2 days ago i had my Motordyne plenum spacer installed (5/16) with isothermal and copper. i also already have nismo exhaust, labree test pipes, and nismo cold air intake. when we put in the spacer, at first it felt laggy, but i know at first it usually does that until the ecu reads the mods right. well after a day of driving close to 200 miles just to get everything broken in, the next day i went out again and it only seemed a little bit better than the day before. yesterday i realized that we didnt re-set the ecu, so we did by un plugging the negative (-) plug from the battery. the sound seems a little bit better now, but still doesnt feel like i have all the power i had with just my other 3 mods, especially in 1st and 2nd.

i have an auto 04' touring 350 and have the 3 mods listed above.
can anyone tell me some reasons this might feel this way?

could it be because it doesnt run right with cold air intake?

or is it just not something thats not good on auto 350's?

or maybe theres something that we messed up on the install? like tightening the bolts too much or not doing something...?

or do i just need to be patient and keep driving around for another few days until it fully runs right?

ANY HELP WOULD BE APPRECIATED, BECAUSE IVE HEARD GREAT THIS ABOUT HP AND TQ FROM PLENUM'S AND MOTORDYNE. THANKS A LOT.

 

I've heard some people here say that a plenum spacer and CAI don't mix well.

If you had a leak you would either hear it or have a rough idle.

I would leave the battery disconnected over night to resest the ECU. If that doesn't work I'm not sure what else to try.

Maybe someone else here can help you more.

 

do the actual ecu reset procedure, not the battery terminal method.

http://www.technosquareinc.com/350reset.htm

 

Very useful! Thanks!!!

 

the pedal method does **** (compared to pulling the battery for 24hrs).

 

Chebotso has a point. My car feels sluggish with my new exhaust. But when I reset the ecu using the pedal method. It comes to life.

 

if i just disconnect the battery for 12-24 hours and reconnect it, about how long or how many days of driving around should i wait for it to re learn correctly?

 

if you pull the battery for 24hrs and it still is sluggish, then that means there's a leak or something else is wrong. the ecu won't have dummied down the a/f at that point, so there's something else that is wrong.

 

take off the nismo cai and put the stock box back on...throttle responce is quicker without the cai...

 

First, I would ask a mod to merge both of your threads into this one. https://my350z.com/forum/2003-2009-nissan-350z/176814-think-i-might-have-lost-power-with-the-plenum-spacer.html

Then I would check to make sure the rubber oil fill ring is not caught in the edge of the plenum causing a vacuum leak. If that is fine, check for any other leaks using carb cleaner (don't forget the iso thermo gasket could be leaking as well, so check that too). Next properly reset the ECU from the info on the Technosquare site like it says above.

Chris

 

if there was a leak would the car be idiling funny?

 

I have the same vehicle. The ECU sucks. That is your problem. The 04 ECUs are the worst of all of them. It will not let the mods do their job. I put on a Kinetix plenum and pop charger and test pipes and gained 5hp. I ran a 13.39 before these mods and haven't been closer than 13.5 since. I also put on the 3.5 rear. I did go from steady 13.7 to steady 13.5's

The peddle method is crap. It doesn't really do it right. I'm not sure about the battery method but, if you have the factory reset it, that is the way to go.

If there is a leak you will hear a whistle.

I think the stock air box is a better choice than CAI also. I actually lost 8hp and 7tq on a dyno with a CAI

 

Uh, no. I've reset my ecu twice, and both times it was dog slow immediately afterward. It took a good thrashing to get the car anywhere close to where it was before the resets.

 

maybe it depends on the year then? mine has a noticeable difference right off the bat.

 

After seeing several dynos of long tube CAI's, I'm no fan of them.

 

I'm also thinking to go back to the OEM intake. Do you know any one tried this new Nismo drop-in filter? where to purchase it?

 

please tell me how the hi flow filter works for you when you put it in, because from how your explaining how the spacer worked for you and the CAI touching the hood, i can relate to that so let me know how you like it and how you think it is running. thanks.

 

Hack your Nismo into a short ram, buy a Popcharger or put the stock air box back in. 10whp in my car on the same dyno with a Popcharger+plenum(same thing) over the AEM+plenum, no tuning and much better throttle respone. Ive told several people about this and they all were doubtful but after going short ram they believe me. Try it and see for yourself....

 

What is the reason that the cai isn't as good? Is it just the throttle response? Its slower? This car needs more horsepower.