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Discussion Starter #1
Alright guys, I normally figure most everything out myself but this has me stumped and will take thoughts from the field, my pride of the fleet 1999 stage 2 w/130k on the clock is slow to start, it's like an old Chrysler ! given that a few items hadn't been replaced yet, I did the fuel pump ahead of schedule and the CPS at the same time. Both were going to need replacement anyway. No change. Figured I would put on a new DIC to see if it would make any difference, it didn't (put the new one back on the shelf). vacuum hoses are new, and spark plugs (platinum) only have 13k on them gap good. Tested the compression slightly low 140-157 dry. So what am I missing ? it does the same hot or cold, even 5 minutes after it was running. It's not a battery thing, turns over quick and fast, just to rule those questions out.
 

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To be clear, you're saying the starter spins at a normal speed, it just takes a lot of cranking before it fires up?
 

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Discussion Starter #3
correct, probably 10-13 seconds of cranking before firing where all others are 2 maybe 3 seconds.
 

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Yeah, that's (obviously) unusual. Have you tested the fuel pressure regulator and check valves at the pump? Does the pump prime when you turn the key for the first time?
 

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Discussion Starter #5
I didn't test the actual pressure, It was doing the slow start thing before changing to a new pump and yes it primes right up and shuts off prior to actual starting, waiting 10 seconds after turning the key doesn't seem to matter, once operating no starvation at all through any gear or load. it's a puzzler. I'll test for ACTUAL pressure though.
 

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*Sounds like* a failed check valve, but could also be a bad FPR. WIS describes a residual pressure test to measure... I don't know what it is offhand, but it should help you determine whether either or both of these are suspect. IME, these are THE cause for long cranking on Saabs going back to c900s.
 

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Discussion Starter #7
I have a couple sets of new ones so I could throw them in, didn't feel like messing with the lines when I changed the pump but any new parts gets me closer to a new car.
 

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does the T7 have an adaption process after being reset? A couple of times I noticed that after disconnecting battery for different reasons, the car started a couple of chugs sooner when reconnected.
 

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Maybe give a quick spray of starter fluid and see if it fires right away or not. That should point you towards or away from fuel pressure.

A noid light on the injectors to be sure they are firing would confirm that CPS is working.

Check the wire harness grounds under the intake, pretty sure those are important to ECU.

Is the throttle body clean? You'd probably have idle issues as well if it did not close properly but you never know.

Really reaching - how are O2 sensors? Any chance one is sending bad signals and confusing ECU?
 

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I wonder if this might have something to do with the TB in regards to the internal tps? Maybe the tps is failing and giving off false readings??
 

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I wonder if this might have something to do with the TB in regards to the internal tps? Maybe the tps is failing and giving off false readings??

This could be checked really quickly with an OBDII tool. I've never known a TPS to cause starting problems unless it was WAY out of adjustment.
 

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does the T7 have an adaption process after being reset? A couple of times I noticed that after disconnecting battery for different reasons, the car started a couple of chugs sooner when reconnected.

Not exactly, no, but this car is a T5 (1999) car, so no electronic throttle actuator anyway. :)
 

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Discussion Starter #13
Okay so here's the follow up, best to close this out and give a resolution so others can know I didn't just junk the car because of a small issue. So I swapped out the check valves at the pump/tank what a pain in the #%&#! who thought that was a good idea without a connector ! . doing this made a slight difference is time of cranking but only slightly while I waited for the new fuel pressure regulator to come in. Testing the FPR showed 43lbs upon initial priming before cranking, but only for a few seconds then it bleeds right off down to about 6lbs defiantly the issue. Put in the new Bocsh FPR and it holds at 43, and starts 1.5-2 seconds ,,back to the way it should be. Sometimes you can't see the forest thru the trees. Thanks for all the input. I now have a spare for the others so I won't have to wait for shipping.
 

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FPR strikes again!

The first time this happened to me in the '90s I really started questioning my fuel injection diagnostic chops. A Saab mechanic friend said, "Dude, it's the FPR" (he did not say that, he was VERY Austrian) and sold me a new one. SOLVED.

The fuel pump check valves are a royal PITA, but they're designed to prevent you from being engulfed in flames during a crash or rollover, so I suppose they serve a purpose. OTOH, the one time I rolled a Saab I kinda wished I'd died - I loved that car. Maybe a fiery death would be ok.
 

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It's one half of the equation... You need the FPR at the other end of the line to hold pressure, otherwise pressure just leaks out through the open end.
 
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