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Discussion Starter #1
I posted the following message to the big list and have yet to have any responses.... the same was brought up a long time ago and there was some discussion on it.... I'll post the old email and the new one... new one first:

There was some discussion on this in the past, and someone was trying to compile a list of mods, etc. to try and track down a common pattern of the people that were bothered by this.

For those of you who dont know, these are the symptoms:

While climbing through the RPMS, the rev limiter kicks in, at anywhere from 4000 RPM's to 6000 RPM's. This is with the TRAC fuse pulled.

The problem comes and goes, and, most of the time is very difficult to duplicate.

It happens on my car (Single, 6 speed) mainly when traction is lost, wheel hop occurs, or i downshift (at high RPM's) and punch it very quickly.

The problem first occursed when i was on stock twins (was TTC) - and only seemed to happen on hard downshift.... never manifested itself at the track. Total mods at that time: Air intake, Stillen DP, HKS FCD, Blitz DSBC, ATR exhaust, TTC.

After going single, the problem went away, and _seemed_ to come back when the SAFC was installed. The SAFC appears to be in perfect working order, with all functions working/showing up on the SAFC (throttle, O2, Airflow, etc) We have double checked and triple checked the SAFC and all wires are installed correctly, all other "ECU" mods work great (2 step, SAFC, HKS FCD)

The only "problems" with my car: The cruise rarely works, but sometimes does. And, when pulling codes from the ECU, the only codes that come up are EGR (i have blockoff plate) and Speed Sensor (why the Cruise doesnt work im sure) -- other then that, the car runs like a raped ape.

If anyone has ANY info or have experienced this, PLEASE post.. TIA.
 

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Discussion Starter #2
Here are cut and pastes from the older emails:

Date: Wed, 10 Jan 2001 22:08:20 -0500
From: Keith Fortner <[email protected]>
Reply-To: [email protected]
To: [email protected]
Subject: Re: [mkiv] Hitting rev limiter @ 5K - was New detonation problem

[ The following text is in the "iso-8859-1" character set. ]
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I just got a '95 6-speed and I'm having this same sporadic problem of the
rev limiter kicking in around 5K and it's driving me crazy. Has anybody had
this problem and found a solution? Since the rev limiter is in the ECU is
there anyway to fix it without replacing the ECU? Could it be a bad RPM
signal coming from whatever sensor picks up the revs? Yesterday this
problem put me in a dangerous situation when I was passing a car - I was
accelerating hard and just as I got beside the other car the rev limiter
kicked in and left me w/o the ability to accelerate and a car started coming
in the other lane - I up-shifted into 5th and fortunately had enough pull to
make it around. One time I just stayed on the gas when the limiter kicked
in and it eventualy "turned loose".

Thanks,
Keith
'95 6-speed
'94 TT auto (for sale)

----- Original Message -----
From: "Shane L. Duvall" <[email protected]>
To: <[email protected]>
Sent: Wednesday, January 10, 2001 10:11 PM
Subject: Re: [mkiv] New detonation problem


> Mine would do this when racing, it always happens around this one
> corner
> and when I shift out of the corner into 2nd, it will hit a rev limit
> at about 5000. At first I thought I was dreaming, but it has
> happened multiple times. I thought I had a reason for it but I
> haven't even thought of it since it happened last and this post
> reminded me of it. If I happen to think I my reasoning for this,
> I'll let you know.
>
> Shane L. Duvall
> 94tt 6spd BPU
>

> > On Wed, 10 Jan 2001 [email protected] wrote:
> >
> > | OK guys, here is the problem. Sometimes when I punch it in a low RPM,
the car
> > | will act like it's hitting the rev limiter around 5800-6000. This
doesn't
> > | happen all the time, but most of the time. It also only seams to
happen in
> > | first gear, although I think it may have happened in second gear as
well. I
> > | have just put in some new NGK 3330 plugs, thinking it could be the
problem. I
> > | didn't mess with the gap on the plugs, but maybe I should. I believe
they
> > | come with a .032. I also took the time to check the ohm resistance of
each of
> > | my coil packs and I checked all of my blue boots for cracks. I've run
out of
> > | ideas. If anybody has had a similar experience, please let me know
what was
> > | done to resolve it. Thanks
 

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Discussion Starter #3
| Here's my info:
|
| 95 6-speed, stock ECU, problem is very sporadic, no ECU mods to my
| knowledge - I bought the car used and checked the ECU wiring and everything
| looks stock (I haven't even installed a BCC yet), I've noticed the problem
| in 2nd, 3rd and 4th gears, I am also having a problem with my cruise control
| not working that seems to somehow be related to the odometer/tripometer
| panel - On the rare occasions when the cruise control works if I push the
| tripometer button the cruise control kicks off and the "cruise" light
| flashes. My local Toyota dealer diagnosed that problem as "loss of speed
| sensor signal" and replaced the speed sensor but that didn't fix the
| problem.
|
| Thanks,
| Keith
 
T

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I have the same problem.It used to only do it in 1st gear when slipping the clutch from a roll.It did it when I was stock,and it will do it now that Im BPU+.Tonight,It did it on the interstate in 3rd gear.Id like to confirm what it is.I believe its the sensor that mounts on the inner side of the intake.Mine has puked black crap all over my hoses and I suspect its this piece.I believe its some sort of boost sensor and heard it controls the fuel pump switch-over and other sensors.It has never done it in any gear but 1st in the past and only when I would make it happen,until now that is.If I run my car from a dig,it runs fine.

Joe
 

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Discussion Starter #5
There are 3 possibilities as to what is causing it, in my opinion.


It could be either speed sensor, or the digital odometer... as the speed sensor signal goes through the odo before it gets to the ECU.

One person that was affected (from my previous posts) has resolved the problem by replacing the speed sensor first (didnt fix it) and then the digital odo (did fix it) --- Tracking it down as to which is harder...

speed sensors from jay marks are $160 -- the odo is $360
 

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Discussion Starter #7
BTW,

I did post a "howto" fix this issue, but I cannot find it now.

There was a bad solder on the odometer, and a stereo shopped fixed it very easily. I never could spot the bad solder, but they did.

If you are unsure, you can try this temporarily to see if the problem goes away. If it does, you know its a bad solder in your odometer assembly:


 

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Say that again? So I take the odometer out, and jump those pins? Is it the 2nd and 3rd one from the left in the upper row?

What do I do, just jump then, and try and see if the cruise works?
 

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The need for speed
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I've had this same problem. It happened once when I downshifted real quick... It also happened when accelerating from a stop. I have a video if you want to check it out: http://mavbsd.rh.rit.edu/supra/video/accel.wmv
When the rev limiter went off, I was only at 5800-6000rpm.

Since I put my single on, I've only had the problem happen once to me. I put an AEM in recently and I'll see if the problem comes up again...

Mike
 

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Thank you!!!!!!!!!!!!!:D :bigthumb:

I was just able to fix my Cruise Control. :D without getting a headache from the manual.

TO:michaelvanle

Yes just jump the spots in the diagram. in the ODO plug
thats it!!!!! and go for a test drive.

Once again Thanks

:hail::hail::hail:
 

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NCSUpra said:
Thank you!!!!!!!!!!!!!:D :bigthumb:

I was just able to fix my Cruise Control. :D without getting a headache from the manual.

TO:michaelvanle

Yes just jump the spots in the diagram. in the ODO plug
thats it!!!!! and go for a test drive.

Once again Thanks

:hail::hail::hail:

Well how were you able to fix it? And what was the problem?
 

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i was in temp ttc, and I was told by going permanent ttc, it would fix it....

well... it still does it :(.. im going to try jumping the pins... but doesn't that mean the odo. harness wont go back in?

Edit: I was thinking it was the speedometer... but still... same problem, won't this mean that it won't go back in?
 

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EchoDeDupra
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damn it i thought i was hte only one who had ever had this problem because im a swap...recently it hasnt happened to me but it would only do it in first and second at around 4 grand i thought it was somehting about the fact i have a 4.08 rear end and accel through first and second quite quickly any body have a definative answer yet?
 

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i have the same problem with my cruise control. the little green light comes on, but it doesnt set. i found the tech article on mkiv.com and i tried, but i got a result that wasnt listed.

the cruise light flashes 4x per second showing a 'normal' code/operation. but when i do this, the abs light blinks 4 times and repeats. i didnt see anything mentioned about that part of it.

also, i have tried all the stuff that was listed here.... resoldering the connections, jumping the odo wires, etc.

any ideas? i really miss my cruise on the long trips
 

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i had this problem for like 2 years and i had boost issues with my stock twins not smoothly transitioning...jumping these twi wires fixed all my problems.now car boosts and runs like a champ

Ant
 
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