I just got back from doing 3 back to back pulls in the evo on a nice long flat road

1. unfortunately when I push in the clutch at 7500 rpms they drop until they hit 4000... then they stay there... so I braked a little bit and put the car into 5th and finally the rpms went down. This happened each time I did a pull... is my clutch starting to slip?

2. On the third and last 3rd gear pull right when the car hit 7500 rpm there was this somewhat loud POP/crunch noise from the passengers side engine bay... the car ran fine all the way home... popped the hood and everything seemed normal; all the vacuum lines and pipes were still where they were supposed to be... any ideas what that could have been? Maybe knock?

Uploading my logs/VD screenshots in the next post too if anyone wants to look


2005 EVO VIII MR MODS:
CATLESS TBE
MUSE LOWER INTERCOOLER PIPE
PERRIN DROP IN FILTER
WALBRO FUEL PUMP
BUSCHUR INLINE MBC SET TO 21 PSI

 

Just noticed my A/F wasn't being logged in evoscan for some reason... it was checked but it showed 0 the whole time.

On previous logs it was 10 at WOT

not sure why it didn't log this time... I guess I'll have to double check next time

Car is untuned

Why are the 3 logs so different? Looks like 1 stands out more than the other 2 so I'm guessing the other 2 are more accurate... I believe the one with 297 hp is the 1st log...

The 1st log had pretty much no knock... besides the 1-2 counts around 3000 rpm.
The 2nd log had about 6-7 counts from 7-7300 rpm
The 3rd log had 1-2 counts from 3500-4500 rpm. 2-3 counts from 6900-7500 rpm then 10-14 counts from 7593 - 7468 RPM then 4 counts at 7437 RPM

I'm guessing the 10-14 counts was the LOUD POP that I heard... was that really bad knock? Or was it something else that acted like knock...


Smoothing was on 3 for the first jpeg, the other screenshots have smoothing set to 5; the green was still pretty curvy for some reason.

 

could just be a back fire. i have seen many evo dsm do this at the track.

 

I'm no clutch expert and I don't know what clutch you have but I've read that some clutches are made to apply more pressure plate pressure with rpm. I'd suggest your clutch was not disengaging until the rpm was reduced.

 

Its the stock clutch... I've done pulls before I've just never seen that happen... and wouldn't backfire be through the exhaust? Do you hear it through the engine? When I think about it, it did sound like backfire

 

If your clutch is slipping your rpms will climb but your accel (speed ) will be slow or remain the same. Its an eary feeling and it's usually associated with a disc burning smell.

 

Did your clutch DISengage properly when you depressed the pedal?

Sound is a funny thing as well... the exhaust is on the right side, so perhaps if it backfired it may have sounded like the noise came from the engine bay.

I'm no expert on those graphs... so take that into consideration... but a loud pop in these cars is typically a hose popping off, or an exhaust backfire.

What mods do you have done? Are you running catless?

 

When I depressed the pedal the rpms went down to 4000 so I put the car in 5th and let out the clutch, then it disengaged properly. Its only happened on high rpm pulls so I'm not sure what the problem could be... also yes I'm running catless it may have been backfire as I checked the bay and no hoses popped off

 

how are your plugs? i know when my plugs are going when i get on it theyll say **** you and misfire lol also id check your throttle position sensor. my mustang would do the same thing and hold the rpms when i shifted untill i put it back in gear, and it was a bad tps

 

I had this problem with my stock clutch. It is slipping. When I'm on the highway and punched it on 3rd gear, I heard a loud pop. After that, my rpm is climbing high and i'm barely moving. I replaced the clutch and that problem went away.