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Lack of power?

04lss

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04lss Enthusiast

04lss

Posted
Posted

Hi All,

 

I will preface this by saying I am fairly used to fast cars. My next slowest car to the tahoe is a 2004 regal GS with an intercooler e85 and high ratio rockers. Then I have 2019 mustang and so on. Most cars feel slow to me. 

 

When driving the tahoe ive noticed it has a really good response from a stop. The first bit of throttle makes the truck jump. What ive noticed after that is once the throttle hits say 40% there is nothing else. I can push the throttle feel the power increase and then it is just flat. It doesnt seem to gain power as the RPM increases either Is this normal? It seems like peek power is around 2-3k rpm and it just flatens after that. It also is really really slow. Im afraid to pull out in traffic with it even when there is a good ammount of time. 

 

There are 3 things i am aware of. 

 

1. There was water in the gas. Ive run through 2 tanks with ISO heet and some of the hesitation i had is now gone. Im not 100% positive all the water is out though as ive never gone below 10 gallons in the tank. (my gauge is wonky)

 

2. The Cam offset is at -4 degrees. I plan to fix this shortly. 

 

3. The catalytic converter is throwing a code for bank one. My guess is that its just gotten old, but it re-codes within a few miles after being cleared. 

 

 

The current plan is to re-time the distributor, gut the cats (for now) and try and run the tank empty or drain it. 

 

 

Is there anything else i should look at while i have the truck down for work? 

 

 

It also idles kind of rough. 

Mikebtte Enthusiast

Mikebtte

Posted
Posted

Plugged cats can cause a lot of low power. I would say that if knocking them out frees up performance, install a new cat and call it good.

All the water in the system would have cleaned out a lot of carbon and could easily have finished off a CAT.

04lss Enthusiast

04lss

Posted
  • Author
Posted
15 hours ago, Mikebtte said:

Plugged cats can cause a lot of low power. I would say that if knocking them out frees up performance, install a new cat and call it good.

All the water in the system would have cleaned out a lot of carbon and could easily have finished off a CAT.

Thanks! 

 

I noticed that the truck seems to have more power when its cold outside by a noticeable ammount. 

Mikebtte Enthusiast

Mikebtte

Posted
Posted

That may be due to the larger amount of fuel supplied during warm up conditions. 

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