A friend of mine had a similar issue. He swapped transmissions and the problem went away. Maybe the vehicle speed sensor?

 

GOt to the track today. Car bogged EVERY gear this time. Opened hood. Finally found hopefully the issue. Cracked cam sensor

what yall think? I just left autozone. Going to swap a good sensor back on and re run and will update

 

Um, yeah. That could definitely cause a problem.

Good luck, dude. I hope that's it.

 

Well. It didn't fix the issue...

I notice when i shift earlier i feel like it wasn't happening as dramatically? Sometimes it bogs/sputters hard for literally a whole second where other times it feels like it hesitates for just a quick little "blip".. idk how to explain it.

My tuner now thinks it could be fuel cut. he said 9 out of 10 times if its fuel cut its due to wiring? like a bad ground or loose connection somewhere is what he is thinking.

i just got home from the track. going to let the car cool down and tonight or tomorrow night go over all the connections for a 10th time.

before leaving i wanted to make 1 more pass with the forge dv. i swapped it out, was tightening up the last hose clamp and sure enough, it fcks me. decides it wants to do the whole "not tighten and just click then get loose again" ordeal. So didn't want to push the car with a halfway tighten bov hose.

 

FWIW, I once had a main ground wire that was corroded just past the terminal. It looked all good until I gave it a nice little tug.

 

Here's another thought i wanted to add... I was launching my car pretty hard. the car has a comp stage 2 clutch which is supposed to rated for 500 ft lbs. (my car makes 475/408 on dynojet). i was having to slip the clutch at the launch to keep as much stress off the tcase / trans.

a random guy at the track was telling me that the clutch may not be able to hold the power and after the hard shift it may seem like its bogging but really its just "blowing out the clutch"...

what exactly would he be meaning by this, and is it a possibility?

 

He's thinking you overheated it and it was slipping. If that were the case, it wouldn't have started grabbing until you let it cool down for a bit.

 

Its not a bad thought but it would just slip for a second it would slip right through especially as boost builds.

 

Okay. Makes sense.

I was asking about my injectors earlier because I got these injectors used and they weren't the cleanest set. They look old and dirty. But I just had them cleaned and flow tested and everything checked out.

Thats is why I was wondering if they could be bad even though the tested okay

 

Here is another thread of a guy having similar issues.
https://www.evolutionm.net/forums/evo-engine-turbo-drivetrain/666947-misfire-after-shift-under-full-boost-2.html

Turned out to be that he needed new valve springs. Which could be a possibility?

i have a completely stock motor minus Kelford 272 cams. Stock valvetrain. (Don't ask why the PO decided to put cams in and not go ahead and do springs/retainers)

What do you guys think?

 

Data logs would help. Otherwise, you could be shooting in the dark for a long time....
😕

 

I'm getting a laptop today and going to order I guess a 2.0 tactrix cable

 

Nice! Two things every Evo owner should have, unless they are baller enough to have a shop do everything. LOL

 

If your clutch was slipping the RPM's would go up. From the video that is not happening. Valve springs are in interesting note. I've never heard of that. If that's legit and you're on the factory springs with those cams then that could be contributing to the problem. I didnt read the thread but Im curious as Im typing this what the logic was behind that.

Im not one to just start replacing parts as that gets expensive fast. But with those cams you should have upgraded springs anyway so replace them!

 

Yeah I definitely don't want to just start throwing money at parts. I just purchased a tactrix cable from their website. Hope it gets here quick!