What do you think - is it the fuel pump, PEM or FPS?

bfry · Post by **bfry** » 23 Oct 2021, 10:44

2006 XC90 2.5T AWD

After driving on the highway >= 60 mph for at least 30 mins, the car consistently all of sudden bogs down and smells of gas. It then stalls. If I let it sit for 5-10 mins, it’s ok and the process repeats. I have zero trouble driving around town or traveling at highway speeds for a short amount of time.

FPS was bad maybe 2 yrs ago? and was replaced. Fuel filter was replaced <1 yr ago. I re-did the breather box 1 yr ago - I bring this up only because the rail was removed - maybe I didn’t replace it correctly but then why would it take a year to start acting up? so in my mind a low chance that i messed up the rail re-installation.

I get the following codes…

ECM-212C Long-term fuel trim, bank 1 - Signal too high

ECM-21EC Long-term fuel trim, bank 1 - Signal too high

ECM-2900 Fuel pressure - faulty signal

ECM-290D Fuel pressure - signal too low

I also have the following code that started towards the end of the summer which I’m curious about - the a/c doesn’t blow cold anymore…ECM-520D A/C pressure sensor - Signal too low

I appreciate any guidance - thank you!

Post by **kallekula** » 23 Oct 2021, 10:57

Check fuel pressure. Tape it to your windshield so that u easily can check current pressure when things go bad.

Post by **ggleavitt** » 24 Oct 2021, 20:27

Might be a bad PEM.

Post by **cn90** » 25 Oct 2021, 16:20

1+,

The way to diagnose bad PEM is to find a good used PEM from either junk yard or ebay.
Ask the ebay seller to see how many miles on the PEM, usually there is a date stamp on it (date of mfg).

Then swap it, if problem goes away, then it is the PEM.
Search forum for locations.
In my 2005 XC90 2.5T, it is in front of the RR tire.
Make sure you use jack stand and place it at the correct locations for sfatey...

Post by **abscate** » 27 Oct 2021, 04:01

Where are you in NY, bfry?

I’ve got a couple of PEM spares for diagnostics.

bfry · Post by **bfry** » 24 Nov 2021, 11:09

Sorry for the delayed response - I have not worked on it since my last post.

I’m in lower Westchester County.

Gonna try and test fuel pump today or in the next few days.

Thank you.

Post by **abscate** » 26 Nov 2021, 02:27

If you had fuel pump work done it is really easy to kink the furl crossover line in the tank during that. See the thread here by user “ shockwave”

bfry · Post by **bfry** » 29 Nov 2021, 15:40

So I figured out the fuel pump only has about 50k on it so thinking it’s the PEM. Problem is it’s not under the liner of the rear passenger wheel well liner and not next to the fuel filter underneath.

Maybe under the middle seat row? Also have seen the rear quarter mentioned as a possible location.

Anyway to know for sure before I needlessly remove something I don’t have to?

Chassis # is 32AB65426952.

Thank you.

bfry · Post by **bfry** » 30 Nov 2021, 08:09

Called dealer this morning - gave them VIN.

Said it’s on top of tank - not accessible through floor by removing seats.

Can anyone else confirm? I kinda feel like they’re maybe making it sound like it’s more difficult to access so I bring it in?

Thx

2006 XC90 2.5T AWD

bfry · Post by **bfry** » 30 Nov 2021, 09:20

Ok - got it up on ramps and as far as I can tell the tank is flush against the underside. I looked closely and no sign of the PEM so gonna remove back seats.

I did examine both sides of the rear quarter pretty closely as well and no signs there either.

BTW, if anyone is wondering, I did not do the fuel pump replacement myself previously…