Hi guys,

New member and first time Volvo owner. I hope someone can help me out. I bought an 09 S40 T5 motor 130K. I drove this car for about a month and without warning it just died and won’t restart. Had it tied back home to my garage. I had a couple guys look at it. The timing belt looks like it’s in good shape, it’s tight and no missing cogs. I don’t know what the spec is for fuel pressure, but there is pressure at the test port. I think it may have weak spark because it does seem like it back fires in the exhaust while cranking. So I changed the plugs and coils. But still doesn’t want to start. Any suggestions would be appreciated.

Thanks guys.

 

fuel, spark, compression are all you need :-) plus a computer so I'd start by scanning for stored fault codes. You may need a shop with a full tool like VIDA to monitor run time data. Have you tried spraying some starting fluid into the intake (look for a vaccuum hose etc) - Probably a how to on Youtube. have you done a compression test? turbo engines should be about 150 PSI and you probably need over 100 to start. (if the car jumps timing a notch or two you would see lower pressure ) for spark, are you getting volts to the coils? What do the old plugs look like? For fuel, your car has a pressure sensor and a variable capacity pump. You may see 25-30 PSI after sitting over night, but should bump to 55 when the engine is running. With that said, you can see if you are getting any squirt - ie any voltage pulses hitting the injectors? Does the car sound like it wants to start? You may also want to consider investing in a VIDA CD (usually somebody is selling one or a copy of one on eBay) so you can see the diagnostic procedures... or have a pro with a proper scan tool look at it...

 

It back fires in the exhaust while cranking because the exhaust valves are open when the spark plugs are firing. That means the cam timing is off. It also means it has a good spark, not a weak spark, the plugs are igniting the fuel!

Check your compression first - And diagnose your problem before buying any more parts that you don't need - be sure to put your old coils back in once you cure the cam timing, probably bent valve problems. I'm certain you purchased some aftermarket parts.