What did you do to your OBS GMT400 Tahoe/Yukon Today?

[east302]

Need to check it with a scanner, look for the coolant temp sensor (ECT) reading. The temp gauges on these are pretty much decorative. Most 400s seem to run about halfway between the low reading and the center reading.

I’d bet that you’re fine.

Nice Tahoe by the way.

 

[96-2D-Hoe]

I’d bet that you’re fine.

At least it crept up to 160 and stayed there, unlike the previous one. I also drove around for 20-30 mins and it didn't change at all.

I still feel like I'm down on power. I am pinging a little once in a while on the throttle going uphill and that could be the low (54PSI) fuel pump pressure / lean fuel air ratio.

I also often feel like my timing is out. Thought this for many years. Just doesn't seem to be firing right.

 

[east302]

At least it crept up to 160 and stayed there, unlike the previous one. I also drove around for 20-30 mins and it didn't change at all.

I still feel like I'm down on power. I am pinging a little once in a while on the throttle going uphill and that could be the low (54PSI) fuel pump pressure / lean fuel air ratio.

I also often feel like my timing is out. Thought this for many years. Just doesn't seem to be firing right.

Any codes or misfire counts?

 

[PG01]

At least it crept up to 160 and stayed there, unlike the previous one. I also drove around for 20-30 mins and it didn't change at all.

I still feel like I'm down on power. I am pinging a little once in a while on the throttle going uphill and that could be the low (54PSI) fuel pump pressure / lean fuel air ratio.

I also often feel like my timing is out. Thought this for many years. Just doesn't seem to be firing right.

I used to set timing like that, years upon years ago.... gun it up a hill and retard until no more pinging... bad gas will do it too.... no power, pinging...

 

[96-2D-Hoe]

Any codes or misfire counts?

Not bad, just seems off, and I can be fussy. Never misfires. I haven't checked for codes but I doubt there are any. I have a bluetooth gismo that a friend gave me I can check with. Smog test is due with registration in Sept so I've been meaning to take a look anyway.

 

[96-2D-Hoe]

bad gas will do it too.... no power, pinging...

I am guilty of buying cheap gas. But I can get as low as 6MPG without trying too hard

 

[96-2D-Hoe]

Washed, polished and waxed. The old girl has a few battle scars but still has good paint.

 

[east302]

.

 

[TheAutumnWind]

Just changed my thermostat as I didn't like the way it was operating. Would hit 200-210 depending on how I was driving, and then drop down to 170-180 and stay there. I had replaced the original with an aftermarket about 5 years ago along with an aluminum 3 pass rad, water pump etc. I decided to get a OEM Delco rated at 198 supposedly. But now operating temp on my gauge with the new 198 stat is showing 160. At least it seems to be steady at 160. But now I'm really confused. Pretty obvious the gauge is out but... Is this one bad? Was I way too hot before? It's not what I was expecting to happen.

Until you double check the gauge there is no way to know

 

[96-2D-Hoe]

I drove it 80-90 miles round trip along the coast / PCH to the dog beach, Leo Carillo. Such a pleasure to drive now, especially as rear brakes have no screeching, pulsing, locking up at a stop. Purred , and raced, along like a champ. Gave the trans a workout going up a couple hills and everything was working nicely. I also put slightly better gas in and I noticed no pinging, but the windows and the rear hatch were open all the way so I might not have heard it.

One thing I did notice yesterday that I can't say I ever noticed before in almost 20 years was while traveling in very slow moving traffic the truck would idle at 700-800 RPM and keep me moving along, when I stop it drops to 600 RPM. Never, ever seen or noticed that before despite sitting in plenty of traffic.

PS.
I stuck two Delco cooling system seal tabs in before I left as I've replaced a lot of coolant lately and I'm pretty sure it helps stop the intake manifold leak too much.