whats wrong! wierd shuttering after 4k

[Jory]

I just bought a 04 gtp comp g. after 4k rpm the car seems to be hesitating really bad. im going to try to upload a video to help you guys out

[Scottydoggs]

tune up time? how many miles does it have?

[Neil98gt]

smell like rotten eggs? clogged cat?

[Jory]

I just bought a 04 gtp comp g. after 4k rpm the car seems to be hesitating really bad. im going to try to upload a video to help you guys out

[Bio248]

merged your threads.

you only need one.

[Slick2500]

Looks like it needs a tuneup to me.

[blueguy]

Car sounds modded.

[Jory]

It's bone stock other than a could air filter. And no rotting egg smell or anything like that.

[BillBoost37]

I'd start with plugs and wires.

[crysalis]

Mine did this too. Swapped plugs and found a vacuum leak. Do a tuneup and if not, smoke test!

Here was my video.

https://www.youtube.com/watch?v=y11z3Uj9O5c

[Jory]

Crysalis... That's exactly what mine is doing. I just picked up some auto lite 605s along with new wires going to install them as soon as my car cools off... I will be on the look out for a vacuum leak. What is a smoke test?

[Scottydoggs]

smoke test is when they pump smoke in the vac lines, then watch for the leak via smoke leaking out.

you can also let the car idle, then spray carb cleaner at the vac lines, if the idle jumps up you found a leak. move the lines a bit when spraying them, this helps find cracks that dont leak much due to the weight on them holding them tight.

if the vac leak is large enough the idle will be jumping up and down, hunting if you will, and sound like you just installed a nice loopy cam lol

so if your idle is nice and smooth chances are the vac lines are ok. most of the time.

i do think you'll be right as rain after the plug change tho.

[Jory]

i just pulled out the front side plugs and found them to be acdelco 41-101 they look to be a platinum... let me know for sure...but there brand new

[Scottydoggs]

a cracked plug will also make the car misfire like that, the rear # 6 and #4 plugs (the rear middle and right plugs) are famous for breaking during the install. i use a plug socket, its got a foam insert inside the socket to protect the plug from cracking.

so check for cracks in the porcelain part of the plugs.

[Timing]

those are iridiums

[Jory]

ok after a little googleing i found that its not a platinum and its the ac delco stock brand...so my next question is.. whats better for my car the acdelco or the al 605s car is pretty much stock other than a 180t stat witch im putting in now, resonator delete (old one rusted out) and the cold air.

[Scottydoggs]

ACDelco 41-101 Professional Iridium Spark Plug, Pack of 1 : Amazon.com : Automotive that comes back to iridium plugs.

you may have a bad icm if they are all iridium plugs int he engine, pull the rest, check them out for damage and that part #, if they areall good put them back in.

did you gap the new plugs when you put them in? or just went with what they are from the box?

[Jory]

yeah im using a plug socket. and what do you recommend the gap to be? i havnt put any plugs back in yet cuz i wanted to find out what ones to use first.

[Timing]

just use al 606 or 605 and change them every 10k miles

gap at .055

[Scottydoggs]

stock is .60 but .58 its ok, its where i am. some go smaller but your all stock so keep it close to .60