Fuel Pressure Question 1996 D1

[syugg]

I have a 1996 D1 (without AEL) that's running rough (especially on cold starts) and showing P1171 and P0300 codes. Will be doing a smoke test to check for vacuum leaks within the next few days.

My fuel pressure reading is 36 PSI (motor off). At idle, pressure drops and fluctuates between 29 psi and 31 psi. Are the fuel pressure reading normal? Could this be a sign of a failing fuel pump?

I don't know if it's related or if it was a coincidence but the symptoms seemed to occur after changing the PCV hoses.

Thanks!!!

 

[discostew]

I think its a little low. You might want to take the fuel filter off and see if its restricted.

 

[syugg]

I think its a little low. You might want to take the fuel filter off and see if its restricted.

Fuel filter was recently replaced.

 

[discostew]

Before you replace it back probe the power feed back there with a T pin from the sewing section of Walmart and make sure your getting the full battery voltage across the pump when its running.

 

[Buddy]

What does it read when you unplug the vacuum line from fuel pressure regulator?

 

[syugg]

Just to follow up on this post... I did a smoke test... no vacuum leaks. Replaced the champion spark plugs which was worn. Still idle rough and experience power loss. A code for the lean condition came up. Changed out the fuel pump which was replaced 40,000 miles ago with a new one from Napa Auto (AllMakes Brand). It seemed to do the trick... all seems to idle / run smooth now. Just surprised that a fuel pump would start failing with only 40,000 mi.

 

[HiSPL]

Most fuel pumps that you find at napa or vato-zone are crap nowadays. The airtex brand being particularly craptacular.