89 turbo supra 5 speed dies in mid shift????
 

My supra is dying in the middle of a shift. The idle is good, is doesn't die any other time. It only seems to die when it drops from a higher rpm to a lower one...it just doesn't seem to catch back at idle all the time. No check engine light. Any suggestions?

89 turbo supra 5 speed...
new motor with about 6,000 miles on it.
rebuilt tranny as well...

acutally I just got to looking back at the original post of the problem when it first happened...which happend to be last april.

Im 80% sure that its the BOV due to the fact of all the boost buildup between shifts.

Oh, and it isn't throwing any codes btw.

But, my options....

Get a new BOV, but will that fix the problem? Is the problem that it is releasing the build up air too fast or that it isn't releasing the air like it should?

Bypass valve...

or OEM stuff...which is horrible....

Is it an aftermarket BOV venting to atmosphere? If so, then that's very likely the cause of your problems. It isn't that the air isn't released properly, the problem is that the computer is expecting that air to still be in the system (because of the factory BPV). Since the air isn't there, the engine runs extremely rich during shifts, and this can be enough to stall the engine.

@btwilson...
in my original post last april you were the one who suggested that it was the aftermarket blow off valve...
Question: It is an older type blow off valve not a ssqv.
From what I read, the newer style valves allow for the air not to completely escape unless under extreme load.
So, my question is will a newer style bov help out any?

I don't want to go back to the OEM style, I would rather go with an aftermarket bypass valve.

Also, in the original post I said in my last post that I had reset the computer and I had no problems out of it....until now....
ten months later... which confuses me beyond all belief...

I reset the computer last night and took it out with no luck...

I have a really retarded question too:
If I was to take it too a shop and get them to tune it to where the timing was retarded a little would it make up for the stall?????
The car runs extremely rich in the first place....

ROFL..... you really should stop asking for advice if you're just going to ignore it.

You have a couple options: Ditch the BOV for a BPV. Connect a BOV AND a BPV OR find a dual outlet BPV which will recirc one of the two ports and blow off the other at the same time.... they *help* for half the build and for the other half they don't make a difference... they're pretty hard to find and I think they're pretty expensive. The only other option is to buy a fuel controller with throttle tip-in and tip-out tuning and get the system tuned for it.

Timing isn't going to do shit but cost you more power and has absolutely NOTHING to do with how much fuel the ECU thinks the engine needs. No, newer BOVs do not let out any less or more air than older ones... it depends entirely on how the BOV is tuned (if it's adjustable; a feature even many old ones had). There isn't a design out there that I know of that is so vastly different that I'd believe that line of crap.

@cre...

this is the bov that is on my car

if its adjustable, i don't know how to.

I was wrong in the earlier post it is a ssqv bov, just a older discontinued item.


http://www.streetunit.com/HKS_SSQV_B...1421-sa001.htm

There are spring kits and a re-circ kit available for those. The intent in adjusting a poppet or valve isn't to limit the amount of air that's exiting as that also induces surge (the whole reason for the BOV/BPV to begin with)... The purpose is to set the amount of vacuum required to open the valve. You should get the hardware to tune it OR run it re-circ and get over the "uber cool whistle", IMHO.

By the way, adding a tighter spring or adding a restriction to the reference line (which I didn't discuss) won't fix the problem... they're hacks which will cause another type of problem and just REDUCE the existing one... you'll still spike rich when shifting (which has NOTHING to do with how rich the car runs normally) and you may still run stall periodically. They're just hacks.

With a healthy turbo a LITTLE surge isn't a huge concern and will improve throttle response during a fast, high load shift (see automatic transmission :p )... It's not something you want to expose an old turbo to as much as possible.

"get over the "uber cool whistle", IMHO. "

I think that the uber cool whistle makes the car....
the one thing I enjoy most about the supra is when someone who has a very expensive car with a v8 pulls up beside me at a redlight... I laugh.

and i know that everyone on here can appreciate that.

Im not going to drive it for a while since the kit is just as much as a bypass valve or an offbrand bov. I know it isn't good for it.

And if it is still going to do it with a new spring kit I don't see that being the best idea.

I like putting both the bov and bpv on...

If I was to recirculate...where would i put the other end of the hose?
Cause its a cold air intake with the bov.

It would have to recirculate to the intake hose between the AFM and the turbo.

RANT:
No.... the thing I like about pulling up next to a high dollar car is kicking their ass and it not sounding at all like I'm trying. It gives people chills, says I just won your girlfriend and I've still got more. I've had it done to me by a couple VERY cool (all under the hood) cars and I've done it to some as well. Besides, a large amount of people think nothing good about those who are doing it just for sound (and yes, many of us do know when you come driving up if it's doing you any good or just some stupid ricer punk mod to look more like Mr. Diesel or that blonde guy... or someone from Initial D if that's your thing.... :ghey:). But, to each his own; I'll still help where I care to.
/RANT


Running dual will still leave you running rich at the shifts (and thus still cost you power and throttle response). A dual setup probably isn't your thing anyway as it cuts the volume of the whistle in half. Getting the electronics to live happily with whatever arrangement you're running is the key here and you may also find that there's more power to be had from a good tune; The stock fuel maps are quite conservative and rich.

You really have three choices:
1) IF you're more concerned about actual power and efficiency, tune it.

2) IF you're worried about drive-ability and cost along with power, get the recirculation kit or a BPV and get over your love for Big Bird.

3) IF you really don't give a crap about any of the above other than somewhat decent dive-ability then run a dual setup and be done. It will still bog, possibly stumble, but shouldn't stall.... take your current problem and cut it in half.

I suppose you could install a "bad boy" switch. Install both BOV and BPV Connect a VSV to a PWM and place the VSV on the signal line to the BOV. When you want to act tough flip the switch to turn on the BOV; When you're ready to drive aggressively turn it off and you turn the BOV off, leaving the BPV running solo. (You could also turn off the BOV when a cop gets behind you this way.)

There are other ways to deal with this but the cost just keeps getting higher. The issue lies with both the ECU and AFM (this problem affects both VAFM and KVAFM setups).

I just bought a new bov and recirc kit...

ill let ya know how it goes...

it will probably be the week after next before anything gets here anyway....

Way to cave to the peer pressure... ;) (yes, I know I'm a dick)

Did you look for a recirc kit for your HKS? They're out there.

Are you going to just run recirc or a BOV/BPV combo?

In the end you should still consider saving up for a good fuel controller and some tuning.. you'll be able to run whatever BOV/BPV you like and you should be able to wring a bit more power out of the engine.

First off...I sure as hell aint made out of money and I agree that a 300 dollar tuner would be pretty nice.

The kit that I ordered is an hks kit, but the offbrand bov i bought is exactly the same so i will try em both out and see what works better.
The bov isn't that hard to take apart to put the 1" hose clip on.

Im not going to put a bpv on cause i think that will just be in the way...its already tight as it is...

OH, btw I had probably another stupid question im sure that you could answer...

the vacuum places where the OEM bov circulates....if i was to put a vacuum line there...could that possibly help? Just curious since i have a week to mess around with it.

And one more question...Does it hurt that my exhaust has the wastegate runner and its cut off?

and thanks for admitting your dickishness...
ill admit my stubborn bastardness...lol

I've seen a very high power MKIV with 3 PBV's. ;) When you've got a lot of air to dump, sometimes one just isn't enough.

I don't quite follow.... The You are, I assume, referring to the intake's inlet for the BPV's exhaust or discharge? If so, with a BOV you just want it plugged. When you install the BPV kit the discharge will go there like it was in the stock setup. The vacuum system goes positive when you start boosting, running a hose there will just cause a big boost leak.

Comes with the territory. ;) Some people bring it out in e more than others. No, I'm not referring to you; Someone else has been ticking me off.

I didn't know what that outlet did...
both outlets are plugged for original bov.
i was just curious...

does it hurt that my exhaust has a wastegate runner that is cut off?

and what fuel controller would you recommend?

A BPV/BOV has an inlet and an outlet. The inlet is on the boosted side of the intake, between the turbo and the throttle body. The Outlet side is on the ambient/vacuum side of the intake, before the turbo (and after the air flow meter in certain setups like this one). The poppet/valve is held closed by a spring and depending on the type the spring is assisted by the boost pressure. When you let off the throttle the intake plenum (the portion AFTER the throttle body) pressure goes negative and the manifold reference (the small vacuum line) goes negative sucking the poppet/valve open against the pressure of the spring. The strength of the spring dictates how much vacuum is required to open and keep the valve open. Excess pressure between the turbo and the throttle body is now discharged back to the intake before the turbo. This prevents new air from entering the system and the ECU doesn't add any more extra fuel... you don't run lean though because the ECU has already measured and allocated fuel for the air which has just had its trip extended. If you just dump the air out, the ECU still thinks it's in the system and it still send fuel for it.

Again, I have no idea what you mean.... doesn't sound good though. If you want to control the wastegate then build a ball valve controller for $30. Don't cut anything, don't add any washers and don't weld anything...

It depends on your final goals, how much you're willing to budget for and if you are willing to wait until you can get something really beefy or if you just want something for now. The Apex'i SAFC-II is an older unit but very reliable and very popular; Its successor is the Neo, an equally popular unit and even more flexible and user friendly. Beyond that you're looking at a MAFT Pro setup or a full stand alone EMS.

I follow...
reading always helps...

the hks vpc...is this a good tuner?
and how hard are they usually to install...

maybe i will spend my tax money on one...
taken i get the bov thing fixed when the parts get here...

Im going to take very detailed pics tomorrow of my setup.
I wasn't the person who put the new motor in, so I don't know everything that was changed and what not. I know that the motor was BUILT.

Im looking at the neo it doesn't seem extremely hard to wire and it has alot of good components to it...

I know that this car has alot of potential once I get all the minor kinks worked out.

http://cgi.ebay.com/ebaymotors/86-91...Q5fAccessories

This is the downpipe i have, the second pipe running down is cut off halfway.

The VPC is a decent piece of hardware.... but it is OLD. By today's standards it's the MAFT Pro's handicapped brother who even gets beat up in the back of the short bus. It's great that it allows the removal of the KVAFM in favor of a speed/density setup, but the "one size fits all" pre-tuned ROM and very basic tweaking controls leave a LOT to be desired by today's standards. Honestly, at this point I'd step up to a MAFT Gen II or a MAFT Pro.... or go full standalone... but they're hell to learn in most cases.

Basic fuel controller are very easy to wire up, tuning takes practice and unless you're also installing a wideband you just have a shop do it for you.

You don't want to run that downpipe on the stock turbo unless you've welded in a dividing plate to separate the air spaces. Aftermarket turbos often have the housing cast so that the wastegate and the exducer's air flow is completely divided... not the case on the stock CT-26. Not doing so makes thins louder than they should be as the primary outlet is leaking out there too and it creates even more pressure that the wastegate actuator has to push against in order to open the gate. =

It does not matter that the outlet of the divorced wastegate pipe is open at the end. With a well flowing exhaust thet's just another matter of noise versus stealth... no performance gain, but no loss this time.

EDIT: There's also the MAP ECU. It's a unit comparable to the MAFT Pro... well the second generation of the MAP ECU is. Like the MAFT Pro, it lets you change over to a different type of air metering system (the MAFT Gen II does also but it lacks support for S/D and doesn't have a built in boost control function) and allows you to tune your fueling... I don't know if it offers wideband O2 integration, boost control or timing control. I have't used it, but in some circles it is VERY popular.

after much much much much much research today...
The neo still has my best interest.

what got me was this

"On MAF applications with open-air blowoff valves, there is a deceleration air correction feature that allows the tuner to compensate for the over-rich condition that occurs at throttle-off. By adjusting the MAF signal at throttle-off condition, the tuner can reduce the amount of fuel injected and prevent stalling."

my main issue right now.

The price range on all of the maft tuners are about the same as the neo, and they may have a few more feature than the neo. But I'm looking for something that gets the job done and looks good while doing it and the neo is a perfect example of that.

Features like being able to watch rpm's on the screen?
how badass is that.

I want someone to get in my car and say "nice gps"...and ill be like huh??
that aint gps....thats badass....

this is the link for the apexi neo if anyone else is interested

http://www.apexi-usa.com/products/De...id=5347&v=more

i also plan on doing the t61 upgrade from the ct26. The only part you have to buy along with it is an oil feed line. The stock drain feed will work. (correct if wrong)

The turbo doesn't pull as strong as it should, but holds strong when fully spooling. If i were to guess the hp the supra puts out right now I would guess around 250 or so, with the 1,000 dollars in mods I hope to hit 290 or 300 hp. Which is probably a long shot.

Oh and I went back and cancelled the order for the new offbrand bov, I fully believe the hks is doing what it needs to be doing and with it being recirculated it should be fine.

By the way, I put a couple of pics up on my profile if you want to take a look.

Function over fashion.... perhaps one of these days you'll think more of making power than dick waving.

Pretty dumb since there's a gauge that's easier to read and in line with where you SHOULD be looking when driving. Man, you really bug the piss out of me... but you're nice enough so what the hell.

The MAFT series and the MAP ECU also allow you to switch to a less restrictive air metering system.... OR to DELETE the air flow meter altogether... now that's badass. ;)

If one of my friends ever said that, they'd be walking home. Is there a new breed of stupid down there which just hasn't gotten this far yet?

250? At the crank maybe... you have no mods that are any significant power adders. If you'd read up more and take more time you should be able to get a lot more out of your car for that amount of money... of course that depends on how healthy your engine is. Fix that downpipe too.

People around here don't know alot about cars, I can tell you that much right now.

I do like that everyone comes to me with questions though...its quite sad that almost everything you need to know about cars you can find on the internet...all you have to do is read. (people are lazy, and I am too from time to time)

The performance rebuild kit that was put in the engine was rated at 260hp(with turbo at 4500rpm's) that is with .060 bore and a real nice set up on the twin cams and pistons, I don't think the crank was anything special. I DON'T believe its hitting anywhere close to that. It takes 7 seconds for a 0-60.

The engine is very healthy and can handle everything I throw at it.
(The exhaust has a divider welded on the turbo end)

I think I like "badass digital tach" over function cause im still young.
But the functions are close to being the same on all of the tuners, thats why there is so much competition over the items...
And the neo is a little easier to install in my personal opinion.
Now learning how to adjust things on it...thats another story.

For those who have been following this thread and may have similar problem. I ended up putting octane booster in the gas (routine for me) and the car still stalled, but did not die. I also ended up putting premium instead of mid-grade in this time, so I'm sure the combo had a big thing to do with it helping out.

I'm going to see if this will make any difference in a longer term and post my results back at a later time. :)

If this doesn't help your situation, revert back to previous suggestions.

Thanks!

Be aware that the higher the octane the less power you make per unit of fuel. Higher octane fuel has mush lower kenetic energy and once you go beyond the ECU's ability to increase spark advance you lose both power and mileage.

I have no idea how that would fix your stall issue from a vented BOV... should choke up the engine just as much... You may have been experiencing an additional over-rich condition due to pinging which combined with the over-rich condition from the vented BOV.