Dave B

A friend of mine has an 01 SE 5MT with a Stillen POP intake. For the past month or two, he's reported that his car has some erratic bogginess which usually occurs after a shift when the motor is cold. He isn't a car guy at all. A CEL light had been on for about a month too. I plugged in my laptop and the code showed a slow response on O2 sensor 1, Bank 1. I cleared the code and logged the sensor. It seemed to be doing fine. I took car for a spin and went full throttle in 1st at about 2000rpms and the second the tach swept to 4500-5000rpms, the motor felt like it hit a wall, almost like a very soft rev limiter. The rpms climbed very slowly. I shifted to second about 5500rpms and when the tach hit upper 4K, I felt the same thing though not as extreme. The first thing I thought was vacuum leak so I popped the hood and inspected the POP intake. It looked okay, but I removed it and reinstalled it just to be certain. I took the car for a spin and it seemed to do a little better, but it still felt weak above 5K. From what I remember of VQ30s, they have a decent pull from 4500-6500rpms. I know my VQ30 in my modded 96 was very strong and his 01 felt nothing like that. Now granted, there were two people on board, full tank of gas, 90+ degree temps, and I'm use to my significantly quicker G35, but there is some seriously wrong with his car. BTW, I did hear the butterfly valves open at about 4900-5100rpms (noticed the induction noise change).
I wanted to put the stock airbox back on, but he tossed it My guess is one of the following culprits:

1) Dirty MAF sensor from the K&N filter which has been on there for 3 years now. He said he cleaned the filter about two weeks ago and driveability didn't improve or get worse. I'm a bit worried about his skills when it comes to reoiling a K&N filter.

2) Slight vacuum leak somewhere between the MAF and TB. I'll probably hook up a vacuum gauge to see what the vacuum is at idle and at various no load rpm ranges.


I plan on cleaning the MAF and inspecting the intake tract. Does anyone else have any ideas?

Also, what in the world is that vacuum accuated plunnger device mounted on the TB that appears to be associated with the throttle accuator arm?

Dan5.5

i am not sure, i dont have a 2001, but i've read alot about the vias on those cars going bad, and it kicks in at the described rpm. I am sure someone more experianced can help you... but to me it sounds like the vias.

good luck

NmexMAX

iTrader: (22)

A soft limiter wouldn't feel like a faulty VIAS. It's not that bad/noticeable. I'd say rotten MAF &/or coils.

mad2kmax

iTrader: (4)

I would say that sounds like either a faulty MAF or a dirty one. I had the same problem for a couple of months and I just recently went to the store and picked up CRC's MAF cleaner and went to town with it. Problem solved. The cleaner cost me $6, which is a hell of a lot better than the $110+ I would have payed for a new MAF. Give it a try.

Dave B

Exact stuff I have. I'll work on it this weekend. Thanks.

AJA_MAX

Where did you get the CRC maf cleaner?

NmexMAX

iTrader: (22)

Ever been to AutoZone/Checker/Napa?

AJA_MAX

i was checking there site seeing as i have to drive under 2k rpms to drive so i was just making sure

apom

Same problem on my 01. I think it might be the MAF as well.

How does the car idle when started cold? does it stall

Dave B

Yes, he say that there are some driveability problems (stalling, funky idle) when the engine is cold (sitting 8+ hours).

Do you have an intake?

apom

All the problems occured with a WA franken car.. Returned to stock and the stalling issue is gone. It idles around 1200 when cold but once warmed up is better. 4500rpm bog is still present. I hope a new MAF will fix it.

Dave B

Well, last weekend I cleaned the MAF, but the problem still persists. Is a new MAF from Courtesy Nissan really only $110 whereas the 5.5 gen MAF is still $400+. Odd. I may test the coils while I'm at it.

infi35

might be some snesor

NmexMAX

iTrader: (22)

It’s more complicated than that, but in your case, yes, just get a hold of your alias(DAVEB) and he will sell one for you for that price.

His # is in the stickys and scattered around here. I don't know it by memory, but toss a quick search and you should come up with it.

Stop post whoring for 15

aksansai

iTrader: (2)

Took out my 92 GXE's K&N filter that I've had installed for six years to install it into my newly acquired 5th gen ('01). I soaked it in cleaner (K&N) and then re-oiled it (I've done this over and over as I have a K&N in all my vehicles). Lo and behold, I was sitting at a light this morning and the engine just sort of gave up and died. I thought I might have unknowingly let off the clutch too prematurely... but the next light, I had it in neutral with the E-brake set... died the same way. Found out when I got to work today, that I've probably over-applied the oil to the filter and mucked up the MAF. I'm going to pick me up some of the spray and attempt to extract the MAF after work.

perkman87

iTrader: (6)

mafs are like candy in these cars, they just eat em up

Stardust

iTrader: (10)

your posts are getting deleted faster then you can create them

perkman87

iTrader: (6)

it could also be the vais the spring may have cracked, i remeber reading a fix with jb weld somewhere around here

erikgeis

I had a Camaro that bogged down at higher RPM's. I replaced the MAF and the problem disappeared. Not to mention, the gas mileage was a lot better.

antonello104

I have been told that the fule filter in that car is very touchy and can cause high rpm bogge, not to mention the filter in the tank that you cant get to... a fule rail and regulator are also good fixes

NmexMAX

iTrader: (22)

Whoever told you that is incorrect.

aksansai

iTrader: (2)

Same problem with my 01 SE, 5-spd. MAF replacement - tada... all good now!

dc_maxima

MAF!!!!!!!!!

vinco

iTrader: (3)

Would a brand new K&N give the same problem of MAF fouling as a freshly re-oiled one might? I just put a new K&N in my 2K SE about 1K miles ago, and this morning it started acting up on me on the way to work, which is a bit scary, since it's a 64-mile drive to get it home. Suggestions?