Performance

[pwerwgn]

I have a 2000 Z71 and runs good but gets terrible mileage ,it came out of California and has all the pollution stuff on it how can I get it running good

 

[OBSandaNNBS]

That is a really nice truck. And rare.

I'm not sure the Cali crap is your problem just yet. There was a time it ran well with decent mileage. Keep in mind 12 MPG for these things is doing well.

What are the symptoms?

You say "runs good but terrible mileage" but then you say "how can I get it running good" sooo...which is it?

Also, any recent work?
Any major work ever?
Miles on the truck?
Acting like this for a long time or short time?

Lots of knowledge on this forum but we need info to help you

 

[Marky Dissod]

I have a 2000 Z71 and runs good but gets terrible mileage.
it came out of California and has all the pollution stuff on it how can I get it running good

Only 2 mods can possibly improve both MpGs AND performance (depending on your foot):
Axle gearS (Z71 = 4WD, yes?) You want 3.73 axles to balance MpG & performance
pcm tune

No point in deleting the cats, but the exhaust system can be improved, although this will not help MpG,
but it will improve performance.

 

[Joseph Garcia]

What is your current city and highway mpg's?

I would first start with a complete analysis with a quality bi-directional scanner to see if something abnormal is occurring. Then, I'd get a typical tune-up for any parts that have been extended beyond their useful life.

Then, take another look at performance and fuel consumption, and see if it has changed.

 

[Eman85]

Blame CA, by 2000 I believe all of the emissions equipment was the same whether CA vehicle or not but we have to hate what we don't understand.
You're pushing a heavy brick with 2 drive axles down the road, don't expect any kind of MPG you can brag about.
How many miles on the vehicle? Did you do a compression test?

 

[OBSandaNNBS]

Blame CA, by 2000 I believe all of the emissions equipment was the same whether CA vehicle or not

This is precisely because of CA legislation...not saying bad/good either way, but the OEMs change the whole fleet to not lose access to the huge CA market.