Boosted Performance

iTrader: (14)

Was out doing some street tuning earlier today and the car went in to limp mode after a second gear pull. ST at about 9.5psi of boost, a/f 11.0-11.5:1 tuned via Haltech EMS. 06 350z 40,000 miles, and about 10 of those are boosted.

After that 2nd gear pull (up to 6500rpm) the car would not go past 2000rpm. I was very close to home so I drove it to the garage, turned it off and restarted. I was able to rev it and drive it past 2000rpm, but it idles at about 1000rpm. At times it jump up to about 1300rpm, but comes back down. Pulled the codes:

P1148 Closed Loop, Bank 1
P2101 Electric Throttle Control Function
P0011 Intake Valve Timing Control
P0021 Intake Valve Timing Control
P0153 Front O2 Sensor, Bank 2 Response Monitoring

After this I cleared it all, and the car starts fine, drives ok but the idle is still high and bouncing a bit. Don't know how much driving it takes for the codes to come back.

Some searching tells me that the TB is toast..anybody with similar experience? A/F is fine, all the temperatures are fine…ect all of this was logged through the Haltech.

Dynosty

iTrader: (27)

P2101 is your problem causer. Do you have a FSM to reference for diag? There are a few grounds to check etc before replacing your throttle body.

djamps

iTrader: (1)

That is an unusual combination of codes...

I would check all engine grounds especially the front 2, for a melted harness or other wiring issue such as loose connectors or even water on the ECU.

Boosted Performance

iTrader: (14)

Thanks for the input guys, will jack the car up tonight and check grounds first. I installed some ceramic coated headers, maybe I missed a wire when I tied thing up. I do have the FSM to reference to, and will go on from there.

str8dum1

iTrader: (11)

so the codes didnt come back after you cleared them?

not sure which grounds Hal is referring to, unless you took apart your harness and did some direct grounding. The only free ground wire is for the coil packs (and battery obviously)...

Boosted Performance

iTrader: (14)

The code did not come back, but I only drove around the block and let it idle for about 10 minutes. I am not sure if the ECU has to detect a fault condition for a period of time to throw a code. However, there is still some sort of an issue as the idle is not as it used to be, 1050rpm vs old 650rpm.

The harness was never taken apart, and the grounds "should" be good, as they were never moved or removed.

I had a friend who had these similar symptoms, and it ended up being a ground fault for the TB. He has the Greddy TT kit, and also never did anything to his harness. Go figure.

Boosted Performance

iTrader: (14)

Well, just spent some time out with the car. Yesterday, I disconnected the battery for about 5 minutes, reconnected and left the car over night. I got home today and started the car, it seemed to idle a bit high (900rpm) but no codes.

I proceeded to do a TB reset/calibration, and that went well. Took the car out for a 10 minute drive with a few WOT pulls. The car runs perfect and after the TB calibration idles perfect as well, right at about 650-700rpm.

I did forget to mention one probably important detail in my OP. When I got back home last night, I noticed that my radio was reset, as if the battery power was lost. Maybe there is a bad ground like you guys suggested.

Will have to go through the engine bay and see if I can find something.

The only code that came back was P0153.

aln

Did you try an ecu reset?

Boosted Performance

iTrader: (14)

After I did the TB calibration, there have not been any other issues except fuel.

For some reason my bank two was leaning out (up to 1 point on the a/f log) in the 3500-4000rpm range at WOT. Had to add about 9% of fuel in that area to bank two to make it even with bank one. This is with Haltech EMS.

There rest of the time the two banks are close....not sure what to make of it. I thought it was the way my fuel system was set up, so I changed it to dual feed dual return. Nothing changed.

aln

Had idling and fuel issues on my t5 (5 pot) turned out that a clean and flow match of the injectors sorted that one out for me.

Boosted Performance

iTrader: (14)

Injectors are brand new.

djamps

iTrader: (1)

I had to add a couple percent to one bank on my uprev to get the A/F lined up at WOT. A little variance between banks is pretty normal for the VQ... 8% seems a little drastic tho.

djamps

iTrader: (1)

Do a couple pulls then shut down and read your plugs. In other words, make sure it's not one cylinder running lean.

Boosted Performance

iTrader: (14)

Funny you mention that, as it was on the to do list today :










Looks good (even) to me. These now have about 500 miles on them, including tuning/fuel adjustments. This also includes about 15 WOT 3rd gear pulls in 3rd, all at 10psi of boost.

aln

but have they been flow tested? your plugs look ok (even to me)

Boosted Performance

iTrader: (14)

Yes they have, and are matched to be within 1.5% of each other as far as flow goes. If I was to get real picky, #6 is the leanest out of the bunch, but nothing to worry about. I could take a bit more fuel out of the mix as well, as they are all a bit rich. This however is on the very safe side, and I prefer it that way.

aln

mmm not sure why then ,my haltech threw my std ecu into 'limp' mode when I had a crappy tune on it. After I had the tune sorted it never came back. Think the old map was crappy tuner trying a bit to much. (timing)

Boosted Performance

iTrader: (14)

I have not had any problems with the way the car runs ever since I did the TB calibrations. It runs like a champ. I just don't know why I had to add that much fuel at that load on bank 2. Usually it is bank one that runs leaner do to OEM plenum design.