major idling problem... please help :(

**SchweetMunkie** · 10-13-2008 10:29 AM

Hey all. I hope I can get a few ideas.

Here's the lowdown... I have an '04 A4 1.8T. I had a couple of the recirc hard hoses fall apart a few weeks ago. I replaced the factory elbow coming up from the oil cooler, and replaced the uber expensive zig zaging hardline with 5/8 hose, which seems to work just fine. I then replaced the puck thinking that it was causing rough idle. Still nothing. I've been up to the dealership (I know a tech) who read my codes with their expensive gizmos. I have P0300~304 (most likely because when it runs rough at idle) and P1297, which I can't remember the exact verbage of the code. Their troubleshooting tree is kinda useless for this code. It told us to do a check on the maf, an alignment on the TB. After checking the electronics, there doesn't seem to be any major parts glaring at us. It does say something about a mechanical recirculation valve, is that the DV? Anyways, I'm at a loss...my car doesn't run well, and I really don't want to throw money at parts hoping to fix it. I'm about to do the N249 bypass to see if that is causing any problems, but I'm kinda doubting it. I had a code for lean bank 1, which also seems to be a byproduct from it idling poorly. However, the Audi computer says that it's running 9% and 7% rich (WOT and idle, but i can't remember which is which). Can anyone help me out with ideas? I've only had this car for a few months and I'm ready to drive it off a cliff, if it would drive me there.....

Thanks in advance for any help or suggestions.

**BNZ TOY** · 10-13-2008 10:34 AM

"mechanical recirculation valve, is that the DV? " That sounds like the DV to me. However, i'm not sure how it would be affecting your idle too much unless it's stuck open. Is it stock?

**Molotov** · 10-13-2008 10:36 AM

skimmed your paragraph quickly.. try unplugging the MAF yet?

**SchweetMunkie** · 10-13-2008 10:44 AM

Stock DV and yes, we unplugged the maf while it was idling and it didn't seem to make a difference. is there a way to test the dv?

**BNZ TOY** · 10-13-2008 11:12 AM

Not sure how deep you are planning into modding your ride but that stock plastic pos bov should be replaced anyways.

**SchweetMunkie** · 10-13-2008 11:22 AM

Right now, everything is stock. Would the DV cause idle problems? I'm making boost at speed...

**BNZ TOY** · 10-13-2008 11:25 AM

When, you did a search on "Idling", which diagnosis sounded the closest?

**SchweetMunkie** · 10-13-2008 11:50 AM

I've tried a bunch of things. If the car was running poorly at idle, and I unplug the MAF, would it get better or worse? When I tried this, there was no change, would this point to the MAF?

**SchweetMunkie** · 10-14-2008 04:45 AM

No other suggestions? Believe me, I've been searching this and other sites for a few days before I started posting. I didn't want to miss something easy.

**zcrew** · 10-21-2008 07:01 PM

i'm going through a similar problem at the moment, except i haven't had it read by a nice scanner yet, just a cheapo autozone that said i'm running rich. i know one of my check valves its pretty busted looking, so i'll probably replace it, and maybe that will help. i'll keep you posted if i remember