Hey gang, I'm getting a 4-3-3 from my check engine light, which tells me I have a bad Rear Knock Sensor. I looked in my Haynes manual to see what I was in for to replace it - but it didn't tell me much. Has anyone out there replaced one before? What skill level would you rate it (1=easy & 5=hard)? I found the part pretty cheap online....but want to make sure this isn't an impossible repair for a weekend wrench turner like myself.
Thanks in advance to anyone with thoughts and pointers.

QuickBrick (James)
94 855T
93 245 (M47) FOR SALE
91 780T

I had the same code and replacing distributor cap, rotor and wires fixed it. Volvo tech told me it was probably distributor cap but I didn't want to waste my time chasing the fault so replaced the three components.

Very interesting, I had those tune ups planned for the weekend as well, maybe I'll do the cap, rotor, plugs and wires first and see if I can avoid tearing into any further if I don't have to....

Thanks for the heads up - could save me a lot of time and frustration.

James

Jen,

Wow - that was it. I replaced the cap, rotor, plugs and wires (nice 8.5MM Magnecors) and resest the DTC Code and voila - the check engine light went off and stayed off. Now I can return the knock sensor kit, intake mainfold gaskets, etc. and sleep better.

Thanks for leeting me know - I would have just jumped in there and done the tunes up and knock sensors all at once - you saved me a ton of time and some money.

Did I mention "thanks!"????

James

I'm glad that it worked.
Ignition is one of few problems that may produce a trouble code leading to totally unnecessary repairs. Secondary air injection is another one that is misreported and misdiagnosed, vacuum lines problems may lead to both oxygen sensors replacement.
Maybe it's time to compile a list of cheap fixes to what appears as an expensive problem.

Good idea Jen. Any pointers on the ABS/TRACS light coming on occassionally. I suspect I just need to clean my wheel sensors.

Sorry, can't help you on that, luckly I haven't had too many problems with my V70. Try volvospeed.com as Rich may have a tip or two.

Its not too difficult. You will have to remove the intake manifold to do it however.Also i would use new parts as Volvo has upgrade the sensors.

Thanks - I'll give it a shot. Besides the intake manifold gasket, should I plan to replace anything else while I am in there? Fuel Injectors seals? Anything?

I don't think there is an intake gasket. I remember reading somewhere that it uses a sealer similar to silicone. Not sure about that... Worth checking however.