Rough Idle on Start Up

[SLP LS1]

Cars been sitting for a year, but the last few months the car has been starting up with a rough idle and sometimes it wont start. After I let it run, everything seems fine. But then I let it sit a hour, try starting it up again same thing.

Maybe an 02 sensor?

All I have done to the car is a lid, MTI throttle body, SLP smooth bellows, dual exhaust without cats and Kooks headers.

I did just replace an 02 sensor like 1 1/2 years ago. Why do sensors go bad? LS1 engine may be running rich right?

So where's everyone taking there fbodies to get fixed nowadays?

[OIF1VET]

Check your plugs.. Mine got fouled out at the paint shop, to the point the car wouldn't even start.. Swapped plugs and all was well again..

[Lucky SOB]

Bad gas?

[SLP LS1]

Bad gas?

Possibly, been sitting in there since winter.

[SLP LS1]

Check your plugs.. Mine got fouled out at the paint shop, to the point the car wouldn't even start.. Swapped plugs and all was well again..

I might do that.

I had this happen before like 3 years ago, ended up being the throttle body sensor. I'll just have to take it into a shop that has diagnostics. Hate to take it to the dealer, any places you guys recommend. Vector? C.A.R.S.? Hate to take it out Collins Automotive, too far of a drive for me. I'm off 8 mile and harper.

[OIF1VET]

I might do that.

I had this happen before like 3 years ago, ended up being the throttle body sensor. I'll just have to take it into a shop that has diagnostics. Hate to take it to the dealer, any places you guys recommend. Vector? C.A.R.S.? Hate to take it out Collins Automotive, too far of a drive for me. I'm off 8 mile and harper.

You can pull a couple plugs on the drivers side very easy to see what they look like. If they look bad, I'd try swapping them first before taking it to a shop...

[DETROITMUSCLE]

Try all you can on your own first as Larry mentioned. I believe you can reset the tps by un plugging it for a minute or two and then reconnecting it. Is there an ses light?

[SLP LS1]

Try all you can on your own first as Larry mentioned. I believe you can reset the tps by un plugging it for a minute or two and then reconnecting it. Is there an ses light?

Well I could go through some cash that way, I need to pinpoint the problem. 02 Sensors and spark plugs aren't cheap. I could replace them and still have a problem. Like I said before, it was the throttle body sensor. I'll have to stop by a shop with diagnostics.

SES light isn't on. But since I don't keep the battery hooked up to my car since it's still instorage(sitting in my garage), the engine might take some time to turn on if I have a problem.

From what I remember, it's been a long time since I worked on the car, one of the shops turned off the back 02 sensors because I have the cats off. So the engine light still should come on.

Thanks for your help though guys, I'll probably give a shop a call when I get around to it.

[1BADAIR]

could be many things. after having the batt unhooked the car will have to relearn. how long does it take to smooth out? takes a few to start running on 02's startup doesnt use them.
relearn will take a few drive cycles. then see how it acts

[SLP LS1]

could be many things. after having the batt unhooked the car will have to relearn. how long does it take to smooth out? takes a few to start running on 02's startup doesnt use them.
relearn will take a few drive cycles. then see how it acts

I've thought of that, but I thought the computer stays the same even if you unplug it.

But I think that may be it right there. I haven't had a chance to put the car insurance back on to drive it. This is the longest I ever had it in storage. Before I never pulled the wires off the battery, now that the car sits I don't want to drain the battery.

After the first startup its rough, second it gets better, third its fine. Took it for a drive and it seems to run right.

[OIF1VET]

Didn't think of that.. Larry is right, computer has to relearn idle and such when it has had no power for awhile.. Also, you don't need those 60 dollar iridium plugs, I run NGK BR6EFs(they are for spray), but I haven't sprayed in well over a year and these plugs work great, cost 2 bucks each..Glad to hear that it is running and seems fine now..

[1BADAIR]

the set parameters dont change. The learned stuff gets reset.