Disable VSS Feedback?

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msaunders
 

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Disable VSS Feedback?

Post by msaunders »

Trying to run without the speed sensor on a S13 KA24DE here.
Just wondering if it is possible to disable the ECU from looking for a speed signal from the VSS?
If not, is it possible to have DTC codes reset on startup or something of the like?
Thanks
Matt
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Re: Disable VSS Feedback?

Post by Matt »

Your best bet is to put a speed sender simulated signal in there. Too many places the ECU checks for this signal otherwise and requires quite a bit of customised code modification

PLMS does the sender units if you cant get a real speed signal into it
msaunders
 

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Re: Disable VSS Feedback?

Post by msaunders »

Thanks for the reply Matt.
The code modification you speak of, would that be inside the bin?
Matt
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Re: Disable VSS Feedback?

Post by Matt »

Yes it would. Would need to replace where the VSS signal is read and change that to a constant speed
Zuikkis
 

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Re: Disable VSS Feedback?

Post by Zuikkis »

I once did a quick and dirty "fix" for the missing speed sensor, simply connected tachometer output to ECU speed sensor input.. :) This worked pretty well. It was CA18DET, though.
Matt
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Re: Disable VSS Feedback?

Post by Matt »

So what does the speed show up as then?!
Zuikkis
 

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Re: Disable VSS Feedback?

Post by Zuikkis »

Matt wrote:So what does the speed show up as then?!
No real values, of course.. But it shows something, which is the point. ECU uses the VSS signal only to judge if the car is stationary or moving, I don't think it matters how fast it's going?

On most cars if speed=0, fuel cut-off at deceleration doesn't work. What's more, if you have VCT that also is disabled while standing still. You can get those working by simply connecting the speed sensor input to tach out..
Matt
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Re: Disable VSS Feedback?

Post by Matt »

okay. i was wondering if km/h was showing and would then do something like speed cut if they got too high
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