HELP! Installed ported exhaust mani and now issues...

Another GP buddy of mine gave me his ZZP plog (he got headers) and when installed it the other day. For the most part everything went smoothly (we had to install it three times cause it was leaking at the crossover the first two times). The third time we got it and I drove the car home and everything seemed normal. It idles just fine and when you drive conservatively, you would never know there was something wrong. But when you pin it it does this sputtering hiccup type thing. Whether it's off the line or if I'm cruising on the freeway at 2 RPMs and then punch it, it sputters and seems to choke a little and then takes off just fine. This for SURE did not exist before I put on the plog.
I've suspected for some time that my cat was clogged so before worrying about it too much I had my ZZP 3" catted DP installed to see if the cat was the problem. After the install there was no change to this issue. A different friend told me he suspects the coils might be the cause because he said he had something similar going on. That just doesn't make sense how a plog could blow coils! :eek7:

Here's a vid of kind what happens. I'm pretty sure this is just me showing how my rev limiter works :cwm27: but it's the same sputtering choking sound that I'm hearing when I pin it while driving, only it only does it for a second.

Make sure your computer speakers are turned up and if you have good bass range you'll hear it better.

Any ideas at all!? :runaround:

http://i286.photobucket.com/albums/ll90/Mattman_2000/Car%20Pics/th_SputteringCar.jpg (http://s286.photobucket.com/albums/ll90/Mattman_2000/Car%20Pics/?action=view&current=SputteringCar.flv)

Hey matt!

This is just a front plog, not the back, right?

Does it feel like a single missfire?

Did you remove the front spark plug wires at all? Check to make sure all boots are securly snapped onto the plugs, and if they are, check to see if any boots may have been torn or punctured. Even the slightest little hole in a boot could cause the spark to arch out to the exhaust manifold or to those little heat shields.

The G/f's 3100 had a miss under load just like yours did. It started happeneing right after I put LIM gaskets in it. I couldn't figure it out, untill one day, idling in the driveway with the hood open scratching my head it misses and I hear a SNAP. Like a electrical spark. Then it was fin and wouldn't do it again. I ran inside, grabbed a spray bottle, filled it with water and some table salt and started to spray the ignition wires. Since the salt water conducts electricity, it mad the car missfire, and I was able to pinpoint the bad boot on the plug wire.

If you are feeling up to it, you could remove those metal sheilds and try the salt water spray bottle method. Just make sure to give your under hood a good bath when you are done.

Hey matt!

This is just a front plog, not the back, right?

Does it feel like a single missfire?

Did you remove the front spark plug wires at all? Check to make sure all boots are securly snapped onto the plugs, and if they are, check to see if any boots may have been torn or punctured. Even the slightest little hole in a boot could cause the spark to arch out to the exhaust manifold or to those little heat shields.

The G/f's 3100 had a miss under load just like yours did. It started happeneing right after I put LIM gaskets in it. I couldn't figure it out, untill one day, idling in the driveway with the hood open scratching my head it misses and I hear a SNAP. Like a electrical spark. Then it was fin and wouldn't do it again. I ran inside, grabbed a spray bottle, filled it with water and some table salt and started to spray the ignition wires. Since the salt water conducts electricity, it mad the car missfire, and I was able to pinpoint the bad boot on the plug wire.

If you are feeling up to it, you could remove those metal sheilds and try the salt water spray bottle method. Just make sure to give your under hood a good bath when you are done.

Thanks for the thorough response Tim!

Yes, it was just the front one.

You know, I know what a misfire is, but I have no clue how to identify what it actually is in real-life? What does a misfire look/sound/taste/feel/smell like? :tongue:

You know we did remove the spark plug wires and that is a fantastic suggestion. I will definitely poke around with those and see if that yields anything. Any other ideas?

Any other ideas?

Nope, thats about all I can think of. You didn't take anything else off, did you?

are your dog bone motor mounts tight?

No and yes.