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2000 93 Vert Auto : 2001 93 Vert Manual
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Discussion Starter #22
Well, I think I might have got the problem solved. I don't think just one thing fixed the problem, however.

Executive Summary: I believe the main culprit was either a dirty Throttle Body or an ill-seated Charge Air Pipe.

Background: This car used to live in Virginia and was donated to a charity organization in Greensboro, NC and I bought it from the organization in Cary, NC. The car had been sitting for several months at the charity.

To summarize: The problem started when I did the PCV update and changed the Vacuum Hoses. I did these at the same time. While changing the vacuum hoses I noticed that the Brake Booster Vacuum Valve (BBVV) was broken, probably by me while replacing the Vacuum Hoses, so I ordered a new Brake Booster Vacuum Hose assembly and installed it. While installing the BBVV I removed the big plastic Charge Air Pipe that goes to the Throttle Body so that I could replace the red nipple assembly at the Vacuum Pump that attaches to the cam as it had broken when removing the hose (I later discovered I did not need to remove the Charge Air Pipe or replace the nipple assembly - I just needed to put the red piece from the new assembly into the existing assembly - that’s a whole other story).

What I did in the mean time: Replace the Fuel Filter, replaced that battery as it would not hold a charge and, lastly, cleaned the Throttle Body.

Without a doubt, changing the Fuel Filter and Battery helped the way the car ran. I thought maybe the problem was fixed. But alas, no.

When I went to clean the Throttle Body it looked dirty to me with much black soot around the edge of the butterfly valve as well as beneath the valve. When I reinstalled the Charge Air Pipe it seemed to fit a little different, so I am not sure if it was cleaning the Throttle Body that did the trick or maybe I didn’t have a good seal at the Charge Air Pipe.

Over the last two days I have been out doing my best to get the car to misfire with no success (thankfully). Hopefully I can lay this to rest.

If it were the Throttle Body causing the issue, I am curious as to why the PCV Update would cause the Throttle Body to start acting-up.

Thank you everyone for the help and feedback.
 

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Discussion Starter #23
I posted too soon.

It stuttered a few times today and almost cut off at an intersection. I took it on a longer drive with highway and city driving and the more I drove the less it stuttered.

There is a big difference in the way the engine feels when it is in park or neutral vs. drive - I don't know if that is normal or not. When I was having issues at the intersection, putting the car in neutral seemed to stop the problem.

I will keep looking for the issue, but for now I can drive the car and I don't feel that the stutter is going to leave me stranded. To be on the safe side, I moved the spare Chinese DIC from my car to this car - just in case it is the DIC.
 

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If there is a mixture or idle control problem, it will definitely be worse in drive than in park or neutral, so that makes sense.
 

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Any chance there's another hose on the TB that is cracked or loose... that would explain why it came up after you worked on it. Or perhaps there's a seal issue with one and driving/heat/expansion seals it up? Or maybe even an intake manifold gasket leak and you leaned on the TB while doing the work, causing a leak?

How about doing a smoke test? There are plans on youtube for making your own for a few dollars. If you can't find them, I have a link here somewhere. There's a mechanic who specializes in home built and demoing use of them.
 

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Discussion Starter #26
Thanks for the feedback. I will check for loose bolts over the weekend.

I have suspected that the outside temperature is playing a part in how the car runs. It was in the low 50's this morning and I started the car with the OBD2 reader attached. It ran rough and threw a code. P0300.

When using my OBD2 software on cold starts first thing in the morning I have noticed that the air temperature sensor for the engine is reading higher than the outside air temperature. Today it read 62.7 when the real temp was in the low 50's - so it has been reading 7 to 10 degrees warmer than the real temp. When I do the same cold start for my car, my car is reading almost exactly the same temp as the actual outside air temperature.

I was going to switch the sensors, but between 2000 (the one having issues) and 2001 (my Saab) they changed the sensor setup. The sensors are not the same and they are not even in the same place.

Here are my observations over the past few weeks:
Mid 50's or below the car will throw a code and run rough when starting. Stumbles a good bit when driving.
Mid 60's the car will stumble occasionally when at idling in gear or under minimal load but starts fine. No issues when accelerating.
Mid 70's and above the car runs without issue and is nice to drive.

I have a new sensor on order but it will not be here until Monday. Fortunately the temperature will be in the high 40's on a few mornings next week so I will be able to see if it makes a difference.
 

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Just one more thought... since the car started running rough after some work and it might be temp related, how about checking the wiring and the connector? Perhaps clean the connector?

I recently had a confusing SRS issue to solve. All came down to a bad connector that looked OK with a quick check but some very minor corrosion caused it to have high resistance and throw errors... all from just moving the wire around while working in that area. Perhaps you did the same with the temp connector?
 

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I have zero clue about the 9-3. but the 9-5 ,with the cable controlled hybrid pcm driven throttle body. that can give trouble. If removed and cleaned, and not replaced correctly, with the actuator set properly, you can run into issues. In your case, replacing the PCV and related vacuum lines, you figured out how brittle the hoses become and just working in that area can break stuff. I suspect that some of your issues are self inflicted. In my case, correctly diagnosing a faulty throttle body ( the PCM driven module on the side of it was bad) and replacing the throttle body unit with new, we ( my electrical guru and myself lol) incorrectly set the limp home mechanism, and the car set codes for fuel pump relay and MAF, driveability was weird, on start up the engine flared up to 2800 rpm before settling back down, and occasionally the car would quit running altogether, and would only restart if I cleared codes. All of these codes were misleading by themselves. Once the throttle body was correctly reset, all codes disappeared, etc.

I have zero clue if this experience applies to the 9-3 specifically, other than the advice that vacuum leaks cause these sorts of issues, and fault codes point to the area of fault, not necessarily unit replacement of a specified part. As BobSaabit pointed out, connectors are a significant issue. And smoke testing is #1 in my book for diagnosing faults. My Mac Tools smoke tester cost a lot of money, but its worth every penny...
 

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Discussion Starter #30 (Edited)
It was 40 degrees this morning so I hooked up the OBD2 reader to both Saab SE's to get a cold start comparison.

I will continue to look for vacuum leaks as well as loose or bad connections.

Whatever the issue, it is related to outside air temperature. When I had the car inspected the mechanic noted I had a leaky exhaust flex pipe and I read that could confuse the O2 sensors.

Here are the big differences I noticed in the OBD2 readouts, but I don’t know what the data means. The Long Term and Short Term Fuel Trims seem to be the most out of whack.

The 2000 is the car with issues.

Air Intake temp:
2000: 46.5
2001: 41

MAP PSI:
2000: Started at 14, spiked down to 10, spiked back up to 14 and slowly went down to 7.
2001: started at 14, leveled off at 10 then gradually dropped to about 7

Long Term Fuel Trim:
2000: Constant at 9.4%
2001: Constant at 3.1%

Short Term Fuel Trim Bank 1:
2000: 0 for over a minute then climbed to 20%
2001: Start at 0 with a quick dip to -18% and a gradual rise to 8%

Timing Advance:
2000: Quick spike to 8 then quick drop to -8 and then a spike to 0 about the time it threw a code, down to -10 tor about 45 seconds then up to 10
2001: Start at 6, drop to -6 to-8 for awhile then a climb to 9
 

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Discussion Starter #31
I just drove the car around with the OBD2 connected to try to get the engine to stutter. At the end of the drive I checked the engine codes and had a pending code of P0336 - Crankshaft Position Sensor range / performance problem. Unfortunately I have no way of knowing if this pending code corresponds with the engine stuttering.
 

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Discussion Starter #32
I cleared all codes and took the car out again. Once I got it to stutter it showed another pending code of P0336 - Crankshaft Position Sensor range / performance. I guess that I am going to need another Crankshaft Position Sensor.

Note that this does not show up with the check engine light and is not detected by my OBD2 reader unless it is hooked up while I am driving. I should have done this a long time ago.
 

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I think you found your stuttering issue - bad CPS. Get a Bosch sensor. I don't have enough experience to know which of the other readings is correct with the exception of a comment on the fuel trim: I believe that's a lot of correction... and I know for sure an exhaust leak is a problem. The o2 will read wrong. When it gets bad it will start to throw an O2 code. But I could definitely see it messing up performance long before that. the O2 sensor is important in trionic.
 

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Definitely. That's an uncommon failure mode on a Saab, but it's not for CKP sensors in general. Make sure you buy the correct Bosch sensor or you will be back here in a few months.

You MAY have another issue - those fuel trims suggest a lean mixture. But one thing at a time.
 

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Discussion Starter #35
I replaced the Crankshaft Position Sensor (CPS) and I think that may have solved the issue. I got another P0300 right after I installed it (and changed the the air temp. sensor and the fuel pressure regulator). However, the car seems to be running fine now with no stuttering. I have since started it when it was 45 degrees with no issues at cold start - something that would have previously thrown a code or caused an erratic/rough idle. When driving with the OBD2 device connected I am no longer getting the P0336 code.

Replacing the CPS was a real PIA. Getting the T30 screw out (and back in) that keeps the CPS in place and holds the cover was very challenging as I was having to work without being able to see the screw. To get the screw back in I had to use my screw picker-upper tool to hold the cover in some semblance of the correct position.

Heres the important part:
I used three layers of paper towel to hold the screw tight onto my T30 socket, otherwise it would have slipped off and caused me no end of suffering - this took a good bit of experimentation using a variety of materials. Paper towel works better than leaves, electrical tape, painters tape, pieces of rubber gloves or regular paper. I will remember this for the future.

The OEM sensor wire was clipped to something else that I could not reach, so I had to cut it off and leave a piece of abandoned wiring on the car. Something for the next owner to ruminate about.

Thats the thing about working on these cars - I can often see the bolt/screw, but can not get a tool on it.
 

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While working on these cars is sometime challenging at best, the old method of removing more than needed is the better approach. Also have a small ratchet that holds screwdriver bits works well for tight spaces. Removing the down pipe makes the job simple, and if you take the down pipe off often the bolts don't end up breaking on you later.Add up the time spent struggling vs. disassembly would outweigh the aggravation. On the upside you learn how the whole car comes appart.
 

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Glad to hear it looks cured.

I'm with MultiSaab: Pulling the downpipe off makes this job a heck of a lot easier. It's STILL a PITA, but it's a little easier. Also, replace that little bolt with a stainless one, maybe a stainless hex, and anti-seize the threads. That way you can get it out next time. If you didn't, put that on your list.

Pulling off the DP should probably be PM on these cars... do it before that day you have to do it... and put fresh nuts on for when you do need to. That way everything comes off when you need to do a repair. Nothing is worse than having to do a job that needs the DP off and finding that you need to spend an hour or more dealing with rusty studs and stuck nuts. The T7 is the worse of the two motors with that nut underneath & shielded by the upper cat on stock cars. Well, OK, there are some things that are worse, but that's one that's annoying.
 

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While working on these cars is sometime challenging at best, the old method of removing more than needed is the better approach. Also have a small ratchet that holds screwdriver bits works well for tight spaces. Removing the down pipe makes the job simple, and if you take the down pipe off often the bolts don't end up breaking on you later.Add up the time spent struggling vs. disassembly would outweigh the aggravation. On the upside you learn how the whole car comes appart.
I'll second this, although there is a very good youtube video for doing the CPS without removing anything else. Stuck? Pull more parts off lol. You'll get better at it.

From my own experience: P0300, barring vacuum issues is either the fuel pump (check valve), fuel filter, DIC or CPS. In my case the rough idle was greatly improved with a new DIC and the remainder will be fixed when I get the fuel pump done later.
 
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