Good morning

I have a 2001 s40 that has all of a sudden began to run rough, stall and have very poor power on acceleration. I know there are numerous threads already with layers of fixes but on mine i seem, and i may be hearing things, a vacuum noise, it seems when it runs rough i am hearing something opening/closing as i sit at the steering wheel it goes on for like 4 seconds twice and stops??? could there be something like that happening and contributing to my problem?? thank you!

 

Throttle body problem and or MAF ???
Disconnect the MAF and see if if anything changes.
Check out all your vacuum lines also for any loose or split.
Have your fault codes read. That may give you the lead you need.

 

will check, when I first had it scanned my mechanic said there were 10 codes, pointing to everything. we cleared it and then when the cel came on i took it to autozone and it had a p0107..but from reading posts on this seems like you have to shotgun everything, codes dont point to anything specific. But with the noise of something opening/closing it seems weird. I read these were some of the most reliable cars, they are i guess until you have issues that point to very many things..thank you for advise

 

That code is possibly related to your MAP sensor being faulty.
see link below for symptoms.

Unplug it and see if she runs any differently. That helps narrow it down but yes, many things can all contribute overall.

Bad Map Sensor? - Ask.com

 

Thank you. appreciate it. i will check that.

 

Good morning diff,
I am awaiting a map sensor, but someone on amazon had a post that they had to clear the codes for the new sensor to work??? are you aware of anything. i do not have a code reader, i can buy, but i was wondering if you have ever heard of that?

thank you very much

 

Many auto part suppliers have code readers that they allow customers to use for diagnosis of problems.
Wise to clear all the existing stored codes to rule out each issue.
If they keep reappearing then its likely that your problems have not been resolved and you may have other causing factors.

 

The noise is probably the electric vacuum pump.

The running problem could be your fuel pressure regulator.

 

vacuum pump?? that sounds like it. it "appears" it was my map sensor. changed wires, and booster sensor, problem was better but still a rough idle, did map sensor cleared codes and 50 miles so far and still so good..thank you for input. i apprecaite it