Lost on what to look at now. 3.4l firebird

[94punisher]

So before the meet and greet the engine was rebuilt and had no issues until last weekend. I took out the A/C system out and put a delete in, new alternator and a new cold air intake. Drove the car around 200 miles and was having a issue at 55+ MPH. The car would shake and it seemed to bog out but could still accelerate some but the shaking was violent so pulled over and shut it off re-started and all was good until above 55+MPH again. Limped it home that way sporadically having to pull over and re-start it. Later found a broken trans mount and fixed the mount. I'm still having the issue of where it wants to shake and bog out at higher speeds then 55 but the shaking is a lot less. Not sure if it's a transmission issue or what. All fluids are good. Not sure how many miles on the trans or if it ever had work cause there is almost 200k on the car. I'm leaning towards something being up with the transmission but wanted to throw this up to see if someone else has experienced this cause I looked at past posts and some came close but I already checked besides ripping apart the transmission or rear end.

[1BADAIR]

misfire

[Fbomb]

Judge are you in GR now or Lapeer? I've got HPTuners on me and we could scan it.

[94punisher]

I'm in GR. Live in Walker. I tried to drive it again tonight and it was worse. Was bucking and was getting spikes/drops in RPM's. Had a back fire too.

[NullHead]

Plug wires went bad maybe. Im guessing missfire

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[98blackbeauty]

My guess would be you got plug wires burnt on exhaust manifold when doing to the delete.

[94punisher]

Could be a posibility with the plug wires, didn't notice anything that appeared out of place. Haven't had too much explore time other then making sure I have everything plugged back in and the fluids levels. I'll have time in the morning again and they will be first on the list to check. Trying everything I can before taking it in somewhere cause from running good to this within 200 miles of doing some work on it, hard to believe that the trans went to hell with no prior signs.

[94punisher]

All the plug wires are good and seated.

[98blackbeauty]

This does have the symtoms of the Opti devil getting you. When you did the AC delete did you disconnect any of the radiator hoses? There is also a plug to the opti that comes in passenger side from the top. Next guess would be grd connection, which could affect PCM and cause trans shift to be off. Or Vacuumn hose disconnected or cracked.

[NullHead]

Is the check engine light on? If so, scan it first. Then with the engine running get some soapy water, or windex, and spray your plug wires and look/listen for sparks. Sounds like a missfire but doesn't have to be. Gotta start somewhere to eliminate things that it could be. Really, you pretty much need to have it scanned in order to know for sure where to start.

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[hoogiesngrinderz]

This does have the symtoms of the Opti devil getting you. When you did the AC delete did you disconnect any of the radiator hoses? There is also a plug to the opti that comes in passenger side from the top. Next guess would be grd connection, which could affect PCM and cause trans shift to be off. Or Vacuumn hose disconnected or cracked.

No Opti on the 3.4

Hard to say. Could be anything from a bad wire/cracked porcelain on a plug to a leaking intake or plenum gasket.

[94punisher]

No check engine light on. Checked the wires again with the soap and water didn't see anything from them. Took it for a test drive and its gotten worse but like everyone's saying it seems like its misfiring. New wires and plugs less then 2k miles ago.

[zeeman]

check fuel pressure. I would throw a filter on it for s&g.

[Fbomb]

Well I don't have to work Weds-Fri so hit me up. I'll PM you my number.

[94punisher]

Sounds good Vinnie. I have Friday/Saturday off so I'll give you a call later this week. It'll help to have another view on it.Fuel Filter is new along with the pump.