Thread: only 80-89% at WOT

yea I guess ill do that before buying a new TPS(yes from JET)

Sounds like a plan. Also, the WOT TPS voltage is typically around 4.5-4.7V (or 90-94% throttle open) from what I've seen. Others may have seen higher.

ok im gonna get it looked at from the mechanic at the speed shop I work at... trying to figure things out on my own... good day for him to roll my fenders and put the new exhaust on too I guess

thanks for trying to throw some help at me!

No problem. Good luck.

Originally Posted by Sven The Sexman

Sounds like a plan. Also, the WOT TPS voltage is typically around 4.5-4.7V (or 90-94% throttle open) from what I've seen. Others may have seen higher.

0.40 V is 0% and 4.0 V is 100%.

Everything else doesn't matter.

Rotate the sensor so that you get below 0.40 V at idle, and above 4.0 V at WOT. Check the ground, and check for 5V at the connector.

The other area of concern is, does this device actually read the value correctly?

So in short, check for voltage, not TPS.

Hah, good thing I remembered this little fun thing: http://www.hptuners.com/forum/showth...2069#post32069

In short, it's likely an issue with your data logger not interpreting the PCM data correctly.

Originally Posted by matt5112

In short, it's likely an issue with your data logger not interpreting the PCM data correctly.

His gizmo does not read PCM data...it merely intercepts it via splices.

No wonder he's only seeing 88%, to GM, 4.0 V is 100%.

It doesn't matter what it does, it won't make any more power. You don't make more power with a PCM tune on a 3800. You just play with transmission settings, correct fuel system when you add bigger injectors and that sort of thing.

how do I test the TPS voltage? where do I put the pins?

DMM on the pins, proper scan tool etc.

Pinout might be on the sensor itself, but it's pretty easy to figure out.

Check voltage from ground to each pin. One will be 0V (Ground), one will be 5V (5V supply) and another will be a varying value depending on TPS (TPS signal). Engine doesn't need to be started either. Might be ideal to turn the key to on, and leave the engine off. That way you can test WOT right there in the driveway without bouncing the engine off the rev limiter.

Originally Posted by industrialfish

This is exactly what it does. They work fine on the 3800 Series I, just not on anything with ODBII. Although the JET modules I remember just snapped in between your PCM connectors to modify the signals, no splicing.

They actually still sell those too. I'm not sure what exactly they try to do to the signals, but if I ever find one (for free obviously) I'll plug it into my Z28 just to see the sensor values affected on the scan tool.

Thanks for the info guys.

Are there any write up links for doing a TPS relearn?
also need a write up for the EGR delete.

Google gm tps relearn. You basically floor it turn key on turn key off, off pedal turn key on turn key off. Repeat 4 times

ok looking into it now. thanks

TPS relearn didn't work, so Im guessing its the unit not reading proper... no biggy as that's not what I wanted it for...

another question, when I do the EGR delete do I have to take the entire thing out or do I just take off the top part and put the block off plate there leaving all the hoses and what not hooked up?