

1. When I start er up and rev there is a mild backfire, not loud but more distinct than a cough.

2. Decelerating then cruising at 1500 RPMS there seems to be a lot of lag and what I think are vibrations coming from the chassis.

3. Car runs smoothly but at idle the lope is noticeable especially under my seat. To be expected with the L99?

860 miles on her. Thoughts from the experts before I take her in? I'm also waiting for the clip to fix the A pillar pop-out problem (its on backorder). Think I can wait until then?

Thanks

Paul

[SSOOCH]

I don't think it needs a tune. Sounds like it has issues. Take it to the dealer asap!

[MONEY]

Originally Posted by SSOOCH

I don't think it needs a tune. Sounds like it has issues. Take it to the dealer asap!

[paulv7260]

Originally Posted by SSOOCH

I don't think it needs a tune. Sounds like it has issues. Take it to the dealer asap!

Originally Posted by MONEY

OK, thanks. Making the appointment for ASAP.

Paul

[1320junkie]

I think its fine..let us know the outcome please

[paulv7260]

Originally Posted by 1320junkie

I think its fine..let us know the outcome please

Will do ...

[CamaroSpike23]

Originally Posted by paulv7260

A couple of issues:

1. When I start er up and rev there is a mild backfire, not loud but more distinct than a cough.

2. Decelerating then cruising at 1500 RPMS there seems to be a lot of lag and what I think are vibrations coming from the chassis.

3. Car runs smoothly but at idle the lope is noticeable especially under my seat. To be expected with the L99?

860 miles on her. Thoughts from the experts before I take her in? I'm also waiting for the clip to fix the A pillar pop-out problem (its on backorder). Think I can wait until then?

Thanks

Paul

1. how soon after starting it up are you reving it? during startup the engine runs extra rich. reving soon after startup is liable to cause some backfiring as there is excess fuel not being burnt.

not to mention, reving it too soon after engine start is not a good idea to begin with as you are putting excess strain on the motor before the oil gets a chance to circulate thruout.

2. what gear are you in when you are cruising at 1500rpm? try down shifting a gear. then again, you are in the auto.... and when you are cruising, it most likely is switching to 4 cyl mode.

3. let her break in some more.

you can wait on the A-pillar. its cosmetic.

[paulv7260]

Originally Posted by CamaroSpike23

1. how soon after starting it up are you reving it? during startup the engine runs extra rich. reving soon after startup is liable to cause some backfiring as there is excess fuel not being burnt.

not to mention, reving it too soon after engine start is not a good idea to begin with as you are putting excess strain on the motor before the oil gets a chance to circulate thruout.

I first noticed the "backfire" using the remote start so I tried a normal key start followed by a little throttle. Same effect but it is inconsistent. I cannot hear the sound after warm-up but honestly I'm not 100% certain on that.


2. what gear are you in when you are cruising at 1500rpm? try down shifting a gear. then again, you are in the auto.... and when you are cruising, it most likely is switching to 4 cyl mode.

Its the auto tranny. I haven't even tried the tap shifters yet. If it is AFM then fine but the vibration I feel seems unnatural. A tap on the accelerator and it goes away. No hint of a stall.

3. let her break in some more.

you can wait on the A-pillar. its cosmetic.

That would be easier for me if I could wait to get the A pillar fixed at the same time. I expect the dealer to call me back tomorrow and I'll suggest that.

All-in-all I have no complaints. I love my Camaro. Heck, EVERYONE loves my Camaro

Thanks!!

Paul

[CamaroSpike23]

Originally Posted by paulv7260

Its the auto tranny. I haven't even tried the tap shifters yet. If it is AFM then fine but the vibration I feel seems unnatural. A tap on the accelerator and it goes away. No hint of a stall.


Paul

a lot of cars tend to "bog down" at lower rpms. mainly cus you arent spinning the motor much above idle and you arent making much power. add into that that the l99 switches to 4cyl mode when cruising and the slight bog down/vibration is just that of the 4cyl motor pushing a 4000lb car.

[paulv7260]

Originally Posted by paulv7260

A couple of issues:

1. When I start er up and rev there is a mild backfire, not loud but more distinct than a cough.

2. Decelerating then cruising at 1500 RPMS there seems to be a lot of lag and what I think are vibrations coming from the chassis.

3. Car runs smoothly but at idle the lope is noticeable especially under my seat. To be expected with the L99?

860 miles on her. Thoughts from the experts before I take her in? I'm also waiting for the clip to fix the A pillar pop-out problem (its on backorder). Think I can wait until then?

Thanks

Paul

I promised an update when I had this stuff looked at so here it is:

OK, waited for break-in to go to the dealer. Did that yesterday with 2300 miles on her. I was really lucky because the mechanic that looked at my car also owns a 2010 L99 SS AND he is a tranny specialist.

On item 1 he says it is normal as the start-up mixture tends to be rich and leans out as the engine warms. Unless GM does a new program that's the way it is.

On item 2 he says it too is normal and his car does it too. He chalks it up to the program trying to conserve as much fuel as possible.

Item 3 is normal and I figured that out long ago so I didn't ask the mechanic.

The A-pillar fix was done weeks ago.


Paul