redmaroz

iTrader: (4)

So I actually got to take the car for a spin for the 1st time tonight and it was awesome. The only issue I noticed is my speedometer is not working? I swapped a t56 along with the ls and wired the vss from the ecm. I also removed cruise control from the car. When I installed the pedals for the transmission I just put the brake switch back in and didn't use the cruise control switch that when in the pedals, would that cause the speedo not to work if it is not plugged back in. I searched around and couldn't find an answer to that one. Any help is appreciated.


Thanks,
Jay

redmaroz

iTrader: (4)

So I went back and double checked my wiring for the speedo. I have r50 from the ecm going to pin d on the c207, and the vss for the transmission is pinned correctly also. Im going to double check hooking the cruise switch back up on the pedals and see if that works, just ran out of time. Im just not sure what else it is at this point.

QwkTrip

iTrader: (22)

My '89 would be R50 to C207 pin K.
And then jump C and F at the buffer box.

redmaroz

iTrader: (4)

The car is a 92 and was orginally a tpi car so i do not have the buffer box as far as im aware. Thanks for the reply though, Im going to try and hook up hp tuners tonight or tomorrow and see if maybe i have a bad vss.

redmaroz

iTrader: (4)

So today I changed the vss sensor on the t56 and still nothing. Im going to look again later to see if maybe the vss wires at the pigtail are not bassackwards. Is there something else I may be missing? Am I suppose to change anything in the ecm to work? The 0411 ecm and harness came from an 01 t56 bird.

R13_Braz

My car is also a 92, but TBI. Originally 305/T5. I've got a buffer box. I don't know if it's different for the TPI, but I can't imagine why it would be different because of the injection style.

redmaroz

iTrader: (4)

Yeah it was a 305 tpi previously but tpi cars didn't come with buffer boxes. Im going to give hp tuners a try and see if the values are correct. Thanks

redmaroz

iTrader: (4)

Ok so I am at a total loss right now. I double checked all the wiring from the ecm to the c207, and the wiring to the vss itself. I even tried jumping the vss like suggested in some older threads and its still not working. The speedometer will move just a bit when I first turn the key. I have even replaced the vss. What are the perimeters supposed to be for the vss in hp tuners? I thought the stock 4th gen settings would work, then I read change it to 4000 pmm which I tried both and still nothing. Any help is appreciated, everything else is fine except for the speedo. what are the chances the vss pigtail is bad, or how would I even check to see if its bad?


Thanks.

86White_T/A305

Going back to my first ls swap and doing the wiring. The vss from the trans was directly wired to the ecm,and then the ecm speedo output wire I connected directly to my speedo wire at the cluster.The tune has to be corrected as you mentioned for a 4000ppm and should work.You dont need to connect cruise control to have a working speedo.I have my cruise control wires tucked away incase I decide to add a 4thgen cruise setup later on.

Jaysz28

iTrader: (30)

It sounds like you have HP tuners or the like. Hook up the laptop and do some datalogging. If it shows you the mph you are going, then the vss is working.

or if your PC is unable to go for a ride, take a simple test light, back probe the speedo output wire at the connector and go for a short drive. If the light pulses, then you have a working vss and the PCM is sending a signal to the speedo......

Or, you could put the rear axle on jack stands and do all of this while stationary in the driveway/garage if need be.

redmaroz

iTrader: (4)

Thanks for the replies, yeah i took it around the block today using the hp tuners scanner. the gauge display on hp tuners was showing the tac etc. working, but just registered 0 on the speedo gauge the same as the cars gauge was showing. I replaced the vss on the transmission. Any thoughts as to what would cause the vss not to work? I think i may try using a new pigtail and run new wires from the ecm to the vss. And as far as changing the settings in hp tuners, the factory setting shows 47020 under genveral vss pulses per mile in the speedometer section, is that what i change to 4000 or is it something different? I set the gear and tire size, but was not a 100% on the ppm. Thanks again for the help, I appreciate it.

redmaroz

iTrader: (4)

Ok so good news first, figured out what was wrong, the wires and or vss pigtail were bad. Changed those, but using hp tuners scanner, it shows 20-30mph faster than the speedo. At one point hp said I was going 100 when I know I was not. I adjusted the gears, and tire heighth for what I have. Not too sure how to adjust from here. Any hp pros let me know. And thanks again for everyones help.

Jay

redmaroz

iTrader: (4)

Here are some pictures of the car since I haven't posted any. Not quite done yet, still have to clean up under the hood and wash the 5 months of garage off it lol.

Alice89

iTrader: (6)

Wow, that looks sweet!

redmaroz

iTrader: (4)

Thanks I appreciate its not perfect, but its not a show car either.

Jaysz28

iTrader: (30)

Great looking car! Makes me miss my 91 z28....

so I checked my speedo settings in HPT and this is what I have..... use at your own risk.

General VSS pulses per

Mile - 49,764
Rev-Trans - 17.0000

VSS Output pulses per

Mile - 4000
Mile ABS - 128,000

Final drive Ratio

Ratio - 3.73
Trans revolutions/mile - 852.2460

I hope that helps

good luck with it!

redmaroz

iTrader: (4)

Awesome thanks, I will give that a shot. I know I changed one of them wrong last night when it kept acting like I was hitting the rev limiter lol. Made it to the neighbors turned around and made it back home. Got to love running open manifolds :-) luckily I live in the country. I drop it off to get the exhaust done today.

Jaysz28

iTrader: (30)

Just let us know if any of those settings worked for you

-jason

redmaroz

iTrader: (4)

So the gauge itself is still off, but what is confusing me is the dashboard on hp tuners is showing im doing
90 when the gauge reads 30 or 40....the gauge on hp tuners is really erratic, I thought I switched it from kph to mph lol...ill look again after I get
It back from the exhaust shop. Thanks.

Jaysz28

iTrader: (30)

what do you have entered as your final drive ratio???

jbenge

iTrader: (2)

Looks great, our cars could almost be twins. It's rare to see any decent thirdgens in the area and especially rare to see a 91-92 Z28.

redmaroz

iTrader: (4)

2.73 which is the gear I have, unless it was changed at some point. Thanks jbenge, its not perfect but I agree there are not many good 3rd gens around here, well except the sickness. He lives around the corner from me lol so that makes my car look bad, haha.

redmaroz

iTrader: (4)

Well the exhaust is done, it sounds pretty nasty. Ill get some more pics of it from the rear, I was to excited about starting it and forgot to get more lol.

Pocket

iTrader: (24)

C207 pin D is correct for 90-92 V6/TPIs

FWIW, the VSS wires for LT1/LSx are non-polar so it doesnt affect anything if they're reversed

redmaroz

iTrader: (4)

So like i said before the speedometer is working, but its off. Hp tuners and my speedomoter are both reading the same thing, but per gps its off anywhere from 5-10mph. Maybe even more at higher speeds. I have tried changing gears and my tire size in hp tuners but it comes back as an error with tire size even though it will take the gear change. Any suggestions as to how to correct it?

Pocket

iTrader: (24)

http://www.hptuners.com/forum/showth...ghlight=speedo

Give that a shot

redmaroz

iTrader: (4)

Thanks man, I appreciate it.

redmaroz

iTrader: (4)

Just in case anyone has issues in the future, that link does the trick. Speedo is on the spot now. Thanks again eveyone.

Jaysz28

iTrader: (30)

just thought I would copy/paste the fix here for others to find

[quote HPTuners site]
To many pulses per mile will make the speedo read slow, to few will make it read high. The math is simple, take your speedo indicated mph and divide by actual mph. Multiply that value by your pulses per mile and your done. So 65/60=1.083 Multiply this by your ppm which is essentially a 8% increase. As long as your GPS and speedo reading are bang your correction will be too.[/quote HPTuners site]

Jaysz28

iTrader: (30)

just thought I would copy/paste the fix here for others to find