1998 V70 rough idle after PCV replacement

brunocerous · Post by **brunocerous** » 26 Dec 2015, 11:16

Hi all, and happy holidays!

I decided to tackle my PCV during some free holiday time I had, and I'd love some help figuring out what went wrong.

I'll admit up front that I started doing the work before I had disconnected the battery, only realizing it at some point when I was pulling off the fuel rail. At that point, I stopped and disconnected it, then continued.

After everything was back together, I started it up and got a wildly varying idle rate, from about 600-1,200rpm, back and forth, which you can see in the first video. When my brother arrived, he filmed the second video, in which you can see a spark (arc?) at one of the fuel injectors. After shutting the car off, a faint electrical buzzing sound could be heard in the vicinity of the PCV flame trap.

Is it possible/likely that I shorted part of the system? If that's the case, what's my next step?

Previously, I had a P0455 code, which I had hoped the PCV system replacement would address. Now, I get no codes, but the car doesn't run.

Any help would be greatly appreciated.

Post by **RussB** » 26 Dec 2015, 12:27

Did it run OK before you replaced the PCV system?

humbertoflores63 · Post by **humbertoflores63** » 26 Dec 2015, 12:31

You need to unplug the battery first and recheck all the electrical connections from the items that you unplug to do the PCV service.

Make sure to fit the connectors properly, and also check the vacuum hoses for a proper fit.

brunocerous · Post by **brunocerous** » 26 Dec 2015, 12:37

It was running beautifully, although the PCV hoses were hardened and it failed the "glove" test.

brunocerous · Post by **brunocerous** » 26 Dec 2015, 12:38

That sounds like as good a place to start as any. I'm going to redo it now. Hope to have a positive update soon.

humbertoflores63 wrote:You need to unplug the battery first and recheck all the electrical connections from the items that you unplug to do the PCV service.

Make sure to fit the connectors properly, and also check the vacuum hoses for a proper fit.

Post by **misha** » 26 Dec 2015, 13:30

Go back and re-check every connector and vacuum line you needed to disconect.You messed something up during the process of replacement.
Usually,people don't install manifold gasket properly and car runs like crap.

Post by **cn90** » 26 Dec 2015, 13:37

Been there done that.
Usually the hose to the ICV is disconnected, causing unmetered air to enter the system.
Check every single connection, clamps etc.
Also, the I.M. needs to be torqued properly.

Post by **erikv11** » 26 Dec 2015, 18:06

By far the most common of rough idle after PCV is the little bracket is lodged under the bottom right corner of the intake manifold, leaving a vacuum leak.

Post by **abscate** » 27 Dec 2015, 06:21

Fear not, after you find the leak or hose, your chariot will run beautifully once more.

Ditto on the advice to inspect the manifold and IAC. If you can see sparks, track them down and stop that quickly before it damages something.

brunocerous · Post by **brunocerous** » 27 Dec 2015, 10:39

abscate wrote:Fear not, after you find the leak or hose, your chariot will run beautifully once more.

Ditto on the advice to inspect the manifold and IAC. If you can see sparks, track them down and stop that quickly before it damages something.

Thanks so much for the words of encouragement. It really does help to hear a voice of support.

I see that the manifold bolts are supposed to be torqued to 18 ft/lbs., which I did.

Could the spark at the injector be caused by a vacuum leak?

I rechecked everything, every hose and bolt, and the car is stalling. When I cranked it, I could hear a clicking sound in the vicinity of the fuel rail, followed by a slight gasoline smell and a faint electrical-type buzz afterward. I don't have help right now to pinpoint the clicking sound.