Longtime TTAC Commentator KeepAustinWeird writes:
Hi Sajeev, I’ve got a 2000 SAAB Viggen with 113K miles. Recently, I’ve noticed that after I’ve been driving the car for about 20 minutes and the car is good and warmed up, the motor totally bogs until I can get to 3,000 RPM, at which point the car takes off. This is particularly annoying (unsafe) pulling away from full stop, where I either have to gun the motor or crawl thru 1st and part of 2nd before the RPMs rise enough for the boost to kick in. Wondering if this is a MAF (which I’ve cleaned) issue, a drive by wire sensor issue, or a dying turbo issue?
Sajeev answers:
That’s a tough one to armchair from the Internet, unless you spend hours on SAAB forums. That said, I suspect several trouble spots for late model turbocharged applications: fuel starvation, Engine Computer trouble code, exhaust/turbo leak or a vacuum leak. I don’t see a turbocharger failing this early, unless oil changes and abuse are a problem. Then again, abuse a Viggen mid-corner and you’ll be kissing a whole lot of Austin hill country. And have far more pressing issues than engine bog.
You cleaned the MAF (and I’ll assume you checked for trouble codes) so my money’s on a vacuum leak. Do the easy stuff first: a complete visual on the rubber/plastic/whatever lines, especially around the fuel pressure regulator, if applicable). Check every hose that starts from the intake and snakes every which way, and, if needed, get under the car to spot look for cracked, split or blown hoses specific to the turbo/intercooler. Most modern vacuum systems are more than just rubber hose, so if a forum doesn’t give enough diagnostic info, punt and go to a SAAB wrenchhead.
Another possible concern: the lack of fuel. When did you last change the fuel filter? If it’s been over 30,000 miles, that’s too long. If that doesn’t help, check fuel pressure while driving: rent a long-hose fuel pressure gauge from a parts store, connect at the testing location (usually the fuel rail) latch (but don’t close) the hood, drive and compare the gauge’s numbers to factory specs and DIY for free. If the pressure is below spec at idle or drops under full throttle, the pressure regulator or fuel pump need to be tested.
Good luck with all that.
[Send your queries to mehta@ttac.com]
My 9-3SE did this. Have you tried cleaning the throttle body? There was an ECU issue on the 9-3 (not sure about the Viggen) that saw the DI cassette and throttle body get pretty badly fouled.
After 113K miles you’ve probably already replaced the DI cassette a couple times, but it may be time for yet another one. My far less sexy 9-3 coupe did that a couple of times, and a new DI cassette fixed it right away.
I’ve just fixed a vacuum leak on a 4-cyl 9-5, no dramatic symptoms besides lugging into boost sluggishly as you described. It did throw a check engine light pretty immediately though.
Pardon the ignorance… DI cassette?
Pardon the ignorance… DI cassette?
Welcome to the World-O-Saab, where, if things can be made more difficult or expensive, they will be.
Hence the direct ignition cassette, or as it’s known to Saab people, a way to milk you into changing the whole ignition system, up to and including the spark plugs, in one cash-bleeding shot.
You thought VW’s coil packs were bad? DI cassettes seem to go only slightly more often than brake discs.
it is actually now a ICM, not a DIC anymore. Guess they got tired of the jokes. They come in red and black. If you have a red one in there it is for the older systems and will cause problems. The black ones are supposed to be more reliable. Be wary – there are now Chinese clones out there. Use some dielectric grease when putting the DIC back on the spark plugs. DIC failures usually throw out an engine code.
If it isn’t throwing out an engine code, might be some sort of emissions issues. I had one that would stutter around and turned out to be a bad purge valve.
Another possibility is related to limp home mode.
The SAAB bbs are pretty well run; older cars are getting more rare and it is harder to find answers but everyone wants to save their viggens.
Another vote here for the DI cassette. But before you drain your bank account for that repair, check your plugs for proper gap. You’d be surprised how often this is the only problem.
Plugs need to be regapped, or at least checked, on a regular basis. Failure to do so can contribute to early DI death.
If you replace the plugs, you MUST use the proper NGK plugs, no other brands, no other substitutes. These are very specific resistor-type plugs. The wrong plugs will also kill your DI cassette.
A note here: This DI cassette, though unfortunately troublesome, is part of a Saab engine management system that was waaaay ahead of its time.
Also, the red DI cassettes are more reliable than the black ones, which your 9-3 most likely has. Black DIs are growing a bit scarce too.
But anyway it’s just your plug gap.
For a more experienced list of diagnoses, and to find out how wrong we all are here, go to the NG900 forum at http://www.saabnet.com.
Great stuff B&B, keep the thoughts coming! Yes, SAABs can be a bit of a PITA in the maintenance department but I just love this Viggen to death. The thing has real soul in a jellybean car world, and it’s practical as hell.
I’m the third owner of my Viggen but I was able to get a nearly complete maintenance history printed off at the local stealership. I’ve been taking the Viggen (and my 9-3SE before it) to a local, independent SAAB shop.
The DI cassette was done a few years back but it may be time. The one in the car is the black one. I have looked for vacuum leaks but haven’t spotted any. No idea what plugs are in the car or how long they’ve been there. I will probably start there.
It’s just so odd to me that the car runs so strong when cold, but then bogs after it is all warmed up.
It’s just so odd to me that the car runs so strong when cold, but then bogs after it is all warmed up.…
Not a SAAB guy, but often when cars run well cold but become troublesome when warm, it is because cold engines run in “open loop”, that is the ECM ignores many sensor inputs and runs on pre-programmed “maps.” Once the engine is warmed up, as determined by the coolant temperature sensor (or some other derivatives of a temperature sensor) the ECM starts to depend on sensor inputs. This is “closed loop” operation. If some of these inputs are screwy, the driveability goes out the window. The ECM also goes into open loop under WOT (wide open throttle) conditions. Don’t know if this pertains to the SAAB in question…
Yeah I was going to say to try that Swedish Automotive shop off Lamar across the street from the Chinatown shopping center.
Yup… check those NGKs gap and the throttle body. Dosent sound like a misfire though…then fersure thered be codes. Next, make sure the wastegate and servo arent sticking/blown and all those vacuum hoses are connected/not leaking.
Bomber991 – that’s the shop I take the Viggen to, Swedish Auto. Honest shop and Omar knows his SAABs. When I do have to take the car in for service, at least I know I’ll have a really great meal across the street ;-)
You guys are killing me. I miss Austin. :-(
C’mon over, Sajeev! You can drive my Viggen and give me your thoughts. As for Austin, what I usually tell people is that I don’t live in TX, I live in AUSTIN. Those who know, “get it”. Like you obviously do ;-)
FYI, Austin recently became more interesting to gearheads b/c a new track has opened called “Driveway”. I haven’t been there yet but it looks quite good. Check it out at http://www.drivewayaustin.com/
As a long-time Saab guy, I do not think this is the DI cassette. Having had a couple go bad over the years, they really tend to be “all or nothing” – you start having a mis-fire that gets worse and worse.
Now down in TX this time of year, could it be good old heat soak? The air intake plumbing and intercooler get heated up in stop and go traffic and responsiveness goes right out the window until enough air gets passed though to cool things down again. The engine management dials back the boost and the ignition timing to prevent detonation from the super hot intake charge. BTDT in my Saabs, and it can make for a “moment” pulling out into traffic. Is this your first summer with the car?
As to the fuel filter – with the GIGANTIC Bosch fuel filters in these cars, changing them even at 60K miles is probably overkill unless you buy your gas from Muddy’s Gas Station. In the my new 9-3SC, the fuel filter is smaller than the old one, and is integrated into the fuel pump and not replaceable. And this seems to give no issues.
In general, vacuum leaks will make for general rough running, this seems too specific.
Khrodes1 – indeed, this is my first summer with the Viggen and I have suspected that the ridiculous, sustained summer heat is the culprit. Or at least a prime suspect. Though, I didn’t experience anything like this with my previous 2000 9-3 SE with the HOT. I do plan on dropping in new spark plugs. Far as I can tell from the maintenance records I inherited, the plugs were last changed at 68.5K miles at the stealership and the car now has 115K miles on it.
Just joined this site today… couldn’t resist finding out if keepaustinweird is the OTHER lightning blue ’99 Viggen in Austin?? If so, please kindly repaint your car so that mine is the only one :) Kidding of course. Pretty awesome to have multiple Viggens in some a “small town” like Austin. I’ve also seen a grey one and possibly a yellow one. Anyway, this thread caught my eye because I’m having a VERY similar issue with my Viggen for the past 2 years. Basically, the overall symptom is that my Viggen has lost its mojo – here’s some more info (sorry about the length).
– Turbo doesn’t really engage until almost 3,000 RPM
– When it does engage, it seems to engage slowly and not the super pull that it used to have, except that sometimes it surges (like keepaustinweird said)
– Just replaced DI cassette, and car has been serviced regularly; I believe I got new fuel filter at 90K service
– Took it to a couple of shops over the past year and they said they couldn’t find a vacuum leak (I still secretly believe that replacing all hoses would solve the problem); one of the places I took it to was Swedish Auto (Omar)… but honestly, it’s hard to be driven to find a performance problem in a car that is still faster than most things out there… but if you’ve ever driven a Viggen, you honestly never forget. In 2nd, it used to be a challenge to keep on the road – it’s pretty easy to keep on the road nowadays :( And the turbo used to feel like I was doing something illegal – now it feels quite legal
– Factory turbo gauge (which is really a MAF gauge) goes almost all the way through the yellow, but there’s still a sliver of yellow left – I believe this is normal for stock Viggen
– Installed after-market boost gauge and it gives me about 10 psi (in 3rd or higher). If I really time it right and push the car, I can get 12… I think I’m supposed to get 10-14 psi pretty easily at sea level, and up to 20 psi at higher altitudes
– Installed K&N filter and steering brace and rear bar – no other mods
– It idles at around 950 when cold, and maybe 1,050 after a drive. The idle is a bit jumpy, but not severe enough to register on the tach… but I definitely feel the slightly varying vibrations during idle
ANY assistance would be greatly appreciated. I have been trying to track down this problem on and off for 2 years now. I just want my Viggen back!!!
PS – If replacing a part is going to cost less than about $200, I would rather just replace the part than to perform time consuming diagnostics (of course, I am open to quick diags) – for example, Crankshaft Position Sensor, maybe even the MAF… BPC too?
PPS –It’s a ’99 Viggen with 104,000 miles. Performance issue has existed for 2 years and I don’t know what caused it. Never been in accident.
Wish I had a dyno so I can prove to the shops that the Beast is now a pussycat. Any help appreciated.
AustinViggen – just seeing your post now so apologies for the delayed reply. I actually have a 2000 5-door Lightning Blue Viggen, not a ’99. Supposedly it is the only 5-door LB in Texas. Seen your car at Swedish Auto.
Just in-case any other Viggen owners with a similar issue comes across this, I wanted to provide closure. The culprit? The ECU. Swapping the ECU made the difference. The original ECU got so sick it didn’t even throw codes anymore. Now I have a wild beast of a Viggen. Couldn’t be happier.