S5 NA Power loss problem (searched)
 

as much as I hate to open a new thread, this problem is really pissing me off.

I'm losing power at what seems to the RPM where the VDI kicks in. ~5500 rpms

it might be losing power as early as ~3800 when the 6PI starts.

The engine still revs up and will make it to redline but very slowly. It doesn't hesitate at all. it makes a clunky sound when I rev it up to higher rpms (regardless of under load or not)

originally i thought i blew an exhaust manifold gasket. i revved it up and it made a loud POP and then it got louder and i had (still have) some vibration in my pedals. I tore it down and replaced all the vaccuum and fuel lines, intake gaskets, and exhaust manifold gaskets. (fixed my very rough idle though)

I also broke the VDI solenoid which i replaced it with a blue solenoid (S4), yellow solenoid (S4), and superglued normai VDI solenoid, none of which worked.

It had the same power problem so i tore it down AGAIN and cleaned out the 5th and 6th port sleeves and actuators and put it back together. still having issues.

It sounds like i have a leaky intake gasket again and i think one of my exhaust gaskets sounds like it is leaking too.

I think that my secondary injectors are not firing (maybe just one of them). I unplugged the injectors and ran the car and if ran about the same. It cut out a little in the every high rpm range but revved up about the same.

bump

and also i'm a bit confused on the direction of the actuating rods. do they push out (short to tall) or do they pull in (tall to short)?

You can try bypassing the solenoids and hook the vacuum lines right up to the actuators. They will open early but atleast you can see if you have power up top when they are open.

Not all the solenoids open the same. Some are Normally open and some are normall closed (valving wise) with no power going to them. I forget which colors are which but you need to make sure that when power is applied to the solenoid at you get air pressure flowing through to the VDI or AUX. you can hook the solenoids directly up to the battery to test this.

Series 5 they push out while S4 they pull in.

does anyone else have any suggestions?

You could hook up some LEDs to the solenoids and run them inside the car to see if the solenoids are working.

ECU have any error codes? Never owned a S5 but I think there is a CEL? Im sure you would have told us if that was on...

no CEL.

latest installment of my headaches

https://www.rx7club.com/2nd-generation-specific-1986-1992-17/no-good-metal-flakes-743037/