When i nls from 3rd to 4th it bogs i can feel it, last week at the track i got the p0089 which the fuel pressure regulator performance. I cleared it and it didnt come back until i nls from 3rd to 4th. its just between 3rd and 4th. Any clue why?

Mind you i have been driving and it hasnt come back, Whenever i nls i from 3rd to 4th i feel the bog down

I ran 13.3 @ 108 on winter tires, BTW....

Byt Tuned @ 22.7 psi...

 

P0089
• The fuel pressure adjustment is greater than +2.5 MPa (+363 psi) or less than -2.5 MPa (-363 psi).

• The DTCs set when the above conditions are met for 4 seconds.


Could either be the fuel rail pressure sensor is faulty or even got oil leaked on it from the pesky leaks our LNF's get...

OR, it could be the HPFP going out.

If it's the latter, this will be the 3rd Cobalt within a week I've seen the HPFP go out which includes mine

 

Thanks for the reply, it hasn't happened with dd.... so I don't think its going bad...it is however sweating over by the cam acutautor...

 

I replace the sensor first, since its the easiest I don't know if I wanna roll into the dealership with my tune and tell to fix the pump

 

My pump didn't act up until WOT in 3rd or 4th gear doing a pull. It'll work fine until about 3800rpm and then cuts out for 1000 rpm and then shoots back up after 4800 rpm.

I was logging pressure in HP Tuners.