weird power loss, intermittent
 

okay, here is my history! new engine not even 1k! new tranny! new plugs/coils/wire
mazdaspeed CAI/ obx headers/ r1-t exoticspeed 3in cat-back/AP pulleys!

ok here is my problem! its intermittent! on idles = perfect if i push rpm to 9k on neutral everything is fine! now if i push rpm in gears pass 7k it makes a weird noise, like a ratteling coming from the engine( not great at all)+ loss power over 7k through 9k, very bad noise from engine!
runs very good apart that, starts on 1/4 turn even in cold temp! idles great all the time, no grinding noise at all from engine! i checked the headers gasket...

here is my thought! they said at the dealer that my old intake manifold had a problem( clickling noise in the intake) so i went to the scrap ward and got a use intake manifold!
is there possibility that something is obstructing the variable intake system ? cause it sound like when i rev from 7k to 9k something is obstructing somewhere

no cels at all under any conditions
well except for that p0411 cel ( secondary injection pump)

Might want to check the VDI, both the solenoid and the actuator.
Only thing that comes to mind so far.
Did you install the used manifold you got from the scrap yard?

where is this?

The actuator is at the top of the manifold, check it with a vacuum pump and see if it holds vacuum.

The solenoid is almost in front of the oil filter.
When you remove the upper intake manifold you'll see three solenoids stacked on top of each other.
The top is the AIR, the middle is the SSV, and the bottom is the VDI.
Swap the AIR and VDI to see if the sound goes away.

This should help you locate the VDI components:
Attachment 148667

And watch this to see how to test the actuator:
http://www.vimeo.com/5353829

i have to say that my air is no longer in fuctuin as i have obx headers! i left the secondary air pump unplugged! but that is not the problem!
so i do need to remove the manifold to switch these solenoid?

I've heard that some people can do it without removing the UIM, but I couldn't do it.
And don't bother moving the whole solenoids, just swap the vacuum lines and wire harness between the AIR and VDI solenoid.

Also don't rule out the actuator.
If it has a pinhole, it can't maintain vacuum and the valve can't open completely.

Also you didn't answer my question about the manifold... do you currently have the original that the dealer told you had a problem or are you using the one you bought from the scrap yard?

the one from the scrap yard! the original one .. they kept it and they told me they threw it away!!

Right. :icon_bs:

What octane gas are you using...reg or prem? Where do you live?

1. Check all your vac lines are installed right to the intake or capped off.
2. When you installed the AP under drive pulley did you mark the plate thats right behind it? if you intsall the plate wrong=back wards or upside down, your e shafe sencer will throw a cel.
3. Compression test. When I lost my first engine thats what it was doing till I ran it on the freeway and went into limp mode. Could not get past 3k or 4k rpms.
4. Colgged cat?

no cels! pulley was installed by dealer, i use 94 octane from petro-canada! cat is brand new from dealer under 2 k!

i dont know much about this engine! i checked under the hood and all lines seems ok connected :(
fuck i dont know whats wrong! it might be the intake??? but how to trouble shoot it??? i dont know much

Have you checked your MAFS? mass air flow sencer?

even with no cel?

Yeah the wires get all dryed out and when you remove it to install a CAI you can crack them and not even know it. Cracked wire = short. Checkem it!

i read about the VDI and is it right that this valve opens at 7200rpm?
because my loos of power begins exactly at 7200rpm, feels like there is not enough air coming in, the rpm want to go up but it seems hard to! it feels like no sucking enough air.....
is this a commun problem these solenoid to fail? i will check the MAF wires tomorrow, thanks

7250 RPM if you want to get real technical ;)

The solenoids (AIR, SSV, VDI) have been known to fail.
Sometimes its not the actual solenoid, but the wire harness that connects to them get tarnished from weathering/poor seal.
Sometimes just simply cleaning the contacts in the harness and solenoid have corrected the issue.

maybe its good to say that since i have mazdaspeed CAI, i blocked the hole of the vfad( the vaccum line) with a bolt

still no cel! wow it pisses me off!

Is there a reason you didn't just cap the nipple behind the throttle body?
Attachment 148870

Its probably better to do this and if you don't have a vacuum cap, Autozone sells a variety pack for a couple bucks.

ok ill do it! but that is not the cause right? i'm pretty sure no but anyway! thanks. i'm going to the dealer monday

they say they can move actuators with the computer in the garage!

If a vacuum leak was introduced because of your bolt in the vacuum line... possibly a "loss of power" but not a clicking sound...

Yup... their WDS can cycle the valves and will definitely help because they are activating the solenoids and actuators with it.

i have moved freel by hand the actuator of both ssv and vdi! so that should means that they are not defective right? should be the solenoid?
i also read that my obx headers has the sec air hooked up so i reinstalled the connector

okay buddy thanks for all ur help but a miracle just hapened! as i stated up! i reinstalled the air connector, moved both actuators by hand without any resistance, reset the ecu with the ''20 pump brake procedure'' went for a test drive= still the cel but no more power loss :) everything pulls very very hard even past 7250rpm! wow wow wow! i pulled 4-5 run 1-2-3 gears without power loss!
tomorrow i will go erase the cel at my friends place with his scanner!

So you had the air pump's wire harness disconnected and all you did was reconnect it?

yes!

weird hey? i'm confused too!

well the problem was that i killed my brand new cat ! dont know why ..........mmmmm
welll i'm putting in a thm mid-pipe on it and we will see if its fixed now!!!

Any updates on this issue, i may be having the same problem...80mph on highway and rattling noise with power loss. cleaned MAF fixed for a little while comes back intermitently. Have a K&N Typhoon intake installed (only performance part).

Please give us the history on your car. Model and miles etc. The service it's had parts replaced. Type of driving it gets(long commutes, short trip), fuel used(reg or prem), ever flooded. Just any thing that you can add. Done any decarbon cleaning?

new spark plugs and wires, coils checked and in good condition, catalytic converter checked and in good condition (not clogged). I've thought about maybe having a timing belt issue which I have not gotten checked yet. Like the other person in this post, acceleration on neutral is perfect goes all the way to 9k without any rattling noise, only makes the noise accompanied by power loss while on freeway at 75-80mph 4500rpm. Before MAF was cleaned power loss would come at 50mph or so. Something we have noticed is that exhaust fumes are not hot, just barely warm (this was a few months back when it wasn't cold yet). You could put your hand on the end of the pipe, block it and nothing, it was just warm.