2002 V70 rough idle ( slipped timing belt)

Post by **abscate** » 25 Sep 2016, 18:34

No such fail safe

Post by **kcodyjr** » 26 Sep 2016, 18:59

You should ohm out your ECT and see if it's still within spec. The ECU having a wrong idea of the engine temperature plays hell with them.

Usually a car runs better hot than cold. My 1981 was the opposite, because every frickin' seal in the engine was getting old. It's worth shooting a little carb cleaner around the engine compartment to see if it's still sucking air somewhere.

Canadian Moose · Post by **Canadian Moose** » 27 Sep 2016, 19:40

I got a video of the idle issue. It's more of a shudder than the idle problem. As you will see the idle stays solid at around 800 rpm and that's when I get that shudder. As soon as I give it a little gas and bring it up to about 1000 RPM, the shudder goes away.

Post by **abscate** » 28 Sep 2016, 02:27

Check your motor mounts for looseness.

Canadian Moose · Post by **Canadian Moose** » 29 Sep 2016, 19:22

Motor mounts are all good. Today I replaced the coils - no change. Could a low battery, alternator or a short cause these issues? One thing that I noticed is the lights would flicker at the same time as the engine would shudder.

Canadian Moose · Post by **Canadian Moose** » 02 Oct 2016, 17:43

I am getting ready to give up on this issue. I replaced just about every sensor in the car except the o2s. Ripped apart and checked most of the wiring under the hood and at this point getting ready to call it quits. Car still drives fine so at this point this is just an annoyance. If it gets to the point where the car stalls out I am gonna look into it further. I ordered Vida Dice so maybe I can trade the source with that.

Another thing I discovered was a puddle of water under the passenger side back seat. Any idea where that could be coming from?

Canadian Moose · Post by **Canadian Moose** » 03 Oct 2016, 20:58

Would someone happen to have an engine harness wiring diagram? I have what looks like a ground wire with a ring terminal at the end coming off the main harness right near the starter, ETM and evap valve wires. I think it attached to the engine block with a bolt but I am not 100%. It's a 14 or 16 gauge black wire. Anyone know?

Post by **abscate** » 04 Oct 2016, 18:56

You have to scour the Internet for wiring diagrams as we have an agreement with Volvo to not host them here.

They are out there

Canadian Moose · Post by **Canadian Moose** » 06 Oct 2016, 18:22

I think I managed to solve the issue. I pulled the timing belt off and realigned all the marks. After putting it back together the car is idling fine. I think timing might've been off half a tooth at the crank. There is still a shudder inside but at this point I think it is due to the polyurethane motor mount as with the mount removed it is nice and smooth.

Now to figure out where water comes inside the car and accumulates underneath the back seat.

BradGranath · Post by **BradGranath** » 08 Oct 2016, 14:12

Hopefully, just a rotten drain plug?

2002 V70 rough idle ( slipped timing belt)

Re: 2002 V70 rough idle