Why is my 2jz-gte hitting rev limiter?

[PlacentaJuan]

Since i have got the 2j on the road, i have noticed 2 problems with the engine.

the first is hitting boost cut. 3.5" exhaust and no y-pipe i was expecting it, but it was obvious when boost cut was hit; engine check light comes on, and the revs drop all the was down; completer power lost. (have installed a restricor plate and this problem is now 'solved')

the second thing i thought was a different 'type' of boost cut, but now i think it the rev limiter for a few reasons; firstly because mos said he got the same thing with his 2jz.

secondly becuase it is different than hitting the boost cut; no engine check light and power isnt lost, only the revs 'bounce' up and down and car jerks all over the place.

now if this IS the rev limiter, how is it activating with an automatice transmission?

the 1jz never ever hit the rev limiter and i didnt think it was possible unless you did something stupid with a manual tranny.

can this be fixed any way?

it MOSTLY happens when launching from a standing start with my foot flat, but sometimes it doesnt!!

any help pleeease!!!

[Enchanter]

So what is it reving to when this happens ?
It shouldnt be jerking the car around the place even with the rev limiter though, it sounds like a different problem to me.

[Norbie]

The 2JZ has a "hard" limiter so it certainly does jerk the car around when it hits.

It should be quite easy to tell if it's the rev limiter though, just look at the tacho! From memory the limiter is set at 7000.

As for fixing it, it's obviously a problem with the transmission (ie it SHOULD be changing gears well before the rev limiter cuts in), but that's an area I know nothing about.

[PlacentaJuan]

oh yea, forgot to mention that the tacho isnt working yet... lol

mos is still builing the tacho booster, so i guess i will need some tacho action before i start to guess.

mind you it doenst really sound or feel like the engine is revving out when it hits, but ill wait until i have the tacho.

thanks guys.

[ProjectSleeper]

Yep, Same deal with mine... was a serious pain in the arse to diagnose...

It only used to happen at 100% throttle.. - is yours the same as this ??
or,
Is it doing this between gear changes ?? (ie, Transmission is slipping / flaring and not changing quick enough, hence hitting redline)

[PlacentaJuan]

i got to get out there and drive it some more, (with tacho) but it seems to happen more on a rolling start at full throttle, even if im rolling at only 10k's or so.

doasnt happen much (if at all) from a standing start.

southo what did you do to fix yours?

[ProjectSleeper]

Edit..
we are posting at the same time,

OK, to fix my prob..

1. the only happening at 100% throttle problem (it was ok at almost full throttle (ie, 90% to 95% at a guess)

Also note, this was after the Fuel Cut Defender and Electronic Boost Controller were installed. prior to these being installed, the issue was boost cut only whuch was cured by the FCD etc

these are the steps we took (and big thanks to Dale from Castle Hill Exhaust / Braidedlines.com for his paitience and tuning skills to NOT kill my engine !!)

a) removed and replaced the spark plugs, making sure they were gapped to 8mm (from memory) - still did it...

b) installed the SARD rising rate Fuel Pressure Regulator (ie, to allow extra fuel to mix with the extra boost that the FCD was not allowing the ECU to see) - still did it...

c) Call Mos.

d) recalibrated the TPS again (thinking it was showing over 100% throttle) - still did it..

e) Call Mos

f) Reset ECU, double check AFR's, remove plugs, re-gap to 7mm, replace plugs - still dit it

g) Cry, Pull Hair out, Cry more, Call Mos

h) Use small value (can check if needed) resistor on TPS to "trick" the ECU into only seeing 95% (or thereabouts) throttle ...

YAAAAYYYYY FIXED IT !!!

i) went to Call Mos to give the good news... LOL, he had turned his phone off - Smart Boy !! )

[PlacentaJuan]

ahh the resistor thingie!!

more info your be helpful pls southo like the alue and where exactly it was installed....

[EldarO]

my 7MGTE hits limiter like a whore, the only difference is, that it doesnt jerk the car around, because the torque converter is getting a bit aged, and, it only does it at 100% throttle, not 95-98% or so.

i think the difference is, that while mine is the transmission slipping, and basically free revving, your transmission is still engaged (thats why the cars jumping around), so its most likely wiring or something along those lines.

Eldar.O.

[ProjectSleeper]

it's installed in one of the wire coming from the TPS ( Mos should know, mine is all taped up and I can't see)

as for the value, I will check the colours when I can, and let you know, but I rekon that as long as you go about 5% of the throttle, then it should be fine..

Anyway, I will pull off some of the tape and let you know what I can..