2006 XC70 Rough idle, stalls

[2006 Volvo]

Hi,

This started yesterday. I went to accelerate, the engine backfired once then shuddered, ran rough for a bit but then was ok. Got home, parked the car and about 1/2 hour later went back out to the car. It started right away, I drove off and it stalled. No Check Engine light came on. Parked the car for the night.
Next morning, started the car, it revved up to about 1500, dropped down to about 800 then stalled. Checked for error codes - nothing. Did some research. Replaced the plugs, air filter, fuel filter and cleaned the MAF (with MAF cleaner).
Now things are much worse. It is very hard to start, only runs when revved up to 2000+, does not idle at all. Check Engine light is now on. Still no error codes.
Please help.

P.S. Should I have primed/bled the fuel line before trying to start? Do I need to bleed the fuel rail? The fuel filter I put in was longer than the original. Does this make a difference? The filter also did not have an arrow to indicate the direction of flow. I placed it in the same way as the original.

[draser]

Check for gas at the fuel rail, remove cap of the valve and press central pin, wrap a rag around as it will squirt gas. No need to bleed rail, not sure about filter. Are filter ports same size? Can't remember since I replaced mine. Better yet, hook up scanner and read fuel pressure.

[2006 Volvo]

Hi draser;

Thanks for the reply. The fuel filter ports are the same size, no leaks there. I will check the rail for pressure and post back later.

Tried starting this morning. It will fire up with difficulty and only while pumping the throttle, then stalls.

[2006 Volvo]

Update:

Easily started the car this morning. Lots of fuel to the rail. Disconnected the MAF sensor. This made no difference. Took out the plugs and noticed four were black, one still shiny like new. Is this now a coil issue? Engine runs but not smoothly. Check engine light is still on. No error codes.

[vtl]

> Took out the plugs and noticed four were black, one still shiny like new. Is this now a coil issue?

Coil, plug (rarely), injector, wiring from ECU to coil or injector, or ECU itself.

I'd start with replacing the coil. In the morning, without starting the engine, remove coil and plug and look into cylinder - if it's wet, injector is leaking. Put plug/coil back, start the engine, shut it down, look into cylinder again: dry cylinder is either stuck injector or ECU or wiring between them.

For more advanced diagnosis you'll need an oscilloscope.

> Check engine light is still on. No error codes.

Use DiCE/VIDA. Generic OBD-II scanner is of little help with these cars.

[2006 Volvo]

Now my dash message says "Engine System Service Required".

[draser]

Can you do a live scan and post here, preferably idle, 1500 and 3000?

[2006 Volvo]

Took it to the shop today. They said two of my injector connectors were loose. They took care of it and then drove the car. All error codes were wiped and they said all was good. Took the car back and drove about 1/2 block and it stalled. Started easily, then stalled again. Started easily again, kept my foot on the gas for a bit and drove off. After that the engine purred. Parked it. 2 hours later same ordeal: start, stall; start stall; start stall until I was rolling. Then no problem. Got home turned the car off for 5 minutes. Restarted and the same start stall all over again.

The garage also said I should get the cat converter checked as they felt the car had no pep.

[abscate]

If you have an induction hose loose your engine will run like crap as you describe. Follow the air path from the air cleaner and check all hoses for splits, loose clamps, etc.

Are your plugs wet with fuel or oil? See if they dry in sunlight after you pull them.

[Nato Alvarez]

Hello

It would really help to know how this stalling problem resolved.

I have the same problem with my xc70 2004

Thank you