No power on acceleration

Bajakid1450

Well-Known Member
So in 1st and 2nd gear there is no power but 3rd gear around 2500 rpm the power kicks in, so if I floor it in 1st or second from a stop or while rolling it has really no acceleration
I’m thinking fuel related since all the sensors, coils, and plugs are new. No surging idle and not dying out thankfully just a slingshot of power that’s not there in first or second
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Gtstorey

Goblin Guru
Do you have higher rated map sensors for the supercharger running with the stock tune/ecu?

I can't think of a lot of things that would be dependent on gear selection vs engine rpm other than some torque demand restrictions.

Any check engine light/ DTC's?
 

Gtstorey

Goblin Guru
So I think the P0300 code is random misfire code. I would think you will need to track that down and correct it. That one can be hard to track down and you will have to go through firing, fuel, vacuum and mechanical to eliminate it.
 

Bajakid1450

Well-Known Member
So I think the P0300 code is random misfire code. I would think you will need to track that down and correct it. That one can be hard to track down and you will have to go through firing, fuel, vacuum and mechanical to eliminate it.
fun...... :( well I know what I’ll be doing this weekend
 

Bajakid1450

Well-Known Member
So I think it has something to do with a crank position sensor relearn. I tried it with 3 different ecus and none of them will let me do a CKP relearn
 

Bajakid1450

Well-Known Member
If my friend has a hptuner will that work, because the Snapon scanner and diagnostic tool won’t allow that function to work on the cobalt but on a Silverado or suburban it works fine. I’ve got good compression on all cylinders and all are firing, all sensors are new, and runs smooth other than after 5 minutes of driving after clearing the code for p0300 I can get on it and have fun then next redlight the cel flashes and it bogs down and drives like a old granny. Weird right...?
 

Bajakid1450

Well-Known Member
This article says to start with a vacuum leak test. Have you already done a smoke test?
If no vacuum leak is found, test the ignition and fuel system components next.... then a compression check.
smoke test good, ignition good, compression good, and injectors and fuel filters new still gotta check fuel pump pressure. But everything is fine till I get on it then if I clear the code it’s fine again till I get on it again
 

Ross

Goblin Guru
I was able to test fuel pressure using my A/C gauge set. Your local auto parts store may have a free rental tool for this too.
 
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