I hope this is the right place to post this, I'm in dire need of advice

My car, 2.4l FP red E85 tune recently developed an issue where as soon as it gets to 4k rpm it just stops dead in its tracks essentially, wont pull at all and almost seems to have kind of a quick repeated backfire. Really hard to explain, I could get a video if need be.

I've been advised to first change the plugs and gap them to 20. Its probably been a really long time since they have been changed. If that doesn't work I was told to look at getting the FIC 1100 injectors refreshed or purchase some new ones altogether. They are pretty old as well and did sit for quite a while with e85 in them.

I dont have a lot of time or money to diag the culprit and I'm not a great mechanic either. This is making my hair fall out just wondering what you guys thing the most LIKELY culprit is.

its not the tune as Adam Blevins tried his own different tune and had the same issue. Probably pretty much appeared overnight, was pulling really hard before.

 

First things first do the spark plugs gap them to .20 then do a boost leak test if I had to guess it kind of sounds like a massive boost leak

 

I too would start with plugs. Gapped at 23 if allowed (before blowout)

If its a evo8. Use bpr8es they are about $2.49

 

Check the coil packs?

 

Thanks for the responses guys. I will definitely start with the plugs and hope that clears it up. Its weird how its exactly when the tach hits 4,000. its like the car does NOT want to go past that point. But before 4k it pulls strong/normal.

I'm about to go for a drive. Unfortunately cant get the plugs today but I have them on order to get here monday. Ill report back if I notice any other details but Ill be taking it pretty easy of course.

This is nervewracking/annoying as I just had the engine completely rebuilt just over a month ago. But kind of fun to try and figure out as well haha. Learning a lot about cars with this evo. Always soemthing to fix.

 

what should I be looking for specifically? I'm very new to this. I only know the absolute basics, not much experience working on my own car but this evo is quickly changing that.

 

Sadly my method of checking would be to take one coil out at a time to check if the engine reacts by sputtering or idling different. Not scientific. Check out this video from another Evo owner:

 

I will definitely give that a watch and look into. Really appreciate the responses guys.

 

You're not in valet mode, are you?

 

Ohhhh lol I never thought of that lol been there done that a couple of times in tephra doing a pull onto the freeway lol

 

As per my understanding , when you are getting out of vacuum you have a misfire .

If plugs are changed and issue remains then you need to check your injectors , they are not opening as they should.

 

Does it happen just on boost or does it happen both with/without a load on the motor? I would try to find someone with an oscilloscope and check the waveform of the crank sensor, and cam sensors. As far as the coilpack I'd just check voltage at each coil or check spark at the spark plug to see if its missing. Are you speed density or MAF?

 

Or are you sure your on the e85 maps and not on 91 maps? AKA alt maps

 

+1 for coils packs. I had the same issue and one coil ended up dying completely.