06 XC70 Engine Cuts Out

TahoeXC · Post by **TahoeXC** » 02 Mar 2021, 21:24

Need some advice: My 06 XC70 is miss behaving.... The car started cutting out on the freeway without CEL. VIDA led me to believe it was FPS and PEM. I have replaced both, along with fuel pump. Was running fine and all of a sudden cutting out is worse. Now it does not self correct, I have to pull over to the side of the road and restart car. No issues at or after restart until it fails again which can be anywhere from 1 to 5 minutes after resuming travel.

VIDA is throwing a ECM-2900 Fuel Pressure - Faulty Signal and ECM-290D Fuel pressure - Signal too low.

Watching the graph in VIDA when the car is running fine Fuel Pressure is @ 382-ish kPa and duty cycle is 40%-ish.

Then when it cuts out there is an immediate spike in the duty cycle to a plateau and a corresponding drop in fuel pressure.

So the question: Is this an electrical gremlin in say the CEM or is this dirt/gunk in the fuel tank?

Really like some insight before I tear into the tank again...

Post by **abscate** » 03 Mar 2021, 03:22

It’s very easy to kink the fuel lines doing a fuel pump on aP2 XC. Only diagnosis is to remove and inspect.

TahoeXC · Post by **TahoeXC** » 03 Mar 2021, 06:52

OK, not ruling out kink upon install, but if that is the issue why would the car have had similar symptoms pre fuel pump replacement? And if it is a kink what is the significance of pulling over, turning the car off/on and being able to immediately drive away? Wouldn't a kink restrict fuel flow all the time and show a much higher duty cycle and not pass Vida fuel pump test?

Post by **xHeart** » 03 Mar 2021, 07:25

TahoeXC wrote: ↑02 Mar 2021, 21:24 Need some advice: My 06 XC70 is miss behaving.... The car started cutting out on the freeway without CEL. VIDA led me to believe it was FPS and PEM. I have replaced both, along with fuel pump. Was running fine and all of a sudden cutting out is worse. Now it does not self correct, I have to pull over to the side of the road and restart car. No issues at or after restart until it fails again which can be anywhere from 1 to 5 minutes after resuming travel.

VIDA is throwing a ECM-2900 Fuel Pressure - Faulty Signal and ECM-290D Fuel pressure - Signal too low.

Watching the graph in VIDA when the car is running fine Fuel Pressure is @ 382-ish kPa and duty cycle is 40%-ish.

Then when it cuts out there is an immediate spike in the duty cycle to a plateau and a corresponding drop in fuel pressure.

So the question: Is this an electrical gremlin in say the CEM or is this dirt/gunk in the fuel tank?

Really like some insight before I tear into the tank again...

I had similar issue last summer. The engine was cutting out at deceleration. It will start and run fine as long as I had the gas pedal depressed -- taking the foot off the pedal will cause it to hesitate, struggled to idle, and cut off, but not always.

In my case it was failing air intake system, more here viewtopic.php?f=9&t=95124

It feels like you've air/fuel issue.

Post by **abscate** » 03 Mar 2021, 07:47

TahoeXC wrote: ↑03 Mar 2021, 06:52 OK, not ruling out kink upon install, but if that is the issue why would the car have had similar symptoms pre fuel pump replacement? And if it is a kink what is the significance of pulling over, turning the car off/on and being able to immediately drive away? Wouldn't a kink restrict fuel flow all the time and show a much higher duty cycle and not pass Vida fuel pump test?

If it did pre- fuel pump replacement, Ill stipulate that a kink probably isnt the root issue.

User shockwave went through XC90 Hades in that forum with that two years ago, and wrote up how annoying the kink is - it doenst show up on pressure or VIDA tests, unfortunately.

Jimmy has written about how you can get blockage from the fuel sock that is maddening to diagnose.

Post by **oragex** » 03 Mar 2021, 12:22

Could it be a bad PEM ? It's $50 used off Ebay. Or bad FPS