Rough Idle Got Worse

[MikeF]

2004 V6. Been experiencing a rough idle for a few weeks. Changed air and fuel filters, cleaned MAF and throttle body. Improved somewhat but still idled rough. No problem with acceleration or high speeds. Very peppy. Only problem was at idle. This morning (52 deg)went to start the car and engine was shaking at around 1K RPM and couldn't get it to rev higher. Engine died and restarted doing the same thing. Coils/plugs about 40K miles ago. Any thoughts? Would bad coils/plugs or PCV hose affect idle but, until today, let the car accelerate normally?

 

[joegr]

Yes, particularly the PCV hose.

Did you resolve the brake boost issue? The two problems could have the same cause.

 

[MikeF]

Haven't done more than the tests regarding the booster you suggested. Both tested ok. Went out of town for the holiday last Wednesday and didn't get back untik Monday night.

 

[joegr]

I think you have some vacuum plumbing leaking and/or collapsing.

 

[MikeF]

Thanks for your thoughts on this. That's this weekend's project. Fortunately, I have another car to use.

 

[tireman]

+1 to Joegr

Vacuum leak

 

[Telco]

Yuck. Don't do a visual on vacuum line, give it a bit of a pull. I've seen vacuum line that looked brand new, but when you pulled on it it expanded and looked like black lace. If the line leaves a rubbery black stain and not a grease stain on your fingers it's broken down and leaking. Be careful with it too, because if it's broken down rubber it'll smear all over everything you touch.

 

[jrand]

04v6 might have a recall on the pcv.. i know the 05 v6 was recalled. no time to look it up but someone here might be able to look for you. lincoln replaced mine for free

 

[MikeF]

Found it. The hose connecting the pcv elbow to the tube was disintegrating internally. Thanks for your replies.