XC90 startup problem-warm weather

MixEngineer · Post by **MixEngineer** » 30 Oct 2011, 16:04

Hi all,

I have a 2004 2.5t AWD w/ 86k miles.

It seems when the ambient temp is around or above 70 (F) the engine doesn't startup right away. It will turnover but will either choke on itself and konk out or I'll have to turn the key for a few good seconds. In cooler ambient weather, no problems. The fuel pump was replaced via recall, so that shouldn't be the problem. To try to resolve: I've replaced the sparks with Genuine Volvo and have cleaned the MAF. The problem still exists. I read somewhere that the PCV tube that goes over the top of the engine and is next to the oil cap may be the problem, since they are prone to cracking. Oil level is steady and coolant level is steady, so i don't suspect gaskets or engine seals.

Any thoughts on replacing the PCV tube in order to solve the issue?

MixEngineer · Post by **MixEngineer** » 31 Oct 2011, 09:02

Anyone think it may be something other than the oil crankcase ventilation hose? Not smelling gasoline, so i doubt it has to do with the fuel system, but I'm open to other suggestions from anyone whose had experience with startup problems.

More advanced Volvo DIY'ers: Could this possibly have anything to do with the timing belt or starter? It does turn over, so I doubt starter being the issue.

Thanks in advance!

MixEngineer · Post by **MixEngineer** » 17 Nov 2011, 11:04

Gonna rip out the back seats and take a look at the fuel pump. The more I deal with this challenge, the more it seems like something having to do with the fuel delivery system. I find if I "prime" the fuel before actually initializing the engine to turn over, it seems to greatly minimize the problem. I suspect a leaking pump or something rubber that keeps the pump in place. The pump was replaced under recall, but knowing the honesty of some service centers I wouldn't be surprised if they used a bad pump.

Can anyone get torque specs for the bolts that hold the passenger seats in place? Are there any torque specs for those?

Thanks all!

The Blue Whale · Post by **The Blue Whale** » 20 Nov 2011, 08:22

I had an 2000 xc 70 that had a bad "check valve" that keeps the fuel from running back down the fuel line when motor is off. It had similar symptoms, but temp. had no effect on it.
Could it be an altitude sensor problem?

MixEngineer · Post by **MixEngineer** » 26 Nov 2011, 10:43

Thanks for replying!

I will look into the check valve. That makes sense that a bad check valve could be culprit sense "priming" my engine before actually turning it over helps the situation (or so it seems;)).

Not sure about the altitude sensor... That intrigues me sense I enjoy aviation!

Have a great week!