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Discussion Starter · #1 ·
My 1987 900 turbo starts just fine cold. I took it to grocery store last night and was inside for 15-20 minutes, returned to the car and it would just crank and crank without turning all of the way over. Smelled of fuel in the car. Let it sit for about 15-20 more minutes and then cranked until it started, just turned the ignition for about 30 seconds and it finally caught and I drove home. I tried to start it this morning and voila it started just fine. But I am worried that it will not start again if the engine is warm. Any suggestions? Crank position sensor seems to be the most common culprit. I know that the fuel pump is fine, I can hear it start when I turn the ignition. And when the car starts it runs just fine, except for at idle it has started idling at 1100 rpm instead of 800 rpm.
 

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Discussion Starter · #2 ·
Also I have found that the vacuum hose from my shift up solenoid was disconnected and the plastic hose connector was broken off. I put a golf tee in in its spot so no gunk or grime will deposit in the hose.
 

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The symptom you describe is a textbook description of a failed Fuel Pump Check Valve. It's easily verified with your fuel pressure gauge.
 

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Discussion Starter · #4 ·
Found a fuel pump check valve, actually two. One is 10mm inlet and the other is 12mm inlet. How do I know which one to order without tearing it out. I just drove 40 miles round trip and the car idled at 2000 rpm's a couple of times and when I got home I shut it off and started it again twice with success.
 

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You might wanna check the "5th fuel injector" too , AKA , the cold start injector.
I had the same issue on my 86 Turbo. I replaced the NTC coolant temp sensor and cleaned the battery terminals too.

Joe.
 

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Discussion Starter · #7 ·
I suppose it could be the temp sensor. The battery terminals are good. From what it sounds like the fuel pump check valve is a pain the rear to install. replacing the temp sensor might not be a bad idea, I think that it is safe to assume most of my Saab is factory.
 

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The symptom you describe is a textbook description of a failed Fuel Pump Check Valve. It's easily verified with your fuel pressure gauge.
My car always starts, but it needs to crank for more than a few seconds before it starts. However, when I crank it a few seconds, turn off ignition, then crank for second time it starts almost instantly. Is this also a fuel pump check valve issue? thanks,
 

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Your fuel pressure gauge will tell you whether or not the check valve is working. It's silly to guess what part you need, then try it. That's not how diagnosis is done. It would be even sillier to guess what part you need, then replace a different one because it's easier.
 

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I suppose it could be the temp sensor. The battery terminals are good. From what it sounds like the fuel pump check valve is a pain the rear to install. replacing the temp sensor might not be a bad idea, I think that it is safe to assume most of my Saab is factory.
Yea , it would be a good idea. Buy a Bosch one , I purchased one on "eEuroparts" , shipping took forever , but for 16 bucks it's a decent price for a quality part.

Skim around the web for another parts source , I found the same Temp sensor for cheaper afterwards.

It was pretty straight foward too , the sensor is on top of the engine , make sure you have a drain pan or cardboard underneath , because It'll cough up some coolant once it's removed.

Good luck! :)

Joe.
 

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87 has the old fuel pump, not the new plastic ones. do they have a check valve?

Edit: Nvm, looks like they are metal instead of plastic

Try checing the Fuel filter as well. I had this problem and the filter was clogged.
 

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Discussion Starter · #12 ·
I had a golf tee in a vacuum line for the up shift indicator solenoid, or at least that is what I thought it was, it is located on the drivers front fender outside the engine bay. Anyways I removed it last night and it is running just fine now, I checked all the small vacuum lines as well just in case and they all seem good, pinched them all or removed them from their inlets and it would sputter. I will give it a couple more runs before I call it finished though. Thank you for all the input.
 

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I suppose it could be the temp sensor. The battery terminals are good. From what it sounds like the fuel pump check valve is a pain the rear to install. replacing the temp sensor might not be a bad idea, I think that it is safe to assume most of my Saab is factory.
Don't replace temp sensor, just unplug it and see if it runs better.
 

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Discussion Starter · #14 ·
It is running just fine. I took out the golf tee out of the shift up indicator solenoid and everything went back to normal.
 
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