Strange noise and reluctance to start!

[BlackC70]

Hi all, first post :)

Right, I've got a C70 coupé but it's just the 2.0 LPT version, however I don't think any of my problems are related to the engine (other than the fact it's not the quickest thing on the road by a big margin!)

Firstly - when you're driving at around 50+mph, sometimes you get to hear a hollow knock type noise coming from the roof, putting the sunroof up dulls the noise a bit but it's still there, it usually happens when the road undulates - I thought it might have been the control cables for the sunroof but I'm not sure. It's hard to explain the noise, it's as if someone is kicking the tyres as you drive! Any ideas on that?

Secondly - do the 70 series cars have a problem with the immobiliser pickup aerial? Sometimes you go to start the car and it either just turns over and over, or it will catch and then cut out, pressing the throttle doesn't have any bearing on keeping the engine going. I talked to a bloke at Volvo and he said it sounds like it could be the immobiliser aerial that surrounds the ignition barrel, but couldn't tell me if it would bring a code up if it was plugged into the computer. I tried an OBD2 reader and it didn't read anything off, but I'm not sure it could read security system fault codes (just engine codes).

Thanks in advance :)

[Rufe]

first of all, let me welcome you along :)

now i have never heard of this noise you mention in the roof, but the immobilisers can suffer with a bad antenna ring, and this is the most likely reason for your problem from what you say above. from what i know, there is not a fault code for this problem.

[BlackC70]

Thanks for the welcome :)

I wish I could be more specific about the noise but it only happens occasionally, from the drivers seat it sounds like it's from directly above and slightly behind you, and from the passenger seat it sounds like it's directly behind the driver... very strange!

As for the immobiliser antenna, is it an easy fix (relocating it a bit) or does it require replacement? If it needs replacing is it coded to the car and as such require main dealer recoding or just a plug out plug in job?

[thunderace]

hello and :welcome:

[BlackC70]

so is it an easy fix to swap the immobiliser antenna over? or does it require recoding at the dealers?

[T5chris]

Hello bud,

Sorry for not replying earlier but have been away.

I had the same non starting problem with my C70 T5 ie. would start fine then every now and again it would just spin the starter with no spark.

As you suggest the problem with mine was a faulty antena ring which took about ten mins to change. (steering cowling off then unclip harness and ring slides off ignition barrel). Ring cost me just short of 20 quid from Volvo.

Hopes this helps
Chris....

[BlackC70]

That helps a lot mate :) For 20 quid it's worth trying!

Cheers!

[Paul]

Good luck hope all is fine awsome car to drive!

And welcome