I picked up a 2004 Silverado a while back and have been slowly getting it sorted out... It is a 260k mile farm truck, so its been neglected for a while. I have too many spare Silverado parts so I figured I should start learning this HPtuners stuff in case I decide to try any swap/cam stuff in the future. So, I have no idea what I'm doing yet and this stock 4.8 is my learning platform...
That said, I've learned quite a bit from reading on here but results for "0v TPS" searches haven't helped as much as usual. I took the truck to town this morning, so the attached log is cold start, warm up, normal drive... no WOT, etc.
(Besides the corrections on what I should be logging and units of measure... currently shotgun blast method.) My question is, where should I look next? So far I have gotten rid of all codes successfully, still sluggish/gutlless. but I did have P0172 and p0175 pop on the drive prior to this log that is still illuminated.
When I first got this MPVI3, I was replacing a lot of parts so I didn't pay much attention to the new TPS sensor not correcting the 0v, I assumed I was using the scanner/log wrong. But I'm going to fix the exhaust this weekend (passenger manifold at firewall, like every other GM on the road..) and figured if I'm going to be crammed in there cussing anyway, could bad grounds somewhere be the TPS voltage problem?
Been able to keep my own stuff on the road for years, just been a holdout on joining the technology side... I'm going to need help to get an understanding of this software...
Anyone have experience with a running driving DBW TPS that shows 0v the whole drive? My other stuff is cable driven so I?m lost on this.. Any input is appreciated!
As a tech, I have found replacement DBW throttle bodies with all white wires (Autozone/Oreilly/Etc) with wires in the wrong locations. Are you getting strange IAT readings too? Just a thought, if its an aftermarket TB.
It was a bolt on sensor replacement. I got 5v at ?e? and ?h? so I didn?t use the connector that came with it. I?m no electrical guru, so I didn?t think about all the various things it could be besides the sensor itself? (also, the probes on my multimeter are kinda big and blunt, so I just grounded to the exhaust manifold when I got the 5v reading.).
I was hoping by trying to learn the HPtuner logs, it would make troubleshooting easier, but at the moment it is a bit overwhelming with all the info slapping me in the face?
Your Throttle Position PID is changing like it should, there is no problem here with the vehicle/wiring/components. These DBW throttle bodies do not use one TPS, they use two. I think you just have the wrong channel. Look for TP1 volts & TP2 volts, may be called something else, but there are two separate sensors if you're looking for the actual voltages for whatever reason. Unless you have some specific need for these individual voltages which I don't think would really be useful, just ignore the voltage(s) and use the normal DBW PIDs.
And don't use the (SAE) PIDs for GM electronic throttle stuff, those give wonky data and aren't what the PCM and its tables are using. The PCM is seeing it from 0% to 100%, while the SAE numbers top out at 84.something.
I?m just trying to narrow down all the issues and see what I actually fix. This thing is really sluggish until about 2800rpm. I can?t verify a vacuum leak, but I?m going to change intake gaskets while I fix the broken exh manifold bolts this weekend.. Just trying to make sure the mechanical and electrical faults are fixed before I mess with learning anything about the tune. Figure that should make it a bit easier 🤣
The reason for all the various PIDs on the log is trying to figure out what everything is. Thanks for the heads up, I?ll try to avoid the SAE stuff, and narrow it down to the needed info as I figure out what PID tells me what I?m looking for.
I?m much more comfortable with a flat blade screwdriver and a quadrajet.🤦*♂️. So I appreciate the help!
Throttle is working like it should so you can move on to looking at other things.
Posting the tune file always helps with interpreting a log file, and vice versa. These trucks are pretty neutered when it comes to spark (sometimes) and power enrichment (always).
Thanks for the reassurance on the TPS. I?ll knock out some more of the known issues and start a new thread when I start messing with the torque mngmt and will read up on PE, so I?m not completely lost with any help I get then. When I had the trans rebuilt, the trans guy adjusted some stuff, but other than that everything I?ve adjusted besides tire size, I?ve reminded myself that it should be mechanically right first and put back to the stock setting so I don?t wind up confusing myself more.
Thanks guys, I?ll be back with questions in a week or so!
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