First start of the day, cranking takes 3-5 seconds

[Jekuh123]

Hello all,

 

I'm new to this forum. I already tried searching for this issue, but I couldn't really find a match. Could be because I am just not good at searching, so if that's the case, don't be afraid to shoot me.

 

I recently bought a 4th gen Subaru Legacy 2.0R. The day after I picked it up, in the morning, it took quite some time to get the engine to start. At first I thought that this might be the battery, as the car had been at the dealership for over a year. But after 2 weeks of driving back and forth to work (approximately 1000km), with stretches of 200km at once, I still have the same issue. Every first start of the day, I need to crank for some 3-5 seconds. All other starts during that same day are pretty much instant.

 

I just went to a local parts store, where they measured my battery. The results read: 12.87V and 446A (whereas the battery is only rated at 390A?). So according to these results, the battery is still good, and apparently even better than advertised. The guy from the store suspected that maybe the sparkplugs are dirty or that the fuel flows back into the tank overnight. He suggested to put the contact to ''on'' for a few seconds, then back off again. Then on again, wait a little while and then start. That way the fuel pump would have some time to get fuel upstream. I haven't tested this yet, as I only just got back from the shop, but I already wanted to ask this here, to see what else this could possibly cause, or if he's right, what I can do about this.

 

As a side note; the temperature here (Belgium) has been between 2 and 16 degrees Celsius these 2 weeks, so not really cold I'd say.

 

 

Many thanks in advance.

 

If you need any more information, I'll be happy to provide that!

[bluesuby]

How old are the plugs? And if you bought it at a dealer, they should find and fix the problem. I don't know what rules protect consumers in Belgium, but I think it would be fair to have them resolve the issue.

[socalsleeper]

You might have fuel pressure bleeding back overnight. There is a valve on modern cars to keep some fuel pressure in the lines for cold starts.

You should be able to get a fuel pressure gauge on one of the lines in the engine bay to see the pressure bleed down.

[SubOperator]

You might have fuel pressure bleeding back overnight. There is a valve on modern cars to keep some fuel pressure in the lines for cold starts.

You should be able to get a fuel pressure gauge on one of the lines in the engine bay to see the pressure bleed down.

 

^^^ This. I have the same exact issue on my 05 LGT and wife's 07 Tribeca. Pressure drops overnight just a little.

 

If this really bothers you then you may need to replace injector seals and/or seals in the gas pump in the gas tank. I did both for my son's 05 Outback rebuild and it starts instantly always.

 

Or you may let the key stay in ignition for same 3-5 seconds and let the pump bring the pressure up before cranking. This resolves the issue of first cold start in the morning and that is what I do.

Edited April 30, 2021 by SubOperator
Double spacing again?

[Max Capacity]

FWIW, I always turn the key to "On" put on my seatbelt, then start the car, or at least let the gauges sweep before I start it.

[Jekuh123]

Thank you for all the quick and extensive replies!

 

@Bluesuby; No idea how old they are. Regarding the warranty, I can always go back and see what they can/want to do for me. It's good to know now what probably causes it, so I can already tell them.

 

@Socalsleeper and @SubOperator; Good to know that this could well be the issue! To replace those seals you mentioned, is that an ''easy'' fix, or do I need to remove a lot of other components to reach them? For the record, besides it being a bit of an inconvenience, this problem does not harm the engine in any way, also on the long run?

 

@Max Capacity; I've been doing that ever since I got it! I guess I will take a little more time to put on my seatbelt as from now on

[socalsleeper]

Thank you for all the quick and extensive replies!

 

@Bluesuby; No idea how old they are. Regarding the warranty, I can always go back and see what they can/want to do for me. It's good to know now what probably causes it, so I can already tell them.

 

@Socalsleeper and @SubOperator; Good to know that this could well be the issue! To replace those seals you mentioned, is that an ''easy'' fix, or do I need to remove a lot of other components to reach them? For the record, besides it being a bit of an inconvenience, this problem does not harm the engine in any way, also on the long run?

 

@Max Capacity; I've been doing that ever since I got it! I guess I will take a little more time to put on my seatbelt as from now on

 

The injector seals are not hard, but are a pain in the butt to access due to some of the brackets in the area. I don't think that is your problem though. Bad injector seals will leak fuel on the engine, and fuel stinks and attracts a lot of dirt and grime so you would likely notice the stuff on the engine.

Now take this next part with a grain of salt. I am not sure were the anti-drain back valve is on this car, it might be in the engine compartment, or part of the fuel sending unit. I know the germans liked to have this in the rear so the whole line held pressure. I remember reading specs for different cars, something like (3-5 psi drop per hour was normal) I pulled these numbers out of my ear but you get the point.

Just as a point of reference base fuel pressure for these cars is around 40-ish psi and will increase with boost. That is what the mess of hoses and valve are for on the drivers side of the engine bay.

 

While we are on the subject is is also possible to have a leaky injector, but if that was the case you would have a terrible smell of raw fuel when you started the car. Take a sniff of the oil if it smells like gas you might have a bad injector, unlikely, but not impossible.

[Jekuh123]

Thanks for the reply socalsleeper!

 

I tried the turning on of the ignition key, and then leaving it for some time (tried 5,10,20 seconds). Unfortunately, none of these starts were any different compared to not waiting at all. Regarding the bad injector, I doubt that too tbh, because I do not have any fuel smell and the engine bay is actually really clean. Also, whenever the car starts within a few hours of the "first" start, it's pretty much instant. I do believe that it is the pressure in the lines dropping, as the start becomes longer, the longer the car was off. Up to a certain extent ofcourse. I guess I'll have to live with it and see if the garage can fix it on the next maintenance, unless the seals of the pump or any other seals than the injector seals are easily replaced at home?

 

Have a Nice weekend! Cheers