So, I'm on my eternal quest at Volvo S40 Sensor Whack-a-Mole!! I'm actually getting pretty good at this and I REALLY appreciate this Forum for clues and pictures and general advice... I'm much braver WITH you all than without you!

So, the latest is an odd Stalling Under Power issue that has started. Throwing a P0102 (Low MAF) and a P0103 (HI MAF, go figure). I replaced the MAF Sensor 2 years ago, so I'm kinda doubtful that it's the MAF, but maybe connections.

And, the car always runs great for me, but of course stalls on my wife in random times, and then starts right back up no problem. I've noticed that it tends to throw the codes and act "funny" after I've gotten gas. Been using regular CA gas forever.

Today, after I got gas (another clue) it threw codes when I started it back up. P0102 AND now a new one P0326 (Knock Sensor #1 / Bank #1). So, I've searched the forums but not really a lot of hits for the P0326 and S40's...

I'm going to replace the Fuel Filter this weekend, cuz it's probably old and I replaced the Fuel Pressure Regulator a couple weeks ago cuz it had been getting harder to start when cold... That cleared that issue RIGHT UP, BTW...

So, any ideas? I'll check the MAF connections this weekend... I did replace the Gas cap also, recently, cuz it seems to throw the codes and do the stalling thing after I've gotten gas...

Any help is appreciated. Thanks!! - Geno

 

Sorry for your troubles. It's weird that it happens often after gas. Fuel filter is an easy job and low hanging fruit to resolve this if that is what it ends up being.

What octane on the gas?

I had some p0102's back in March. I cleaned the MAF, cleaned the connectors to it and it cleared for a bit but I ended up getting a new MAF and making sure I didn't put as much oil on my K&N filter.

As a general check, there is a hose off the intercooler to the idle air control valve (right under the throttle body cover), check it for leaks. It is easily missed for being rock hard and having a crack.