What did you do to your NBS GMT800 Tahoe/Yukon Today?

[viven44]

Did you change it because you were having issues? Mine was so clogged, going uphill, or even a slight incline would make it stall from all the sediment that had accumulated in it.

No issues on this Yukon. I bought this Yukon 2 weeks ago with only 89K miles and it still had the original factory filter. Figured it was about time the filter was changed.... (since the pump has to work harder to push through a restriction...) on my old trucks I have an in-line fuel pressure gauge going to the carburetor so I can always keep an eye on the fuel pressure which is roughly indicative of the health of the filter and pump.... If there is a known mod on the GMT800 vehicles to install a fuel pressure gauge I'd love to install one...

 

[Tonyrodz]

No issues on this Yukon. I bought this Yukon 2 weeks ago with only 89K miles and it still had the original factory filter. Figured it was about time the filter was changed.... (since the pump has to work harder to push through a restriction...) on my old trucks I have an in-line fuel pressure gauge going to the carburetor so I can always keep an eye on the fuel pressure which was roughly indicative of the health of the filter and pump.... If there is a known mod on the GMT800 vehicles to install a fuel pressure gauge I'd love to install one...

I never looked to add one, but I'd think in the line going to the fuel rail, just before the injectors would work fine. Just a guess tho.

 

[viven44]

I never looked to add one, but I'd think in the line going to the fuel rail, just before the injectors would work fine. Just a guess tho.

I'll need to check that location...

It may be a tight fit but even the line coming off the regulator may not be a bad place either... but then I worry about leaks so it has to be a good job. The fuel pressure is an order of magnitude higher than what I'm used to !!

2002 may be too old but maybe fuel pressure reading it is recorded somewhere.... may just be a good idea to baseline fuel pressure with the scan tool and keep an eye on it.

 

[Tonyrodz]

I'll need to check that location...

It may be a tight fit but even the line coming off the regulator may not be a bad place either... but then I worry about leaks so it has to be a good job. The fuel pressure is an order of magnitude higher than what I'm used to !!

2002 may be too old but maybe fuel pressure reading it is recorded somewhere.... may just be a good idea to baseline fuel pressure with the scan tool and keep an eye on it.

I'm not sure about other scanners, but I can see my fuel pressure when I'm using my Tech2 on my 03. What kind of scanner do you have?

 

[viven44]

I'm not sure about other scanners, but I can see my fuel pressure when I'm using my Tech2 on my 03. What kind of scanner do you have?

I have a Thinktool Pros (2020 Vintage).. it has a lot of bi-directional capability and module/key programming capability. It usually tracks the capabilities of the OE scan suite closely... good to know Tech2 can see fuel pressure...

 

[Fless]

I'm not sure about other scanners, but I can see my fuel pressure when I'm using my Tech2 on my 03. What kind of scanner do you have?

Are you certain of that? I couldn't find a fuel pressure reading on my '04 with the Tech 2, and I don't think my Autel shows it either.

 

[Tonyrodz]

Are you certain of that? I couldn't find a fuel pressure reading on my '04 with the Tech 2, and I don't think my Autel shows it either.

I'm pretty sure i saw it. @Doubeleive might know for sure.

 

[strutaeng]

I've never seen fuel pressure either on my GMT800s on my scanners, but I don't have a Tech2.

I thought fuel pressure data was a GMT900+ thing related to the fuel pump module?

 

[Tonyrodz]

I've never seen fuel pressure either on my GMT800s on my scanners, but I don't have a Tech2.

I thought fuel pressure data was a GMT900+ thing related to the fuel pump module?

I could be wrong. It's been awhile since I've used it.

 

[Doubeleive]

Are you certain of that? I couldn't find a fuel pressure reading on my '04 with the Tech 2, and I don't think my Autel shows it either.

should be there under engine data, and/or fpcm
I don't have a 800 handy anymore to verify
according to 1st gen diesel thread from 2004 you can even increase the fuel pressure up to 25% for testing purposes

https://www.dieselplace.com/threads/fuel-pressure-with-a-tech-ii.5909/

 

[viven44]

These are all the modules I can see. Under engine data there was misfire, fuel trim, EVAP, I/M readiness data streams none of which showed fuel pressure (or engine oil pressure which I was interested to find).

 

[Doubeleive]

These are all the modules I can see. Under engine data there was misfire, fuel trim, EVAP, I/M readiness data streams none of which showed fuel pressure (or engine oil pressure which I was interested to find).


View attachment 439315

that must be a low end scanner if it cant show you ENGINE data, all you are looking at there is topology
dig a little deeper in "powertrain"

 

[Fless]

I challenge anyone to find a working fuel pressure PID in a GMT800.

No FPCM in one of these.

 

[Doubeleive]

I challenge anyone to find a working fuel pressure PID in a GMT800.

No FPCM in one of these.

do not know if these will work but worth a try

• PID 0200: Fuel Pressure (Absolute)
• PID 0201: Fuel Pressure (Gauge)

 

[Doubeleive]

OBD-II PIDs - Wikipedia

en.wikipedia.org

 

[viven44]

that must be a low end scanner if it cant show you ENGINE data, all you are looking at there is topology
dig a little deeper in "powertrain"

Yes I was just showing the topology to show what modules exists. There is no FPCM.

If I go into the powertrain module, I can look at livestream data for probably 500+ parameters (all under various sub-categories like fuel trim, evap, misfire, etc)... which I have already done. I just can't see anything on fuel pressure or oil pressure...

It is probably a mid-end scan tool. I have programmed ABS modules, and other similar modules for 2010 vintage vehicles. Programmed keys for vehicles up to 2016 year model (it can probably handle all functions up to 2020 year model). I can tell already it won't recognize our 2024 Suburban, so I was disappointed. Probably need to pay for a software update.

 

[Fless]

Yes I was just showing the topology to show what modules exists. There is no FPCM.

If I go into the powertrain module, I can look at livestream data for probably 500+ parameters... which I have already done. I just can't see anything on fuel pressure or fuel trim.

It is probably a mid-end scan tool. I have programmed ABS modules, and other similar modules for 2010 vintage vehicles. Programmed keys for vehicles up to 2016 year model (it can probably handle all functions up to 2020 year model). I can tell already it won't recognize our 2024 Suburban, so I was disappointed. Probably need to pay for a software update.

It's not the scan tool. GMT800s don't have an active fuel pressure PID. Gotta measure it at the fuel rail with a gauge.

 

[viven44]

It's not the scan tool. GMT800s don't have an active fuel pressure PID. Gotta measure it at the fuel rail with a gauge.

Yep! I sort of guessed that as I was tracing the fuel lines later yesterday. Of the little bit I saw (line from tank, to pressure regulator, out from regulator, I was hoping to find a pressure gauge of some kind.... was basically looking for wires to/from..)

 

[viven44]

Sent off the Kelsey Hayes ABS module for a rebuild. Has the C0265 (Electronic Brake Control Module (EBCM) Motor Relay Circuit) code that showed up occasionally...I tried cleaning grounds but didn't help.

Last time I tried to do it on a Ford, it was a complete mess as the internal wirebonds had to be reworked.. so I ended up getting a junkyard module and reprogramming it.... The GM ones seem to be a lot easier to fix... just resoldering a few pads... but this time for $100 I'm going to trust someone who has done this hundreds of times take care of it...

 

[latvius]

Designed, installed and 3d printed a new belt routing decal. A replacement one from GM is $25 USD, that's crazy for a sticker. So I designed my own and made it not in French, not for 4 types of engines, made it the match the size of the spot and added a little bling to it. Plus if I can't see I can still feel the route of the belt.
I need a better camera, the color is red not orange but you get the gist.

https://duttonhorsetradingco.etsy.com/listing/1788084396/gm-belt-routing-decal-pn-12575049