2002 S60 Clicking Noise From TCV?

Post by **velorider** » 23 Mar 2015, 15:39

About a year ago I replaced the PCV breather box. Upon 1st startup I noticed a loud clicking noise from the engine compartment. Originally I thought it was the TCV value, IPDUSA HD TVC, but after a quick evaluation everything worked find and I was tired so I left it.

Jump ahead a year, after replacing the MAF sensor I got curious again about the clicking. After some MVS searches and google searches I think it might now be the EVAP purge valve. Hence prior note about PCV breather box replacement.

I haven't figured out the pattern of when it clicks or doesn't, it does not aways click, but often enough. When I get home tonight I will use the old school garden hose stethoscope and see if I can pin point it to the EVAP.

So it is normal to hear rapid clicking from the EVAP valve?

If not is it as simple as replacing the EVAP valve, or might the actual root cause be more complicate, like the ECM.

Thanks
John

Post by **velorider** » 23 Mar 2015, 20:26

So I checked tonight and it is definitely the TCV. While running and clicking away I plugged the TCV and the clicking stopped.

I checked the differential voltage between the two pins and it was 14.4 and 3.5. So it definitely the TCV. I read a long post on sweedishspeed.net that wasn't very conclusive.

Hopefully someone on MVS has some insight into why the TCV would be clicking at ideal.

Post by **vtl** » 23 Mar 2015, 21:33

TCV is pulse-width modulated, you need oscilloscope to look at signal and response. My IPD HD TCV died (solenoid was not properly responding to low duty cycle) in about a year. Put old OE TCV back.

Post by **velorider** » 23 Mar 2015, 23:57

Interesting about the IPD HD TCV, thats whats in there now. The stock stopped working so I replaced with IPD HD TCV about 5 years ago.

I agree about the oscilloscope to measure PWM, but my understanding is the TCV should be "off" at idle. So voltage differential should be 0 and not opening and closing.

I ordered a new TCV and I'll report back if its just a bad TCV. I'm hoping its just the TCV otherwise I fear this might be a complicated issue. Currently no MIL.

Post by **xHeart** » 24 Mar 2015, 08:44

TCV is also known as Boost Control Solenoid (BCS).

Our 2001 V70XC sputters for some 30Sec with the start of engine, then stops. If I turn off the engine immediately, the sputter is loud due to its proximity to the air-box.

Does it need replacing?

Volvo PN 9473212. Pierburg is OEM for $40.

Post by **velorider** » 28 Mar 2015, 21:32

In the end, replacing the TCV resolved the issues.