Miss and popping

**Jivepepper** · 06-29-2008, 11:46 PM

I'm getting a miss and a popping sound from the exhaust between 2-3k at cruise and partial throttle. As soon as I start opening it up and over 3k it feels great.

I've recently installed new Patriot heads and haven't been tuned yet. Plus I had a 3" dumped exhaust made using Mac Lt's. custom X-pipe and dynamax bullets.

I'm scheduled Tuesday for a tune and was hopping to figure out whats causing it.

How bad would it be if one of the cams where off one tooth? Which I doubt but just wanted to ask. Plus I was wondering about an exhaust leak before the front o2's, but I really don't hear one.

Could it just be a tuning issue? But I couldn't image a tunning issue that would cause this?

**wick** · 06-29-2008, 11:56 PM

Its lean and needs tuned.

**Jivepepper** · 06-29-2008, 11:59 PM

Originally Posted by wick

Its lean and needs tuned.

Even at that lower rpm and part throttle?

**wick** · 06-30-2008, 12:00 AM

Yep. You just increased air flow considerably. Fuel needs to catch up. That usually takes place with a tune.

**Jivepepper** · 06-30-2008, 12:03 AM

Originally Posted by wick

Yep. You just increased air flow considerably. Fuel needs to catch up. That usually takes place with a tune.

But you think the MAF sensor would be able to sense that and calibrate for it since it's not WOT and higher rpm or out of it's usable range? Maybe I don't totaly understand it.

**wick** · 06-30-2008, 12:05 AM

Tell ya what. Mine did a similar thing with the popping until I ran it wide open. I got my tune at SGS and it all went away. I know its different cars but thats probably what it is.

**Jivepepper** · 06-30-2008, 12:26 AM

Originally Posted by wick

Tell ya what. Mine did a similar thing with the popping until I ran it wide open. I got my tune at SGS and it all went away. I know its different cars but thats probably what it is.

Well I'm going to SGS. Does you car use a mass air?

**Wolfpack Speed** · 06-30-2008, 08:44 AM

Assuming your car is mechanically sound, you need to get her tuned before anything else. Some have good luck with Patriot heads, some don't. Either way, after an upgrade such as heads a tune is mandatory. Is your car NA???

**SonofaBish** · 06-30-2008, 08:54 AM

Originally Posted by Wolfpack Speed

Assuming your car is mechanically sound, you need to get her tuned before anything else. Some have good luck with Patriot heads, some don't. Either way, after an upgrade such as heads a tune is mandatory. Is your car NA???

If i remember correctly, its supercharged, which makes the tune all that much more important....

Get a tune and then look for reasons if it still exists....! good luck!

**Jivepepper** · 06-30-2008, 09:37 AM

Originally Posted by Wolfpack Speed

Assuming your car is mechanically sound, you need to get her tuned before anything else. Some have good luck with Patriot heads, some don't. Either way, after an upgrade such as heads a tune is mandatory. Is your car NA???

It's supercharged. I'm just trying to make sure I not going down there and Dave not be able to tune it. It's 200 miles away and very expensive. Besides it hunting when coming to stops once in a while and the slight miss it seems to be fine.

Originally Posted by SonofaBish

If i remember correctly, its supercharged, which makes the tune all that much more important....

Get a tune and then look for reasons if it still exists....! good luck!

Thanks. You are right it's supercharged.

It would be terrible to have to fork out 400 dollars for nothing.

**SonofaBish** · 06-30-2008, 11:20 AM

Originally Posted by Jivepepper

It would be terrible to have to fork out 400 dollars for nothing.

Definitely...

I know my car is a GM, but when it was N/A and I had the cam put in my car, it wouldnt even run until i got a mail-order tune put on the computer. The thing would fire up and only run for a couple seconds...

Especially since your car is blown, the tune makes all the differnce in the world. I am tuned very conservative on purpose, but when we were messing around on the dyno, there was 100rwhp left to be had at the same boost level (messing with fuel and timing only), so that shows just how much of a factor your tune can be. We backed it off though, since I wanted the car to run "conservative"

**Jivepepper** · 07-04-2008, 11:39 AM

It's still doing just not as bad, He said it was rich. But whatever he did it was not enugh, Man I wish there was some place local who could work on it, SGS is so far away.