SaabCentral Forums banner

1 - 20 of 36 Posts

·
Registered
Joined
·
21 Posts
Discussion Starter #1
So i have this strange issue for two months i think. Car fails to start from the first time but starts right up from the second time with no problems. It feels like it is just about to start and dies.. This happens only when the engine is completely cold. And for the rest of the day there is no problems.. I have tech 2 and there is no problems i can think of and all parameters seems right. The only thing i can see that short term fuel trim on idle is about +7-+10 so just maybe there is small vacuum leak but i guess it won't affect the start of the engine so much.. Saab wis states up to +12 it is normal..

So far what i did:

New mass air flow sensor - genuine new,
New o2 sensor genuine bosh,
New CPS sensor,
Checked fuel pressure with gauge all seems normal and it holds pressure.
Checked fuel pressure regulator also seems normal.
Tried running fuel pump with tech 2 for 20 seconds before starting still first time not started..
Cleaned injectors with brake cleaner and spray pattern was good before cleaning..
Engine compression was tested few months ago and it is good.
Di cassette was bought new about an year ago OEM so i think it is good and no check engine lights flashes or constant light..
Sparks look good oem ngk changed about 7000km ago.
Also tried to spray a little bit of starting fluid and it starts from the first time, but again it doesn't show what is wrong with the car..

What do you suggest checking further?
 

·
Registered
Joined
·
214 Posts
Since it starts first time when using starting fluid it is most likely a fueling issue. I've heard that sometimes the fuel will leak past the check valve in the fuel pump causing this issue. BTW, I have the same exact problem but mine won't start even with a spray of starting fluid. But, it always starts on the second or third time.
 

·
Registered
Joined
·
21 Posts
Discussion Starter #3
if it would be fuel check valve or fuel pump the pressure will drop when testing but it is not dropping.. Again as i said i can run fuel pump 30 seconds before cranking engine with tech2 but this doesn't help.. Today i also tried disconnecting both evap hoses going to intake manifold and cobra. Tomorrow i will see if that helps..
 

·
Registered
Joined
·
21 Posts
Discussion Starter #4
ok i got some progress.. yesterday disconnected two evap hoses going to throttle body and cobra and plugged them.. also disconnected brake booster from intake manifold and also plugged manifold.. Today the car started with no problem.. So if it starts tomorrow it will be one of two things. A - EVAP valve is broken and letting petrol fumes into intake manifold and first time the mixture is too rich to start the car or B the brake booster or it's lines are creating vacuum leak and car fails to start.. I think more probably it's bad EVAP system.
 

·
Registered
Joined
·
602 Posts
Instead of engaging the starter, for first start of the day try turning the headlights on and leaving them on for about 30 seconds. Then turn the lights off, wait for about five minutes, and try starting it. If it starts on the first try after this procedure, it suggests that the problem might be related to an aging or discharged battery. By turning the lights on, it activates the battery (counterintuitively) and then there is sufficient voltage to fully engage the starter and the rest of the ECM system.
 

·
Registered
Joined
·
21 Posts
Discussion Starter #6
Instead of engaging the starter, for first start of the day try turning the headlights on and leaving them on for about 30 seconds. Then turn the lights off, wait for about five minutes, and try starting it. If it starts on the first try after this procedure, it suggests that the problem might be related to an aging or discharged battery. By turning the lights on, it activates the battery (counterintuitively) and then there is sufficient voltage to fully engage the starter and the rest of the ECM system.
Battery is 1 year old and was fully charged about a week ago.. Its 100% not a battery as it spins the engine like it should. I said that today it's started and there is two options EVAP or Brake booster vacuum leak.
 

·
Registered
Joined
·
602 Posts
Well that settles that in your case. Maybe LD rider can give it a shot with his problem.
Battery is 1 year old and was fully charged about a week ago.. Its 100% not a battery as it spins the engine like it should. I said that today it's started and there is two options EVAP or Brake booster vacuum leak.
 

·
Registered
Joined
·
1,256 Posts
Purge valve, which is part of EVAP system, is normally closed and opens with 12v signal from ECU. It allows fuel vapors stored in EVAP charcoal canister to enter TB via engine vacuum. (On 9-3s it is at the front of engine and really easy to get at. Not sure about 9-5.) Usually a stuck open purge valve causes hard starting and rough running at idle for a bit especially after refueling since liquid gas displaces vapor in the tank and pushes it through the system and into the TB causing a rich condition. If you have a vacuum pump (EZ Bleed or similar) check that the valve holds vacuum when engine is off. Connect vacuum pump to valve port that goes to TB. If it doesn’t hold vacuum then it’s open and allowing excess fuel vapor to enter TB during cranking.
 

·
Registered
Joined
·
101 Posts
I have been chasing down the exact same problem, and have done almost everything you have done as well, save I went ahead and replaced injectors rather than cleaning the old. I havent had much time to work on this so I have been doing little things over a few months. Its been long enough now that I have a new pattern:
The issue started last spring 2020 (here in mid Atlantic USA) so when temps got warmer, the starting issue appeared.
Now, without resolution, its fall and winter...as soon as temps got down below 60 degrees daily average I have had no starting issues...Fires up everytime first attempt.

I got to same point thinking it was something in Evap system, but never started tracing it.... now that cold weather has solved issue... I dont know if that helps diagnosis or not? Some folks have sworn that the winter and summer gas mixtures here in US can be culprit.... My guess has always been a rich situation at start....

good luck. will be interested to see how it goes!
 

·
Registered
Joined
·
180 Posts
I have been chasing down the exact same problem, and have done almost everything you have done as well, save I went ahead and replaced injectors rather than cleaning the old. I havent had much time to work on this so I have been doing little things over a few months. Its been long enough now that I have a new pattern:
The issue started last spring 2020 (here in mid Atlantic USA) so when temps got warmer, the starting issue appeared.
Now, without resolution, its fall and winter...as soon as temps got down below 60 degrees daily average I have had no starting issues...Fires up everytime first attempt.

I got to same point thinking it was something in Evap system, but never started tracing it.... now that cold weather has solved issue... I dont know if that helps diagnosis or not? Some folks have sworn that the winter and summer gas mixtures here in US can be culprit.... My guess has always been a rich situation at start....

good luck. will be interested to see how it goes!
The same thing is happening to me. About two months ago, my car developed an issue where it would stall out and die on the first start of the day. After that it was fine for the rest of the day. This lasted about a month, now it starts up fine just fine. I have no idea why, but I am not complaining.

I have a p0456, very small evap leak, which I thought may have been related to the problem. Tried for two weeks to find it, but was not able to. Even made a smoke machine. If you let it run long enough you can see some smoke seep out of the throttle body/intake manifold area. The throttle body o-rings are new, I'm assuing it was leaking out of the pcv fitting area. I am not sure if that would set off the evap code.
 

·
Registered
Joined
·
21 Posts
Discussion Starter #11
Ok so today it didn't start from the first time again.. as somebody suggested i tighten up filler cap but as evap is disconnected i see no way how this can help.. We will see how car behaves tomorrow and try something new to fix it..

If you have any ideas please share..
 

·
Registered
Joined
·
101 Posts
Im sure you have searched other similar threads. So this may not be anything news, but I have come across a few folks attributing this to the type of gas. In the US there are two mixtures of gas: "summer gas". and "winter gas". Apparently a few people suggest that depending upon what mix is being sold this can happen. This is NOT about octane ratings. My problem started when it got warm and summer gas was being sold. My problem went away when winter gas started being sold at the pump. I use almost exclusively Exxon or Shell.

This seems hard to really believe but its worth considering and I am open to it being the case, and maybe I need to change away from exxon or shell in summer?

Deividas, I am color blind so its hard for me to see what order green and red is in your flag, if there is even green and red... Is that Lithuania? Apologies for my bad eyesight. regardless, do they do a similar summer gas and winter gas mixture???
 

·
Registered
Joined
·
21 Posts
Discussion Starter #13
Im sure you have searched other similar threads. So this may not be anything news, but I have come across a few folks attributing this to the type of gas. In the US there are two mixtures of gas: "summer gas". and "winter gas". Apparently a few people suggest that depending upon what mix is being sold this can happen. This is NOT about octane ratings. My problem started when it got warm and summer gas was being sold. My problem went away when winter gas started being sold at the pump. I use almost exclusively Exxon or Shell.

This seems hard to really believe but its worth considering and I am open to it being the case, and maybe I need to change away from exxon or shell in summer?

Deividas, I am color blind so its hard for me to see what order green and red is in your flag, if there is even green and red... Is that Lithuania? Apologies for my bad eyesight. regardless, do they do a similar summer gas and winter gas mixture???
Hmm i don't really know why it should be gas as it starts and runs really fine from second try.. Yes i live in Lithuania and mostly use premium brand gas like Neste or Circle K.. Past 5 years i had no issues with gas so it's really strange.. I still have a list to check but i can check only one thing every day..
 

·
Registered
Joined
·
8,454 Posts
Do you have tune?
If yes, replace it with Saab original sw and report back.
I have met 2 or 3 9-5 (2002-2003) which have tune and they acted same.
 

·
Registered
Joined
·
21 Posts
Discussion Starter #15 (Edited)
Do you have tune?
If yes, replace it with Saab original sw and report back.
I have met 2 or 3 9-5 (2002-2003) which have tune and they acted same.
Yes i have a stage1 but problems started even before i made a tune.. This tune change only max value of air mass and have nothing to do with ignition or start maps.. But maybe will add to my list..

UPDATE: Hmm interesting i found this option called catalyst light off which changes some parameters on cold start and also retard ignition to heat up catalytic converters faster.. Maybe i fixed my original problem but with this tune there is another problem.. I will definitely try to rewrite back original tune. But on stock file this option is checked so i don't know still going to rewrite back original file..
 

·
Registered
Joined
·
21 Posts
Discussion Starter #16
Ok reflashed firmware to the stock but still first time cranking took a longer time and it almost starts and dies.. Second time it starts from the half a turn..

Now what i did is closed lpg tank valve and disconnected vacuum hose from the lpg reducer and now going to see how it starts with no lpg gas in it..
 

·
Registered
Joined
·
8,454 Posts
Now you tell your issue: LPG.
Forget all and remove all LPG parts and put original back.
 

·
Registered
Joined
·
21 Posts
Discussion Starter #18
Now you tell your issue: LPG.
Forget all and remove all LPG parts and put original back.
It was running fine 5 years i only changed reducer to the higher output.. It's just a theory about lpg i completely flushed all gas from the engine so if it doesn't start tomorrow then lpg gas is not the problem..
 

·
Registered
Joined
·
8,454 Posts
Why you swap reducer back, if car was running OK with old one?
 

·
Registered
Joined
·
21 Posts
Discussion Starter #20
Why you swap reducer back, if car was running OK with old one?
Maybe i explained wrong.. Reducer was swapped about two years ago for a more powerful. Everything was running fine until about two months ago..
Today i couldn't start it from the first time again, so if it won't start tomorrow i will rule out lpg gas.. There isn't many things to check more.. Next are injector orings and plugs..
 
1 - 20 of 36 Posts
Top