Fellow Bricksters,

My wife has a 2001 V70 2.5 (non-turbo), I have an issue that has been going on for quite a while about 6 months and the issue is a metallic "clatter" coming from the motor when it is under load and is very evident at the lower speeds and does not seem to matter if the car is hot or cold. I was putting it down to some poorer quality fuel (I live in Australia and some of the fuel we are forced to buy is rubbish) because once I put in some better octane rating fuel this would disappear. However I have just noticed that it is starting to happen with even the high octane rating fuel.
So just to recap...
A mechanical "clatter" like a tappet noise, however I must be careful in saying this because I am not mechaincally minded at all.. The car feels fine with no seemingly negative effects with this noise

Any help much appreciated.

hey JB, my 01 v70 W/134,000 mi. sounds like it is making the same noise. At first i thought it was the valves, or a bad bearing on the main drive belt adjuster pully. I replaced the pully with no change. I now think that the engine is pinging under any load, the noise seems to be the same hot or cold, and i mixed in 1/2 a tank of 93 octane and didnt notice any improvement. I first noticed this after having the transmisson serviced, at a local trans shop. Is there a knock sensor and if so where, and any way to test. thanks to all for any ideas. BOB D Also there are no lights on or error codes

Hi bobd324,

I agree a complete weird one.. Klaus has given me a couple of things to try (see posts). Keep us informed if you get any further information.

Regards JayBee

There are 2 knock sensors on the side of the block facing the front of the car. The intake manifold needs to be removed to service them. If the knock sensors no longer work, there is an error code associated with that.

Is this noise present all of the time or just when putting a load on the engine?

Klaus
--
I still miss my 164

Try having your mechanic remove carbon deposits from the cylinders. This can be done with water or a solvent like SeaFoam, sucked into the intake manifold (very slowly). The carbon deposits will glow and cause pre ignition, knock.

Is your Lambda light on or any engine errors detected? The knock sensors should be able to retard the timing enough to stop the engine from knocking.

Klaus
--
I still miss my 164

Klaus,

There have been no engine lights come on at all. Would the carbon deposits be causing the issue?? As it does not happen all the time...

Low octane fuel combined with carbon deposits will cause detonation. Your best bet is to find some of that high octane and rev the engine above 5500 a few times, but not in neutral or 1st gear.

Klaus
--
I still miss my 164

ah, the old "Italian tuneup" approach, it may be worth a try. Does the 01 V70 Non turbo have a rev-limiter? I have only had this car 8 months and when i first had it i revved it pretty high but with the high fuel prices i have been driving fairly mellow. other than the noise it runs fine, gets 26 to 28 MPG. BOB D

Bob,

It would have a rev limiter otherwise it would have pistons meeting valves and all other expensive sounding problems. I believe it would mean holding second manually to get to about 50mph, just a guess as I have tried this cure yet... Sure hope it works though
--
1987 740 GL, 1987 740 HP Turbo, 1997 S70 T5 & 2001 V70 all still in the family.....

Klaus,

I still have half a tank of the Premium Unleaded so I will give the 5000 rpm solution a try. It does not happen all the time only under load.. I will give anything a go.........

If this doesn't work, you may be forced to visit a shop that reads Volvo specific codes and see if the knock sensors are working.

Klaus
--
I still miss my 164