Hello Everyone, please forgive me if this is not the proper heading to post this under. This is my first post here so I am still finding my way around.

Is anyone reflashing the ECU after mods? I dyno'd (sp?) my 2003 Touring at stock and it put down 238whp. Then I added the UR Underdrive Pulley Set and Nismo CAI. I reran it on the same dyno in similiar weather conditions (may have been off by a few degrees, nothing significant) and my best run has dropped to 230whp.

Now I certainly don't expect to jump to 400 horsepower, but to lose from my stock pull was a little (understating) disappointing.

I have done some reading and the only thing I can find is some statements about the ECU going into a limp mode/safe mode from the added air flow, causing a loss of power. Supposedly this is a common thing with intake and exhaust, but I dont really see anyone talking about ECU changes on the forums.

Any ideas? Any help? Thanks in advance for any replies, love the site!! This has me confused enough to come out of lurking mode and actually post!!

Craig

 

Sometimes you will lose when you put on a CAI.
I had a baseline of 229 and put on a UD pulley, high flow cats and a Y pipe and only gained 10 hp.
I have not tried it without the CAI i had on it but, i have taken it off and the vehicle feels better without it.
Alot of people claim you lose some with the CAI though.
Plus, it may have been hotter or more humid which will play with the numbers also.

 

Thanks for the reply DayBlueZ! Have you done anything with your ECU yet?

Can anyone recommend a tuning shop that handles the Z in Florida? (Preferably Central Florida)

Craig

 

Nope, nothing to it yet. I'm saving up for the Emanage Ultimate.

 

You probably should let the Z have a cool off perod for dyno runs, you can vary up to 15 WHP gains. Getting off the freeway and having a dyno run doesn't work too well (I did that a few times).

 

NA tuyning for the Z is non-existant correct?

 

Shooting for 400hp? Save your money and get a supercharger or turbo. No you don't reflash ECU everytime you get a bolt on.

 

Thanks for the comments everyone. I am still in a learning stage here, so I appreciate al the info I can get!

It sounds like I will just continue on my six month plan of adding headers/exhaust and then the Vortech S/C. I will worry about the ECU when I get to the S/C part and will probably end up with the AEM EMS..we'll see!

Thanks again to all, great (and very helpful) site!

Craig

 

Ok, just a guess here : What type of gaz (octane) did you use on the second time?

 

I actually used the same 93 octane from the same Gas Station...Sort of a creature of habit.

But that's something I didn't even think of, thanks for the guess.

Craig

 

I think you could probably give it some time for the ecu to adjust to your mods, how much time did you wait to dyno your car since the mods?

Also I dont know if it might help or not, but probably reseting your ecu could help, allthough I recomend waing first to see if after some tim ethe ecu adjustes, if it does not, then try resetting it and wait some more time...

 

I installed the parts on a Saturday and ran the dyno on the following Friday, so almost a week. How long does it usually take for an ECU to readjust?

Craig

 

That should be enough time...

 

you failed to mention your a/f changes. there's rich, then money, then lean. if you got lean with your mods, a reflash to put you in the money zone will add hp. if there were no a/f changes, well, at least it looks nice.

 

Haha thanks Z BOY, unfortunately I did not get a run with the A/F (I know I know ), so I don't know where this is at right now. I am sure it is the majority of the problem.

I am not going to worry about it anymore, like you said - it looks nice. I am going to stop all mods and wait for the 06's to come out. If nothing huge changes and I just like the little differences they make I will just trade up to that.

Thanks again for all responses!!

Craig

 

maybe you can call them and pay extra for them to email you the dyno file with the a/f, or did they not hook up the a/f sensor at all?

 

No, its my fault completely, I told him not to even worry about the A/F, just give me an HP run. I just wanted a quickie check since I caught him on my way home from work and we both wanted to get going. Maybe I will take a ride up this weekend and get a full run, curiosity kind of has the best of me now. I will post again early next week with results.