Saab 9-5 2.0t auto saloon 2001
Discussion
Nice to come home this evening and see the delivery from Neo Brothers waiting for me. The car had been driving pretty well again today although still has the hesitation under heavy acceleration along with misfire readings on the open SID when it happens.
I got home and it seemed half my family had decided to visit but I said a quick hello before going out to fit the new parts. I'd opened the bonnet as soon as I got home to help cool the engine before I worked on it but as it was the DI cassette and recirculating dump valve there shouldn't be too much heat in these parts.
I knew the DI cassette would come out easily enough as I'd taken it out last week to change the spark plugs and hoped the dump valve would be just as easy. I was pleased to get the hose clips off easily and the pipes pulled off the dump valve without too much effort.
The new parts were an easy fit - just the 4 star head screws and electrical connector for the DI cassette and 2 hose clamps and the push on vacuum hose for the recirculating dump valve.
I had a look at the old parts - the dump valve looks OK but I can't find a definitive guide as to how to test if it is broken. If I suck on the hole where the vacuum pipe attaches it initially lets no air through then when I suck a little harder then I feel something move inside (the diaphragm?) and am able to suck some air through it.
More interesting was the DI cassette. Despite me not seeing any cracks or damage to it when I changed the plugs and even tonight the tube attaching to cylinder 3 looking all OK I did see the end tube is in poor condition with half a tip of one of the tubes actually missing:
Can't believe I missed that as now it looks so obvious! I do wonder whether it had a crack in it and part fell off after I removed it as it looks so clear to see now but who knows. I was looking for cracks between the turrets when I last removed the DI cassette as most advice I have seen says to check there but I should've known to have a really good loot at the tubes as well. Schoolboy error.
I got home and it seemed half my family had decided to visit but I said a quick hello before going out to fit the new parts. I'd opened the bonnet as soon as I got home to help cool the engine before I worked on it but as it was the DI cassette and recirculating dump valve there shouldn't be too much heat in these parts.
I knew the DI cassette would come out easily enough as I'd taken it out last week to change the spark plugs and hoped the dump valve would be just as easy. I was pleased to get the hose clips off easily and the pipes pulled off the dump valve without too much effort.
The new parts were an easy fit - just the 4 star head screws and electrical connector for the DI cassette and 2 hose clamps and the push on vacuum hose for the recirculating dump valve.
I had a look at the old parts - the dump valve looks OK but I can't find a definitive guide as to how to test if it is broken. If I suck on the hole where the vacuum pipe attaches it initially lets no air through then when I suck a little harder then I feel something move inside (the diaphragm?) and am able to suck some air through it.
More interesting was the DI cassette. Despite me not seeing any cracks or damage to it when I changed the plugs and even tonight the tube attaching to cylinder 3 looking all OK I did see the end tube is in poor condition with half a tip of one of the tubes actually missing:
Can't believe I missed that as now it looks so obvious! I do wonder whether it had a crack in it and part fell off after I removed it as it looks so clear to see now but who knows. I was looking for cracks between the turrets when I last removed the DI cassette as most advice I have seen says to check there but I should've known to have a really good loot at the tubes as well. Schoolboy error.
Edited by DanG355 on Thursday 11th October 22:34
Once it was all fitted (total of about 10 minutes) I had a small window of opportunity for a test drive before I had to mingle with the family. A quick run around the block confirmed no misfires, strong pulling through the rev range including with the throttle wide open. I could only test it up to about 55MPH due to the local roads and could only do a short run but things are looking good.
The drive to work tomorrow will give me a better opportunity for a full test. I'll also take some pictures of the new dump valve in place in the daylight rather than in the dark now.
The drive to work tomorrow will give me a better opportunity for a full test. I'll also take some pictures of the new dump valve in place in the daylight rather than in the dark now.
I’ve driven the car a lot today and it’s close to being all good, but not there yet...
It pulls hard from low revs and goes really well but under full throttle at about 5k revs there’s a stutter and misfire on cylinder 3 code is showing on the open SID again. Turbo sounds quite loud and has a whooshing noise but as it’s pulling well I don’t think it’s a boost leak, but air mReq is still higher than mAir on the open SID so it’s a possibility.
I’ve got a busy weekend ahead but will check the spark plug gaps again especially cylinder 3. If I get time I’ll look for any sign of a boost leak but this might have to wait. It is only under full throttle that the gap between air mReq and mAir is there but could still be something. I got a mate to video the air readings and interestingly with mReq over 1,000 the mAir doesn’t get above 850.
It pulls hard from low revs and goes really well but under full throttle at about 5k revs there’s a stutter and misfire on cylinder 3 code is showing on the open SID again. Turbo sounds quite loud and has a whooshing noise but as it’s pulling well I don’t think it’s a boost leak, but air mReq is still higher than mAir on the open SID so it’s a possibility.
I’ve got a busy weekend ahead but will check the spark plug gaps again especially cylinder 3. If I get time I’ll look for any sign of a boost leak but this might have to wait. It is only under full throttle that the gap between air mReq and mAir is there but could still be something. I got a mate to video the air readings and interestingly with mReq over 1,000 the mAir doesn’t get above 850.
2gins said:
Hi Dan, cheers for posting this. Reading with interest as I have a 9-3 Aero and I'm sniffing around 9-5s, no reason other than I have the 3 yr itch and I like a fast wagon.
Some advice on the power issue, having had a 1.8T TT for 6 years and taken it to stage 1.5. Those 1.8T engines are quite susceptible to boost leaks and as you've mentioned as soon as you start driving boost up you will expose any weakness in the whole air metering, mixture, spark and vacuum system. If the car is not 100% then you can expect problems unless you have some very good luck. Best thing you can do is a leak test, loads of videos on youtube and all you really need are some plastic fittings, a tyre valve, some hose and a foot pump. This is the fastest and lowest cost way to find a boost leak and avoids switching out part after part. After that its air flow, in the world of VAG 1.8Ts it is MAF, MAF, and MAF again. They're generally hot wire sensors and they foul up over time, have it out and clean it by soaking it in a polythene bag with contact cleaner. Replacements are north of £100 for the 9-3 but it is worth doing. They will read good enough for the OEM conservative tune but weaknesses will be shown up by higher boost (more air flow in). As a rule of thumb airflow/0.8 = engine power so it you're looking for 220 then flow should be > 170 g/s.
With the VAG-com diagnostic software the acid test was always a WOT run in 3rd/4th from 1500 rpm to red line and log the live values for airflow, requested boost, actual boost, and ignition advance on all cylinders. I don't know if you can do that with the Saab (I haven't bothered looking into it myself). This would usually show up boost management issues and air starvation. For best running on those engines the golden rules were:
Healthy MAF
Healthy plugs
Healthy coils (DIC in your case)
Clean air filter
No boost leaks
99 RON fuel
If any of these are weak on the VAG engines either you won't be making boost or the engine will pull timing to reduce knock; if it needs to pull more than I think 12 degrees advance it will limp.
I can't speak for the GM engines but on the basis that all turbo engines work pretty much the same way the areas to look at are probably not much different. Karl seems like a good guy and pretty much the Saab opposite No. to the guy I gleaned all this VAG stuff from, so I expect you're in good hands. But as ever, start with the basics. Leak test, good ignition side, then start trying to rule out weak spots.
I'll keep reading!
Thanks - I appreciate the tips. The DI is new so I'm ruling that out and the difference in air requested and actual air makes me believe it is a boost leak somewhere or possibly a MAF issue but won't know until I solve it.Some advice on the power issue, having had a 1.8T TT for 6 years and taken it to stage 1.5. Those 1.8T engines are quite susceptible to boost leaks and as you've mentioned as soon as you start driving boost up you will expose any weakness in the whole air metering, mixture, spark and vacuum system. If the car is not 100% then you can expect problems unless you have some very good luck. Best thing you can do is a leak test, loads of videos on youtube and all you really need are some plastic fittings, a tyre valve, some hose and a foot pump. This is the fastest and lowest cost way to find a boost leak and avoids switching out part after part. After that its air flow, in the world of VAG 1.8Ts it is MAF, MAF, and MAF again. They're generally hot wire sensors and they foul up over time, have it out and clean it by soaking it in a polythene bag with contact cleaner. Replacements are north of £100 for the 9-3 but it is worth doing. They will read good enough for the OEM conservative tune but weaknesses will be shown up by higher boost (more air flow in). As a rule of thumb airflow/0.8 = engine power so it you're looking for 220 then flow should be > 170 g/s.
With the VAG-com diagnostic software the acid test was always a WOT run in 3rd/4th from 1500 rpm to red line and log the live values for airflow, requested boost, actual boost, and ignition advance on all cylinders. I don't know if you can do that with the Saab (I haven't bothered looking into it myself). This would usually show up boost management issues and air starvation. For best running on those engines the golden rules were:
Healthy MAF
Healthy plugs
Healthy coils (DIC in your case)
Clean air filter
No boost leaks
99 RON fuel
If any of these are weak on the VAG engines either you won't be making boost or the engine will pull timing to reduce knock; if it needs to pull more than I think 12 degrees advance it will limp.
I can't speak for the GM engines but on the basis that all turbo engines work pretty much the same way the areas to look at are probably not much different. Karl seems like a good guy and pretty much the Saab opposite No. to the guy I gleaned all this VAG stuff from, so I expect you're in good hands. But as ever, start with the basics. Leak test, good ignition side, then start trying to rule out weak spots.
I'll keep reading!
The new valve arrived today although haven't had time to fit it:
The car is running mush as it was - fine under light and medium load and heavy throttle at low revs, but stutters if you floor it at higher revs. It seems better in Sport mode but no idea why that would be as I believe it just makes the gearbox kick down easier and adjusts the throttle sensitivity.
I noticed the Nood ECU means the MPG readings on the SID are no longer any good. When resetting the MPG after filling up and pulling away from the petrol station the reading went from blank straight to 25PMG and stayed there for a while before adjusting to 25.4MPG. I would expect this to be around 18MPG shen setting off around town based on experience so far and rise to 30-ish if driven sensibly. Interestingly though the DTE (distance to empty) does seem about right and adjusts well depending on how you drive.
The car is still a pleasure to drive despite the stuttering issue and when in traffic listening to music with a coffee in the cupholder and nestled in the comfy seat I feel all I am missing is a pair of slippers. I'm sure my heart rate is lower in the Saab than when I'm at home.
As the weather was so good for October yesterday I took the other car to work for the commute and after a clean at the garage I got some nice pics on the way home:
I noticed the Nood ECU means the MPG readings on the SID are no longer any good. When resetting the MPG after filling up and pulling away from the petrol station the reading went from blank straight to 25PMG and stayed there for a while before adjusting to 25.4MPG. I would expect this to be around 18MPG shen setting off around town based on experience so far and rise to 30-ish if driven sensibly. Interestingly though the DTE (distance to empty) does seem about right and adjusts well depending on how you drive.
The car is still a pleasure to drive despite the stuttering issue and when in traffic listening to music with a coffee in the cupholder and nestled in the comfy seat I feel all I am missing is a pair of slippers. I'm sure my heart rate is lower in the Saab than when I'm at home.
As the weather was so good for October yesterday I took the other car to work for the commute and after a clean at the garage I got some nice pics on the way home:
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