Drive by wire 280zx

[BLOZ UP]

I seems like a waste of time an money on these car all the linkage is short and usually has no problems whatsoever. Do you want your Z car taking off on its own like some of the Toyota Prius cars did. I think, keep it simple stupid, applies here. At least if there is something wrong with mechanical linkage you can usually see it and fix. Computer glitches are much harder to deal with and track down.

 

The "electrical gremlins" part of the recall was never proven. It was the floormats and people who don't know what to do in abnormal situations. Computer glitches are really easy to track down when you put in a manufacturer's diagnostic tool. It tells you what's wrong with the car.

 

GM's, and I'm sure every other manufacturer, have like triple backup systems for e-throttles.

[TimZ]

The "electrical gremlins" part of the recall was never proven. It was the floormats and people who don't know what to do in abnormal situations. Computer glitches are really easy to track down when you put in a manufacturer's diagnostic tool. It tells you what's wrong with the car.

 

Floormats? Give me a break. The diagnostic tools you appear to be referring to (OBD scanners, code checkers etc) are only used to diagnose problems that are already known to be potential problems. They generally can't be used to find "glitches" that nobody knew were going to happen.

 

GM's, and I'm sure every other manufacturer, have like triple backup systems for e-throttles.

That's kind of the point - the OEMs (at least the conscientious ones) spend SIGNIFICANTLY more time developing the failsafes for these systems than they do the actual "normal" functions. The failsafes are generally specific to the hardware design and aren't necessarily interchangeable. If you don't understand exactly how the throttle functions and exactly what failsafes are implemented for both software and hardware, then this probably isn't a good idea.

[Pzary3233]

I agree that there is no safety concern when using an e-throttle. UNLESS you install it in a manner that is undafe. You do not use grommets for the wires going through the firewall and you mount the Throttle Control box in a way that it gets large amounts of heat and water on it.

 

With HP Tuners and the like you can make a GM eThrottle 100% more responsive them the OE tune, you can make it linear or non linear, etc, etc.

 

As was pointed out you can have throttle issues with a mechanical or eThrottle.

 

HOWEVER I still preference a cable throttle for my personal car so long as the eThrottle is at the OEM standard with a delayed response. Sometimes my F150 is so far behind it's not funny. Then again it is a Ford...

[TimZ]

I agree that there is no safety concern when using an e-throttle. UNLESS you install it in a manner that is undafe. You do not use grommets for the wires going through the firewall and you mount the Throttle Control box in a way that it gets large amounts of heat and water on it.

 

With HP Tuners and the like you can make a GM eThrottle 100% more responsive them the OE tune, you can make it linear or non linear, etc, etc.

 

No safety concern? How can you say this when you don't even understand what the failure modes are? Grommets and mounting away from heat don't even come close to what needs to be done to make this acceptably safe.

 

Tuning an oem controller that's using an oem e-throttle matched to its application is NOT what we are discussing here, as far as I can tell, and nobody has given me a warm fuzzy feeling that they really appreciate the magnitude or seriousness of the problem here.

 

If you are really dead set on doing this, then you should at a minimum install an emergency kill switch that's easily accessible with a quick hand slap, like this one:

 

...no matter how good a driver you think you are, if this thing fails to WOT, reaching for the key and tuning it off is not a good or fast enough backup plan. I've been doing OEM vehicle development work for 18 years now - I do have some experience with this.

Edited October 5, 2010 by TimZ

[Pzary3233]

If one is using an OEM system I don't understand the problems with it. Is all that I am saying. No you are right I do not understand the trouble codes with the eThrottle stuff... Please explain.

[Pzary3233]

If one is using an OEM system I don't understand the problems with it. Is all that I am saying. No you are right I do not understand the trouble codes with the eThrottle stuff... Please explain.

[randy 77zt]

since timz works in the engineering end of auto manufacturing he would have inside knowledge of the dbw throttle.i worked as a ford dealer tecnhnician for 20 years plus have a 2 year electronics degree.lets say somebody swaps in a chevy lsx dbw motor into a z.they get lazy and dont hook up the brake light switch,speed sensors and other inputs.in a stock oem car if the throttle went wot and the driver hit the brake pedal the ecm would probably shut the car down if it couldnt return the engine back to idle speed.in the car with the engine swap the ecm wouldnt know what was going due to the lack of input sensors and somebody would get a wild ride.the programming in the oem ecm's doesnt operate the dbw throttle blade in a linear response compared to what you are doing to the gas pedal.the gas pedal input to the ecm isnt the only sensor the ecm uses to compute dbw throttle blade angle.the ecm in a modern car does many things you dont know about while you are driving.my work with ford is a good example of non-linear throttle feel-fords fell very soft from a take off.my stepson had a 2001 nissan senta ser-the throttle would spin the tire at low throttle settings to make you think it was a fast car.i use a vipec v44 efi computor to run my z engine.the vipec v88 will operate a dbw throttle body.i have 10 thumbs with software-if i put dbw into my car it would probably never be working correctly-i lose patience with software

[Pzary3233]

Thank you for the insight. I never thought about the brake signal being a player in that scenario.

[HowlerMonkey]

The down side is getting stranded when it fails.

 

This is why toyota had a throttle cable on most of it's drive by wire engines for a few years after they were introduced.......so you could still get 20% throttle if it failed.

 

Straight drive by wire with no other systems affecting throttle would be ok but most every OEM version I have seen spends way too much time interpreting what it thinks you want it to do.

 

Manufacturers have done some strange stuff concerning the actuation as controlled by the ecu such as.......

 

1. opening the throttle more than the amount you are commanding to make the car feel more powerful that it really is.

 

2. Closing the throttle during upshifts to save a weak tranny which allows it to get through warranty period.

 

You should watch scope on the throttle body....it will surprise you what really is going on.

 

 

RE: the toyota thing.

 

There have been no cases that have even made it to court.

 

Toyota is around 12th on the list of "sudden acceleration" complaints based on brand with volvo being number one.

[BLOZ UP]

Floormats? Give me a break. The diagnostic tools you appear to be referring to (OBD scanners, code checkers etc) are only used to diagnose problems that are already known to be potential problems. They generally can't be used to find "glitches" that nobody knew were going to happen.

 

Yes, floormats. You sound like you want to believe it was somehow Toyota's fault. There were no electrical glitches discovered. And, no, I'm not referring to OBD Scanners. I am referring to GM's Tech-II, Nissan's Consult, etc.

 

 

That's kind of the point - the OEMs (at least the conscientious ones) spend SIGNIFICANTLY more time developing the failsafes for these systems than they do the actual "normal" functions. The failsafes are generally specific to the hardware design and aren't necessarily interchangeable. If you don't understand exactly how the throttle functions and exactly what failsafes are implemented for both software and hardware, then this probably isn't a good idea.

 

No disagreement here.

Edited October 29, 2010 by BLOZ UP

[Tony D]

Opening the throttle when coasting isn't "air injection".

 

Actually, if the injectors are shut off, it's EXACTLY what it is! Introducing straight 19% O2 into the exhuast on a straight ride-through the engine with no HC added. It provides post-combustion chamber O2 for combustion in the catalyst or exhaust manifold.