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Discussion Starter #21
Yes, the engine is running with too much fuel and therefore tries to reduce it by adaption.
Has battery been disconnected after other fuel pressure regulator has been installed to reset adaption values?
Yes, the battery has been disconnected a few times after changes were made to the configuration. The P1300 and P0172 codes come back consistently.

there was another thread were there was suspicion that vacuum could/might pull fuel over EVAP tube. It would make sense in that way that in vacuum conditions you get much more fuel, adapt to -25..-50% and as soon as you enter boost area there is no more addtional fuel, but adaption still reduces fuel by 25...50%, which is too much, engine goes lean and stalls.
If long term adaption also applies during start (I am not 100% sure about that) better starting behavior with disconnected tube is also explainable: usually you would have 3 bar differential pressure, but with disconnected tube you will have 3.5....3,8 bar, resulting in square root (3,5/3) or square root (3,8/3) 8...12% more fuel which partyl compensates -25% long term adaption.

Proposal for further tests:
1. check fuel pressure (although they might be ok). engine running, tube disconnected, should read 3bar.
1b. check for residual pressure. engine stopped, turn ignition on, fuel pressure should jump to 3 bar, turn ignition off, fuel pressure should very slowly drop to minimum 2.2 bar within 20 minutes, if everything is ok it remains nearly constant within an hour. this could rule out dripping injectors.

2. disconnect EVAP, put a short rubber fuel tube on the throttle connector, plug the open end with a screw, fix the screw with clamp. Take care that the lose EVAP line does not interfere with the belt. disconnect battery for 60s to reset adaptions values. check driving again.

3.
check oscillating front O2 sensor again. In first post it was ok, but fuel trim were both?? around 0, later on both fuel trims -25, O2 sensor still oscillating or flat at 0,7..0,8V. (Although I do not see a direct connection between working and defect O2 sensor and boost/vacuum conditions). (Just in case: do not use any contact spray on the O2 sensor connector, it will destroy the sensor).
I'll check all of the above tomorrow, these are definitely worthwhile suggestions.
 

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Discussion Starter #22
Checked the codes again when I got there, he had driven it around a bit and only had P1300 and P0172 codes still. I checked all the ground points I could find, they looked shiny. Not a hint of corrosion on this car's electrical. I pulled the EVAP hose and plugged the manifold fitting, still had a hard time starting. In fact I couldn't get the car to stay running at all today, and I forgot to bring my fuel pressure gauge! The pump runs and fuel sprays out of the schrader valve on the rail when you poke it, but I'm not sure of the actual pressure. The engine always dies within two seconds of starting. No misfires, just shuts off. Ran the battery down a few times and I'm not sure what has changed from the last time to cause it not to stay running anymore. Before it would idle as long as you wanted it to. I'm bringing my scope and fuel pressure gauge next time.
 

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make sure to reset adaption values by disconnecting battery. It is still not clear if bad adaption values influence start fuel amount. If you have P0172 adaption is at -25% limit.
 

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Discussion Starter #24
Yes, because the battery was run down from excessive starting attempts I removed it from the car to charge it several times.
 

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People think I am crazy but when my turbo from a car I had recently bought was dangerous, would slow right down going on hills, no boost not even yellow - I removed front part of exhaust from turbo to the catalyst converter - I gave a small knocked on it with a hammer tapped around a bit, and a inch chunk of platinum honey comb came out, Then I poured into the pipes to clean the converter unit inside a mix of citric acid powder (heaps) and water and soaked in the bath tub over night. Swished it about in the morning and hosed out fully to clean not soapy, and when reengaged with car - turbo came to life to redline. Yesterday i replaced my regular end length of the exhaust pipe (3 meters long!)with one from an Aero. the only difference I can see is the very end one foot long cap of the exhaust is maybe wider or straighter but it actually makes a difference now to the boost character.It's a little smoother and maybe faster even. I think your issue may be respiratory.
 

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How do you check fuel pressure with tech2?
Valve timing is fixed on this engine, there is no advance and retard in valve timing nor in air/fuel requirement.
Only ignition timing can be advanced and retarded.
There should be a PID for fuel tank pressure.
Didn't think to clarify since the b235 only has one cam profile and no phasers= no VVT.. I obviously meant ignition timing. The T7 engine management system requests precise amounts of air and fuel which is relative to the ignition timing
If timing is off, stretched chain, a link skipped a gear tooth- whatever the case is- similar issues will develop.

With that said testing should begin with the basics. That's just sound automotive diagnostic procedure. When people start throwing theories around it can end up costing people money and wasting their time.. no matter how how helpful one is trying to be. Test the basics first. Air, fuel, spark. Get a vacuum gauge hooked up and verify your 15-20 in.hg, check ALL hoses and gaskets are tight and the intercooler isn't cracked somewhere, clean the MAF with proper cleaner, pull the plugs and take a peak at the piston crowns, they shouldn't be sparkling clean unless you've run a fuel system cleaner recently.. and on and on.

With an issue like this the basic diagnostic tools are an absolute must. Most can be rented from an auto parts store.
Any number of things could be the issue. Chain skipped a tooth/ broken tooth on a gear somewhere, poor spark from a bad DIC, vacuum leak, fuel pump (likely, but a gauge should be used to verify), poor compression in a cylinder, etc...
Edit.. again,

Everyone's giving good advice in my opinion but just be careful your not jumping from system to system without ensuring each one is functioning at it's optimal degree first.
Also, its not uncommon for a fuel pump to still give some amount of pressure. So when the testing ports valve is pressed something will still come out. It may even run UNTIL it needs to really spin up.. then it'll conk out. It's sounding like a pump failure with a possible vacuum leak at this point.. you may have more than one issue going on.
 

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But there is a difference between vacuum pressure in tank and fuel pressure in the rail. The pressure sensor in the tank is just for evaluation that the EVAP system works properly. There is no relation to fuel pressure.
Since we get too much fuel, it is unlikely that the fuel pump does not deliver enough pressure.
Let´s wait what the fuel pressure measurement shows, although change of fuel pressure regulator has not solved the problem in the past.

Another idea would be again check for air leakages, but it has already been done.
Quick test, depending on available tools:
disconnect MAF rubber tube from cobra pipe.
put a rubber glove (for sealing) and a bigger piece of cloth (to prevent the rubber glove from exploding) on the cobra pipe, fix both with a clamp.
plug crankcase ventilation pipe (between cobra and crankcase ventilation sytem) at the end (or disconnect it at cobra pipe and let someone put his big thumb on it for testing). (If you have old cobra with thread you could try to find a fitting screw, but it is metric with a finer thread, unlikely to have something like this available in the workshop)
open oil cap a little bit
use small tube from cobra to turbo valve (disconnect at turbo valve) to very gently fill the system with an air gun, if possible with reduced pressure of 0.5 bar.
If you could attach a pressure gauge in the system, pressure should drop very slowly, otherwise just check for hisses and air coming out somewhere.

Car also runs too rich if you loose already measured air. To loose air, it should have higher pressure than ambient, which is downstream compressor. Upstream compressor it would suck in additional air, running too lean.
With higher boost level you will loose a lot of air, which could result in the shown behaviour.

Problem is, that you have already inspected it and even running without MAF does not help.
 

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Discussion Starter #28
Hey, I haven't been able to get down there because of the riots and curfews, and we still can't get it to stay running. I told him to try unplugging the MAF but if I can't get there I'm kind of out of ideas. What could be causing it to start up, run smoothly for 1-2 seconds, and then stall, every time?
 

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Hey guys this is based and Saab-pilled 1DollarSaab's friend who bought this Saab story. Current update on what we've been seeing :

-Fuel pressure tested, showing over 40 PSI after priming but the fuel pump doesn't run and the fuel pressure drops as soon as the car starts

-Checked the fuel pump relay under the kick panel, relay is good but behind the kick panel we found some shady work, looks like another relay was spliced in to the yellow, red and blue wires. Pics attached.

Looks like something with the TWICE, like they were trying to bypass it? Hopefully someone with more familiarity with T7 security issues can chime in?
273743
 

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They tried (or obviously succeded) to bypass the starter relais.
Which does not make sense as you cannot start the engine if key is not accepted as it will not open injectors. Otherwise immobilizer would be too easy too fool.

Do you get a message in SID: key not accepted?

Does the needle of tachometer moves just a little bit when it cranks? Otherwise it might be an indication that crankshaft sensor is bad. It would require original Bosch as a replacement.

Fuel pump is primed for one second at ignition and shoud be restarted as soon as engine speed is recognized. Bad crankshaft sensor --> no engine speed signal --> no fuel pump.
As priming is ok, electrical path to fuel pump should be ok.
Engine might start from priming from priming fuel pressure but than stalls when fuel pressure drops.
 

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They tried (or obviously succeded) to bypass the starter relais.
Which does not make sense as you cannot start the engine if key is not accepted as it will not open injectors. Otherwise immobilizer would be too easy too fool.

Do you get a message in SID: key not accepted?

Does the needle of tachometer moves just a little bit when it cranks? Otherwise it might be an indication that crankshaft sensor is bad. It would require original Bosch as a replacement.

Fuel pump is primed for one second at ignition and shoud be restarted as soon as engine speed is recognized. Bad crankshaft sensor --> no engine speed signal --> no fuel pump.
As priming is ok, electrical path to fuel pump should be ok.
Engine might start from priming from priming fuel pressure but than stalls when fuel pressure drops.
The car has 2 keys, one is accepted with "CHECK OK" and the other says "KEY NOT ACCEPTED."
 

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As soon as the other oroblems are solved you should try to get the other key running. Having only a single working key might become a bigger problem as soon as it fails.
But this is another topic.
What about the tachometer needle?
 

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Tach is behaving normally. It starts as I said but loses fuel pressure within seconds causing it to shut off.
 

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Discussion Starter #36
Then try to measure voltage at fuel pump to separate between electrical supply fault and pump fault.
The pump runs when you turn the key on and it primes the system normally, without fail. It stops running after the engine starts. Something is turning off the power to the fuel pump.
 

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Do you have the possibility to measure voltage?
Then it would help to measure voltage (against chassis ground) at output of
1. Input at pin 30 of relay 102 (fuel pump)
2. Input to coil at pin 86 of relay 102
3. Output at pin 87 of relay 102 (easier at fuse 19 upper connector)
3. Output at pin 87 of relay 229 (main relay) (easier at fuse 7 upper connector)
Maybe main relay is switched off and it will not only shut off fuel pump by relay but also complete trionic including DIC and fuel injectors.
Maybe previous owner also did some modifications on relay 229?

next cheap test in parallel (or before):
supply battery voltage directly to fuel pump:
open fuse board on driver side and remove fuses 19 and 8 and make connection between fuse 8 upper part to fuse 19 lower part.
This should run the fuel pump permanently without any relay or fuse.
A bended paper clip might do the trick if no appropriate cable with connectors can be found.
Remove paper clip a running fuel pump will drain the battery if tests are finished.

check output of fuse 27, it should have and remain battery voltage as soon as key in ignition position and during start.
If this fails it will shut off trionic, opening relay 229 and therefore shutting off power supply to relay 102.
This might point to ignition switch although I do not see a reason why running/starting engine would cause ignition switch to fail, other than vibration??
 

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I've had a very similar sounding set of symptoms on my 2003 9-5. The accursed intermittent fuelling fault. I finally diagnosed the problem by putting an ammeter in the fuel pump circuit, and saw that the current dived to a low value (but not zero) when the fault appeared. Changed the pump. fault went away. The cause was a partially-broken-up commutator in the pump motor. Sometimes it ran fine, sometimes it didn't. Needless to say, the faulty pump was a cheapo replacement, not a SAAB original. Lesson learned.
 
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