I have a 2000 S40 with 115K miles on it. Lately, it has been getting harder to start the car. I just changed the fuel filter about a week ago and that didn't seem to fix a thing. Also as a point of interest, I changed the coils and spark plugs about 25k miles ago.
For the past couple of weeks the cooling fans come on as soon as the engine starts and seem to continue to run for 7-8 minutes after the engine is turned off even though the engine is not running hot at all. In addition, the engine is also becoming difficult to start.
Case in point... Last night my family went to eat at a nearby restaurant, only a couple of miles from the house. I don't think the engine even got up to full operating temp before we were parked and went in to eat. Came out about 45 minutes later and could not start the car. The car turns over freely but it just won't catch. I crank it for several seconds and the car will fire and make a feeble attempt to run, and it just dies. Tried repeatedly for about 15-20 minutes before I called a friend to pick us up and take us home. Returned about an hour later and was able to get the thing started. The one saving grace is once it's running, it runs terrific. On the highway, it seems to have plenty of power and accelerates nicely from a stop.
I'm not a pro, but it seems like there is an internal choke that is or is not engaging properly and it seems to very neatly coincide with the cooling fans wanting to run all the time. Any suggestions are warmly welcomed.

 

You might have a temp sensor that due to being bad or having a poor connection is sending the wrong temp to the ECU. For instance if the ECU thinks your engine is hot - it will be difficult to start when the engine is actually cold.

A compatible scan tool that can show live data will be able to verify if your temp sensor is working correctly or not.

There are certainly other things that can cause hard starting - so don't just replace a part until you can prove it's a problem!

 

could be due to a faulty engine coolant temperature (ECT) sensor or a malfunctioning thermostat. These components can cause the cooling fans to run constantly and may also affect the starting of the engine.

 

Hoonk, thank you my friend, for your quick reply. I was hoping it may be a rather simple fix. It appears that this is a logical item to try.
Thank you again.

 

Steve, thank you my friend, for your quick reply. I was hoping it may be a rather simple fix. It appears that this is a logical item to try.
Thank you again.

 

on the gen 1 s40s, long cold cranking can be caused by a leaking fuel pressure regulator which allows the fuel rail pressure to bleed down. The quick test is to find the FPR on the right side (ie near #4) of the fuel rail - you'll see a small s shaped vacuum line. If you pull that line after the car has recently been running and fuel leaks out, it means you have a torn diaphram that's allowing the residual pressure to bleed off. 15 minute repair, $200 part ugh.

 

Hey mt6127,
Thank you for your insight. Your description was spot on. Looks like I'll be replacing this little gem as well.
Thank you for your post.

 

You might have a temp sensor that due to being bad or having a poor connection is sending the wrong temp to the ECU. For instance if the ECU thinks your engine is hot - it will be difficult to start when the engine is actually cold.