97 gtp misfire/shift issue

[Wilong]

Not sure if this is in the right section but here it goes, I have a 97 gtp with 170k,(91 k motor) plugs have about 3k on them, msd coils and wires, cat delete, cold air intake, new intake manifold gaskets, new fuel pump, new motor mounts. Under hard acceleration the rpm keeps rising and over 3k rpms the car feels like it is misfiring or running against the rev limiter if I let off the gas and hit it again it shifts into the next gear.... Please help!!

[Bluemagic]

Any service lights?
Recent maintenance?

[Rico]

Just started doing this or after coil install?
I know people have had trouble with the MSD stuff.

[Bluemagic]

I think you just found your problem.
MSD coils are notorious for causing issues like misfires and other strange things. You have a set of stock coils to see if it's the coils? Why'd you change the coils?

[Wilong]

I had a oil change about a month ago, mobil 1.. I really don't drive the car much just about 50 miles a week. I changed the coils because I had a bad one and I had a gift card to jegs and figured what the hell I'll give them a shot. The coils have about 500 miles tops on them. No cel lights or anything, this problem just started a few days ago. I love the car but damn every month its always something!!

[Rico]

I can't believe there is not a P030X DTC. So you actually scanned for codes?

[Wilong]

The car will actually run right to red line under hard acceleration before it shifts but over 3k just starts running like I dropped it in neutral or something, but if I'm driving like a normal person, which I never do it runs fine...

[Wilong]

Yea I scanned it the while I drove around and no codes, even the typical cat code didn't come on!

[Rico]

Under hard acceleration the rpm keeps rising and over 3k rpms the car feels like it is misfiring or running against the rev limiter if I let off the gas and hit it again it shifts into the next gear.... Please help!!

????

[Fivefingerdeathpunch]

Switch back to stock coils.

What plugs are you running, what gaps?

I hope you are running atleast 91+ octane fuel.

[Bluemagic]

Stock coils are the best replacement.

[Wilong]

Always use 91+ ngk plugs but I don't remember the gap, I put them in about a year ago when I dropped the new/used motor in

[BillBoost37]

I'll add in my condeming of the coils as well. Swap them, let us know. I'd say 85% that they are the issue.

They are pretty and red, so they match the color on your face when you are pissed about the misfiring.

[Wilong]

I'm going to swap them out today, thanks for the suggestions!

[Rico]

Don't rule out the MSD wires either. Put some AC Delco's or Autolites's on it.