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View Full Version : Miss and popping



Jivepepper
06-29-2008, 10:46 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, 10:56 PM
Its lean and needs tuned.

Jivepepper
06-29-2008, 10:59 PM
Its lean and needs tuned.

Even at that lower rpm and part throttle?

wick
06-29-2008, 11:00 PM
Yep. You just increased air flow considerably. Fuel needs to catch up. That usually takes place with a tune.

Jivepepper
06-29-2008, 11:03 PM
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
06-29-2008, 11:05 PM
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
06-29-2008, 11:26 PM
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, 07:44 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, 07:54 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???
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, 08:37 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???

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.


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, 10:20 AM
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" :pepper:

Jivepepper
07-04-2008, 10:39 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.

2001GTTT
07-04-2008, 12:00 PM
my car is doing this exact same thing, and all i did was clean the motor! lol. scanner says misfire in cylinder 7. great.

Jivepepper
07-05-2008, 04:11 AM
I hate a miss.