Hard ticking noise in 2500-3500 RPM
 

hello everyone,

I have a really frustrating problem, trying to find it over 2 months!
I have like a knocking noise, sound like metal ticking, only under load (so I can't check it on stands) only from 2500-3500 rpm from the front of the car
sound like it getting worse with time, now even can be heard from 1500 rpm
https://youtu.be/5B148c_Qv9E
the noise started after I fuel in a different gas station then usual
(I refueled 4 times at my regular gas station from then, and even add 15 liters of Toluene)
2 weeks before that I changed my clutch (to OEM one) and changed the final drive on the differential (from 4.1 oem to 4.556)
things I done already to trying to find the noise:
change the shocks+hats, the 2 front hubs, steering ball joints, disassemble the sway bar and the undercar shield.
engine mount, bushings, the two hydraulic timing tensioner, change the clutch again, swap my gear.
i don't have any error code, (my car have ECUTEK+UEL)
check on my live parameters with the ECUTEK scenes like everything is fine, EGT, fuel pressure, knocking etc.
(the car is also feels find, no power loss or something)

I'm so frustrated, tried all kind of good mechanics, I have no Idea what to do next, I will be glad to hear maybe you guys have and Idea:cry:

Thanks!

[ame]https://www.youtube.com/watch?v=WAdC7B7xYEU[/ame]



fix: https://www.ft86club.com/forums/showthread.php?t=133606

I can almost guarantee you that it's this.

Sure does sound like it.

What did you do to fix it?


humfrz

Sure sounds like @ermax solved this. What causes it to break?

unfortunately it's isn't it, I checked it :(
and the noise don't happen after 3500 RPM no matter what, I can track the car and nothing, but on the way home on normal driving it's all the time

Exhaust header bolt is loose or there's a pinhole leak there. At high rpm you're building up more pressure and it's sort of sealing itself but then opens up and you can hear it down lower. I have something like this happening on my beater suv.

already checked it, it wasn't it

I found the problem, it was one of the direct injectors,
why? don't know yet, maybe the fuel? maybe detonation?
changed one and the knocking vanished.
why we didn't see any fault on the ecu? even when doing live logs on every parameter :iono::iono::iono::iono::iono::iono::iono:
hope my tuner have an answer for that.
interesting if on the stock map it was giving an error :mad0259: