Searched, but I can't find anyone with the same problem.

I just noticed it within the last week or so.

When I'm driving, anytime the engine gets around 2000rpms, it feels like the car loses some power, and then regains it around 2300-2500. This might be referred to as "surging"? Anyone else experience this or have some advice? I spoke with Greg (blasian) and he's experienced something similar, except his car bucks bad at a certain point. My car doesn't do the buck thing, but it's a noticeable loss of power. Feels almost like falling out of boost, then spooling up again.

I already have cleaned my air filter, reset the ECU via battery disconnect, cleaned the MAF. Replaced spark plugs last fall with NGK Iridium, so I'm sure it can't be time to change those. (?)

 

Where did you get gas?

Same thing happened to me. Fuels that contain ethanol can go bad quicker and have a much lower octane.

Get it checked, and if you have any engine management, datalog a run and if she is knocking, drain the fuel and get some better fuel

 

It's normal 91 octane from the local Lucky Seven (local store?). I forget where they get their gas from.

My car is stock ECU-wise. Only have a popcharger and exhaust. I tried putting the stock airbox back on, but the same thing happens.

There is no knocking. There's no SES light, but I'll scan it soon just to check for any pending codes, etc.

 

My car didn't throw any codes either, the ecu and UTEC just started pulling an *** load of timing, causing the car to fall on its face.

 

Just scanned it. No codes.

Any idea what the reason could be?

 

My guess -ECU.

but two things can happen here.
A) take it to a Nissan Dealer here in Duluth/Cities to have it checked out or inquire as to what the issue might be.

B) come to the meet this saturday and see if you can have the guys looks at it Saturday night. Either way, you won't be alone if something does happen.

Hope it works out man. Sorry i couldn't be much help. I've only heard of similar issues on Subie STI's and the old Boxter's through my buddy and his forum a while back.

 

What are your mods? What year and how many miles? Auto or 6 spd.?

 

Mods: JWT Popcharger, Apexi N1 Evo Exhaust.

2003 65555 miles, 6-speed mt.

Don't worry Alex, I'm considering making it down regardless.

 

can you duplicate this anytime? hot and cold?

 

When cold, it really loses power. So yeah, it's a lot worse when cold.

I can duplicate it anytime, yes.

 

my thoughts:

-Bad gas - but being it is easily duplicated doesn't seem to fit

-TPS (throttle position sensor) or throttle body - no SES light doesn't seem to fit

-coil pack - maybe.... but I think you would be throwing a code; probably a misfire code

-You could have a fouled plug regardless of just changing them

-Slight vacuum leak... but your idle might be affected as well if this were the case

-Issue with the MAF?

These are just some thoughts. Thing that is odd is that it doesn't throw a code. If you bring it down, I can have my mechanic take a look if he is around

 

just a shot in the dark
when you changed plugs last fall...could it have been doing this back then but you just noticed it now?

initially thought it was MAF...but you tried cleaning it already. unless the sensor is just messed up

 

^^ I remember the car always having complete smooth acceleration.

I might be coming down this weekend. If you meet up with everyone, maybe we can figure something out.

Would it be worth it to put the old oem spark plugs back in and see if it makes a difference?

 

Hey, I am new to this forum and I just bought my 04 enthusiast mt about 2 months ago. I am noticing this same problem however it is in the upper rpm ranges at medium acceleration. The general "power loss" seems to happen at random and is throughout the entire rpm band, but I notice the "cut out" around 4500 and it will kick back in around 53-5500. Not sure what the problem is and with my crazy work schedule I probably won't be visiting a dealer any time soon. Just thought I would hop on the power loss cutting out slower than normal somethings wrong bandwagon! lol

 

[QUOTE=Silverstone-Z]It's normal 91 octane from the local Lucky Seven (local store?). I forget where they get their gas from. QUOTE]

It could be your gas. Lucky Seven may not be getting the same gas like Chevron, Shell etc..

How long has this problem been going on?