Stumble/Hesitation AND stalling: *solved, fuel pump*

[wsteele]

Is it sufficient to use a OBD2 reader to test that or would it be better to rent a gauge from the parts store?

It would depend on the ODB scanner. Not sure most can see the fuel pressure sensor readings.

You might check the Tech 2 sticky in the general discussions section, maybe somebody close has one and can read your fuel pressures, along with a lot more diagnostics.

If you go to most auto parts stores they will rent you a pressure gauge and refund the rental fee if you bring it back. I did this on @Fless’s advice and it worked out great.

Good luck.

 

[bdbull]

Best to rent the gauge and check it at the fuel rail.

Just got the gauge from the parts store. Hopefully will get to it tonight. The OBD2 reader showed it between 42.6 and 43.5, so will be interesting to see how the gauge compares to that.

 

[wsteele]

Just got the gauge from the parts store. Hopefully will get to it tonight. The OBD2 reader showed it between 42.6 and 43.5, so will be interesting to see how the gauge compares to that.

Those look like nominal pressures. If the ODB scanner shows those pressures while driving (good to stand on it a little to stress things), if it is reading 43 psi consistently, your pump and regulator are probably good.

 

[OR VietVet]

Maybe you said it but is it gas or flex fuel?

 

[Doubeleive]

mine runs at 44psi which from what I understand is the minimum considered to be "ok"
that being said mine will run like that very consistently, if your pressure is fluctuating that could indicate a problem

 

[Fless]

Recommend cleaning the throttle body, or has it been cleaned recently? Do these throttle bodies have IACs?

And it might be helpful to restart this in its own thread.

 

[bdbull]

Started a new thread: https://www.tahoeyukonforum.com/threads/stumble-hesitation-and-stalling-continuation-thread.130009/