Mobil1 TDT 5W-40, 4799 mi, 1999 Saab Turbo

[MO]

1999 Saab 9³ 2.0L Turbo (185hp base model)
Mobil1 Turbo Diesel Truck 5W-40
See here for last report:
http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Board=3&Number=897692

And here's the results:

As a note, in almost all of these, although I added no makeup oil, the engine did use about 1/2 quart over the 5000-mile interval.

First reaction: this engine definitely likes the Delvac1 oil (in whatever marketing package) better than GC, which is a great compliment, because it wasn't bad on the GC. Check out the previous results (link above) for a full history back to my first UOA, which shows a test with M1 0W-40. That M1 was a great oil too, I'm sure, but the GC clearly outperformed it, so I'm really happy with the D1.

Still, not everything is perfect. Copper went up a couple UOAs ago, and it still hasn't come all the way back down. Silicon is a little on the high side. Last oil change, I replaced my K&N air filter with an OEM paper filter to see if that helped, but as you can see, there was no change. The silicon is not a high number, but I can't explain why it's higher than it used to be, and it's on my mind as long as copper is on the high side.

The startup noise I mentioned in my last UOA post has gone away on its own. Not sure if it's related to the change in oil type--probably just a random thing.

The fuel dilution is probably from changing the oil before getting the engine good and hot. I warm it up a bit before changing the oil, so the oil can flow better, but I don't get it fully hot. Avoiding burning myself is more important to me than getting an accurate measurement of fuel dilution in my UOA.

I changed the oil, and since I had 5 quarts of GC left (including the first two green I've found) I put that in. I plan to run it this OCI and then switch over to D1 (or maybe the new D1 ESP?) permanently.

Matt

 

[JAG]

Engine one of the sludge year models? Still clean looking inside from what you can tell? If so to both questions, I'm very impressed.

The oil choice looks to be working well. IMO the fuel dilution can't be blamed on the warm-up and sampling technique...just seems like too much fuel to be added in such a short time. I don't know much of this engine but I expect turbo engines to be fuel diluters in order to avoid detonation during high load. Not to say it can't maybe be improved some with making sure the key parts (plugs, ignition, fuel injectors, PCV system) are in tip-top shape.

 

[MO]

This engine was before the sludge problems. The last time I had it open was at 60,000 miles (now 105,000), and it was spotless inside. I've used nothing but M1 0W-40, GC, and D1 since then, with 5000 mile OCIs, so I'm hoping it's still just as clean.

As you can see, fuel dilution has been all over the place over the last few UOAs. I changed out a bunch of PCV parts at 90,000, and I changed the spark plugs and ran Techron Concentrate at 90,000 and again at 100,000 (I do these every 10k). Dilution did go down in the OCI after each of these, but I wouldn't say I have enough data to be statistically meaningful. No work at 105,000 besides the oil and filter, so we'll see what happens during this OCI.

Can anyone explain how fuel generally gets into the oil? I understand if you have bad rings and you get blow-by, but I'm not burning much oil, so I don't think I have that problem. The ignition system retards ignition if necessary to prevent knock; as far as I know, it doesn't enrich the mixture (unless it runs a little rich in general). What are the factors that contribute to fuel dilution?

Thanks for the thoughts,

Matt

 

[StoicDude]

Since you have about the same results as I did with my car, I figured I ll chime in to let you know what I did and how my numbers improved across the board.

I changed my fuel filter at 60 000 miles, vacuumed my airbox and the air filter and started using FP3000.

All numbers improved. Silicone and copper were the big improvements, which had the same pattern as yours. going up/ staying constant at a high ppm level without any changes in driving etc.

I will have to see what happens on my next UOA, to get a more consistent answer.

 

[BrianWC]

Just as I've said on SC, the 5W40 TDT AND RTS are a good call in our SAABs

 

[saaber1]

Hi Brian WC,

Can you please tell me which saab engines are the sludge-prone ones? I am considering buying a very well maintained 99' 9-5 base 4cylor maybe some other newer saab. I've had tons of the pre-94 900's and quite a few 9000s but have been out of the saab cars for quite a while. Thanks!

 

[BrianWC]

That's one of them.

1999-2002 9-5 2.3l
1999-2002 Viggen 2.3l
2000-2002 9-3 2.0l

I am currently on a 2001 9-5 2.3l with more than 120k miles. Thanks to keeping current with the PCV upgrades, dropping the oil pan and clearing the pickup screen, and a few runs of auto-rx, I have had absolutely no worries. If I were you, I'd at least ask for maintenance records. Early on, a lot of owners were getting dealer oil changes at 10k miles with synth blend. This was killer in these particular engines. But even a large amount of owners who did nothing but shorter interval synth changes have had an issue or two. I got mine sorted out quick, though, and it's been a pleasure to own....

 

[CosmicFlash]

Originally Posted By: saaber1
Hi Brian WC,

Can you please tell me which saab engines are the sludge-prone ones? I am considering buying a very well maintained 99' 9-5 base 4cylor maybe some other newer saab. I've had tons of the pre-94 900's and quite a few 9000s but have been out of the saab cars for quite a while. Thanks!


If you can spend $8-10,000 you could find a nice 2003 9-3SS which was a new design for the 03' MY.
Mechanically it's a great car but very advanced electronics so some issues there. Go to SaabCentral and look at the threads there.

 

[saaber1]

Isn't that car an opel vectra with a saab engine? Drove the opel in Europe and it was [censored]. Don't know much about those other than I like the looks in some trims... the vector or aero or whatever they call it looks really nice. I got away from saabs when they became all gm-gooey. Drove a 97 900 SE the other day and the understeer on that thing was simply unbelievable and was night-and-day different from the classic 900. I hope those newer ones shed some of that horrid "gmness".

Drove a 99 9-5 and it felt very nice and volvo-like and reminded me of the old 9000s mainly due to the size. But I only drove it around the block and didn't take it through any turns. I will see what newer 9-3s are avail. here locally and maybe give one a test drive. Thanks for the heads up on those.

 

[MO]

saaber1,

The new 9-3 (2003+) and the Vectra (2002+) are both based on the GM Epsilon platform, along with the Chevy Malibu, Pontiac G6, Saturn Aura, and Cadillac BLS. However, the Saab is in no way a re-badged Opel.

Saab and Opel shared the design lead for the Epsilon platform specification, so they both got what they wanted included in the platform. This defines some basic things like how and where various parts of the car attach to each other, but two cars on the same platform need not share many, if any, parts. A platform is a conceptual idea of how a car goes together, and it allows different cars to pull some parts from a shared bin to save costs when the engineers want to use those parts. The Saab and the Opel are very different cars, though. The suspensions use different components--you'll notice the wheelbases, for example, are different.

The only car that shares significant components with the 9-3 is the Caddy, which is really a re-badged 9-3 built in Sweden for the European market.

The classic 900 was the last Saab you'll ever see that was truly an independent design--and in fact, there are few cars in the world that are independent any more (BMW, as their ads point out, is one). But that doesn't mean there's anything wrong with the new Saabs (or Audi, Volvo, Lamborghini, or most other cars).

So go enjoy a test drive in a 9-3. I think they drive pretty nicely, although I've never pushed it hard enough to see whether it understeers at the limit the way mine does (you must have driven that 900 pretty hard to see the understeer...). Handling is definitely crisper, with more responsive steering and less torque steer.

Oh, and if I were shopping for another car now, a 9-5 Aero wagon would be near the top of my list.

Matt

 

[RI_RS4]

Copper seems to track the elevation in silicon around 90K miles with a one OCI lag. You've also got some killer Fuel Dilution going on. I think StoicDude is right on track. Take his advise.

 

[MO]

RI_RS4,

I agree that the two could be correlated--but as I wrote, I recently changed the air filter, putting in a new OEM paper filter, which is what I was running when the silicon was low. Silicon didn't drop back down, though.

I have also been running Techron Concentrate every 10k miles. From reading the forums here, there doesn't seem to be any suggestion that FP is significantly better than Techron Concentrate.

I'm not sure what else StoicDude has done that I haven't. Keep in mind, too, that he's driving a different car--he has the VW 1.8T, still a turbo 4, but that's about where the similarities end. I agree that StoicDude made some good suggestions, and they worked well on his car, but since I've already done the equivalent, I think there's something else going on here.

Still curious--anyone have a good explanation of where fuel dilution comes from?

Matt

 

[JAG]

My explanation, which may only be partly correct, of how fuel typically gets in oil is:
1. Fuel in cylinders during combustion condenses on oil film on cylinder wall which then gets scraped back into the sump by the rings
2. Fuel-laden combustion products leak past rings during combustion stroke (blow-by)

In addition to the critical engine parts I mentioned above, some other potential causes of increased fuel dilution are (this is based on my VW 1.8T engine so some of these may not apply exactly to your engine):
1. Short trips (where short is less than ~20 miles of driving per start up). Just reaching ideal oil temp is not enough to evaporate off the fuel that built up prior to that point. Getting enough evaporation is both time and temp dependent. This is unfortunate in that driving longer distances or making extra trips to reduce fuel dilution costs money and may not be worth it.
2. MAF sensor coated in oil/varnish/dirt. Spray it with MAF sensor cleaner. Coated MAF can affect air/fuel ratio. Might as well clean the throttle body too to make sure its motion isn't restricted by filth.
3. Out of spec first O2 sensor. This has similar effect with coated MAF sensor.
4. Intake air temp sensor coated in varnish/filth. In the 1.8T, it is after the intercooler. Don't know about yours. Clean it with MAF sensor cleaner or similar solvent.
5. Out of spec coolant temp sensor. ECU may "think" engine is still in warm up mode which may affect air/fuel ratio and ignition timing
6. Stuck thermostat. Can be stuck anywhere in its range.

 

[RI_RS4]

Originally Posted By: MO

I have also been running Techron Concentrate every 10k miles. From reading the forums here, there doesn't seem to be any suggestion that FP is significantly better than Techron Concentrate.


Matt, one advantage of FP3000 or RLI BioPlus is the increased lubricity you see in every tankful of fuel. You do not get this benefit with Techron every 10K miles.

 

[MO]

JAG,

Thanks for the reply. My assumption is that abnormally high blow-by is primarily a result of bad rings, and that along with it you would normally see some oil consumption. Hopefully, my low consumption means that this is not really an issue.

That leaves fuel condensation on the cylinder walls as a way of it getting into the oil. Again, making an assumption, I would guess that this is increased by incomplete combustion, which could be the result of an over-rich fuel mixture. Therefore, your second list of causes is primarily a list of reasons for an over-rich mixture. I like your suggestions about cleaning the MAF and IAT sensors and the TB--I'll probably do all of those this spring after the weather improves a bit. I'm pretty sure, based on not experiencing typical Saab symptoms of coolant temp sensor and thermostat trouble, that I don't have to worry about those for the moment. And you're right about the short trips--my commute is 6 miles each way, and while I do take the car on longer trips from time to time, I don't remember if there had been a long trip recently when I did this oil change.

Based on your first post in this thread, though, it sounds like you think that the short-trip driving alone wouldn't account for the amount of fuel dilution, so I'm still thinking that the sensors and TB could use a cleaning.

RI_RS4,

Good point on the lubrication. It just seems like a real hassle to add FP to every tank. Do you know if there's something that can be added every 5k or 10k miles to help with fuel system lubrication?

Thanks,

Matt

 

[BrianWC]

MO, how long has it been since you changed the plugs or the DI cassette?

As for short tripping, our cars run pretty darn rich regardless. Short tripping is just going to magnify that issue. Perhaps off on a tangent, but have you done a good combustion chamber cleaning? You're bound to have a pile of crud on your piston crowns. As for the TB, I haven't seen too many b204s with TBs that bad off.

Sigh....wishing I still had my 97 SE turbo.....

 

[Saab9-3]

By combustion head cleaning do you mean Chemtool 12 or whatever its called. and Cheers from SC

 

[BrianWC]

Yep. About a capful per plug hole. May ultimately not have a major effect but it's nice to do every now and then.

 

[JAG]

Hi Brian. What's the procedure? Pour a capful per plug hole while engine is still hot or do it when engine is cold and let it sit for X hours before starting the engine?

 

[BrianWC]

The engine is better off kinda cold. Otherwise, the Chemtool with boil off as soon as you pour it in. The best way to do it is to pull the fuel pump fuse and then turn the car over until the gas is out of the lines. Then pour Chemtool in and let it sit. It really doesn't have to sit a LONG time. I seldom have the patience to wait more than 10 minutes. Chemtool is pretty dang strong. Anyway, then go ahead and crank the car again a couple of times to flush the chemtool out and then reinsert your fuel pump fuse. Then crank again until she runs. With just a cap full (well maybe a TAD more) per cylinder, you don't risk hydrolocking. You still may have a cloud of smoke after you get things back running, but having the fuel pump fuse out minimizes this as well as misfiring.

One thing to note on SAABs-extended cranking runs our batteries down VERY quickly. Once when I got a little overly generous with the chemtool I had to use a jumpstarter pack to get everything going again. Another reason to be sparing with the Chemtool.