Surging / rough idle <-- throttle body problem SOLVED!! - SaabCentral Forums
*
Home Saab Pictures Saab Classifieds Saab Dealer Listings Saab Forum Saab Forum


Go Back   SaabCentral Forums > Saab 9-5 Mk.I, 1998-2009 > 9-5 Workshop

9-5 Workshop 9-5 Workshop (1997 to 2010) Technical Forum

SaabCentral.com is the premier Saab Forum on the internet. Registered Users do not see the above ads.
Reply
 
Thread Tools Display Modes
  #1  
Old 20th September 2006
DriverEd DriverEd is offline
Senior Member
 
Join Date: Aug 2003                                                
Location: Toronto, Canada
My Saabs: 2005 9-3 ARC CV, 2000 9-5 SW 2.3lpt
Posts: 240
Default Surging / rough idle <-- throttle body problem SOLVED!!

Finally, this irritating problem that I've been getting all summer is solved!!
History here

Update:
- I ended up getting the throttle body re-programmed instead of replaced. It drove great for about a week, then I got the surging problem again came back for one day, then disappeared just as quickly. A few days later I got a CEL and "TCS OFF" light on but it drove fine.

- So I ordered a used throttle body from a salvage yard ($200CAD shipped) and installed it in less than an hour, including clean-up and test drive. (thanks to dip's guide.) The dealer was charging $780CAD for a new one - no thanks.

Result: Everything drives beautifully now - even after several short drives (which used to trigger the surging problem). And as a side benefit, for some reason I am getting MUCH better gas mileage with this TB. I used to average about 11L/100km on my daily commute. Now I'm down to 9.9L/100km !!! Anybody care to explain why?

In any case, I'm a happy camper now! Thanks to SC for all the help as usual!

Ed
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2  
Old 20th September 2006
aikman7981 aikman7981 is offline
Senior Member
 
Join Date: Sep 2006                                                
Location: hawaii
My Saabs: 2000 9-5 Aero sedan, 2.3T auto
Posts: 161
Default

I just went through the same procedure on my 2000 aero. dealer tried to tell me to have the TB replaced but thanks to these forums I told him to reprogram it. I surely hope I don't have to have it replaced as you did b/c I am much less competent mechanically than you. I would wind up getting towed to the dealer to then pay the $700 or so to replace the TB. Was your DI replaced immediately prior to the TB problem? I believe the two to be linked but cannot prove it.
Reply With Quote Quick reply to this message
  #3  
Old 22nd September 2006
mrdeezy's Avatar
mrdeezy mrdeezy is offline
Active Member
 
Join Date: Jul 2006                                                
Location: San Diego
My Saabs: 1999 9-5
Posts: 32
Default

Call me stupid but my throttle body blew up on a road trip.I had to go to an indy to get it replaced.I had a check engine light, limp home mode, and basically no idle.They switched the TB.And told me it was NON serviceable.I took home the old one and took it apart.There are potentiometers and sensers involved in that that cannot be replaced.So how can reprogramming overcome basic wear and tear on a vehicle?The 9-5 TB's basically last 80-100K but once the tps or other sensors get out of range,how can you just reprogram it?Is it to compensate for the failing electronics?
Reply With Quote Quick reply to this message
  #4  
Old 22nd September 2006
DriverEd DriverEd is offline
Senior Member
 
Join Date: Aug 2003                                                
Location: Toronto, Canada
My Saabs: 2005 9-3 ARC CV, 2000 9-5 SW 2.3lpt
Posts: 240
Default

aikman, the TB was rather an easy DIY - all you need is a basic set of sockets. My DI was changed almost 2 yrs ago, so I don't think it had any impact on my TB failure.

mrdeezy, I'm not sure on how all this re-programming of the TB is supposed to work. You're right: there's no software in the TB, just sensors. A guy named "cliche" responded to my other thread and said that Saab had sent a bulletin to dealers advising them to reprogram instead of replace. AFAIK, reprogramming is done via tech II to adjust the TB settings - which is basically, as you said, to compensate for the failing electronics!
Reply With Quote Quick reply to this message
  #5  
Old 23rd September 2006
aikman7981 aikman7981 is offline
Senior Member
 
Join Date: Sep 2006                                                
Location: hawaii
My Saabs: 2000 9-5 Aero sedan, 2.3T auto
Posts: 161
Default

So I should ready myself for a complete TB failure? My 2000 only has 46000 miles on it! how can the TB be bad so soon? Is there anything else I should ready myself for? Three trips to the shop in two weeks of ownership AND this car has been taken care of (has maint. records). A local indy has a TB from a 9-3 he can install for me, should I just do that while I'm in for my rear shocks to avoid getting towed?
Reply With Quote Quick reply to this message
  #6  
Old 23rd September 2006
Kermit's Avatar
Kermit Kermit is offline
Saabista
 
Join Date: Sep 2004                                                
Location: London UK
My Saabs: 04 9-5 Vector 2.2Tid
Posts: 11,017
Default

Aikman, are you having problems or are you looking to change the TB for no reason? Mines a 99 model with 111K miles original TB, i just give it a spray of carb cleaner every 3 months or so and alls well.
Reply With Quote Quick reply to this message
  #7  
Old 23rd September 2006
aikman7981 aikman7981 is offline
Senior Member
 
Join Date: Sep 2006                                                
Location: hawaii
My Saabs: 2000 9-5 Aero sedan, 2.3T auto
Posts: 161
Default

Not really no reason. Call it preemptive since I've had it reprogrammed after the first TB failure. I just don't want to get stranded by my very finnicky (thus far) Aero.
Reply With Quote Quick reply to this message
  #8  
Old 23rd September 2006
mrdeezy's Avatar
mrdeezy mrdeezy is offline
Active Member
 
Join Date: Jul 2006                                                
Location: San Diego
My Saabs: 1999 9-5
Posts: 32
Default

I don't think it will strand you my car was driveable when mine went out.But it would not idle well,I could drive it on the highway if i had too.You could reset limp home mode and it should run for a while,but not too well.As for mine about 2000 miles in i got a bad idle at stop lights which started becoming more common as time went on.I did the carb spray for a month it helped but it basiclly gets less ffective everytime you do it,tried new plugs then eventually pulled up to a stop light and the car almost died.and was idling at 400 rpm or so.Also on long trips,i drive 6-7 hours to my parents home.After about 4 hours the car would start stuttering at cruise.Which is terrifying when theres no cell phone service or gas station within 40 miles of each other on highway 5 in california.Got the tb fixed,the indy charged 350 for the part.I called the dealership they wanted 524.So it wasnt too bad,the car runs flawless now.I originally thought the throttle body might get worn down from the oil blow by of the turbo.But after i opened it up.It really is totally different creature than i expected.The electronics are not serviceable.So i guess its part of the joy of owning a saab.
Reply With Quote Quick reply to this message
  #9  
Old 23rd September 2006
Kermit's Avatar
Kermit Kermit is offline
Saabista
 
Join Date: Sep 2004                                                
Location: London UK
My Saabs: 04 9-5 Vector 2.2Tid
Posts: 11,017
Talking

Quote:
Originally Posted by aikman7981
Not really no reason. Call it preemptive since I've had it reprogrammed after the first TB failure. I just don't want to get stranded by my very finnicky (thus far) Aero.
Hey, if its working fine don't fix it. You never know when the 5.1ABS unit goes out and you need the money for that.
Reply With Quote Quick reply to this message
  #10  
Old 23rd September 2006
aikman7981 aikman7981 is offline
Senior Member
 
Join Date: Sep 2006                                                
Location: hawaii
My Saabs: 2000 9-5 Aero sedan, 2.3T auto
Posts: 161
Default

The 5.1 ABS? Oh goodie, tell me more. Will I ever have money I can use for things not associated with this car?
Reply With Quote Quick reply to this message
  #11  
Old 24th September 2006
Kermit's Avatar
Kermit Kermit is offline
Saabista
 
Join Date: Sep 2004                                                
Location: London UK
My Saabs: 04 9-5 Vector 2.2Tid
Posts: 11,017
Default

I'm joking with ya. Its not unusual for them to go though.
Reply With Quote Quick reply to this message
  #12  
Old 26th September 2006
gohunter gohunter is offline
Junior Member
 
Join Date: Sep 2006                                                
Location: Wirral, UK
My Saabs: none any more
Posts: 23
Default

Guys, having worked in computer automation systems some years ago, I can explain how you can "reprogram the throttle body" when there is no software in the TB itself. What you are actually doing is reprogramming the way that the TB is driven by the ECU. The TB responds to commands from the ECU driving the motor for the throttle and the ECU gets its feedback from the potentiometers etc in the TB. It is actually the ECU that is being programmed to work with the TB and not the TB that is being reprogrammed. Sensors in all sorts of systems go out of calibration over time, but all you do is run tests which measure the feedback and recalibrate them to compensate. In this case you measure the amount of fuel going in and the exhaust emissions coming out and the ECU gets programmed to the TB's sensors in their current state of calibration to give the optimum mixture.
Reply With Quote Quick reply to this message
  #13  
Old 26th September 2006
robw's Avatar
robw robw is offline
Saab Lunatic
 
Join Date: Sep 2004                                                
Location: Doylestown, PA USA
My Saabs: '03 9-5 Aero manual
Posts: 2,246
Default

Gordon,

Thanks for helping to clear up some of the "throttle body reprogramming" mystery.
Reply With Quote Quick reply to this message
  #14  
Old 26th September 2006
DriverEd DriverEd is offline
Senior Member
 
Join Date: Aug 2003                                                
Location: Toronto, Canada
My Saabs: 2005 9-3 ARC CV, 2000 9-5 SW 2.3lpt
Posts: 240
Default

thanks gohunter - but that raises another question: My mechanic had tried the re-programming route, but that was on the old, dying TB. Now that I've replaced the TB, does the ECU need to be re-programmed again?
Reply With Quote Quick reply to this message
  #15  
Old 26th September 2006
aikman7981 aikman7981 is offline
Senior Member
 
Join Date: Sep 2006                                                
Location: hawaii
My Saabs: 2000 9-5 Aero sedan, 2.3T auto
Posts: 161
Default

Well DriverEd my car is following yours verbatim. I'm surging again, not so bad yet but I expect it to get worse and then go into limp. Unreal, the reprogram only held for about 1 week. So if I do install the TB myself will I need my ECU reprogrammed?
Reply With Quote Quick reply to this message
  #16  
Old 26th September 2006
DriverEd DriverEd is offline
Senior Member
 
Join Date: Aug 2003                                                
Location: Toronto, Canada
My Saabs: 2005 9-3 ARC CV, 2000 9-5 SW 2.3lpt
Posts: 240
Default

Quote:
Originally Posted by aikman7981
Well DriverEd my car is following yours verbatim. I'm surging again, not so bad yet but I expect it to get worse and then go into limp. Unreal, the reprogram only held for about 1 week. So if I do install the TB myself will I need my ECU reprogrammed?
1 week is how long mine lasted too. I haven't reprogrammed the ECU yet (I changed the TB on Sep 16th) and the car's running fine but I did notice a very slight rough idle the other day. It was barely noticeable, but I am hypersensitive to this issue right now . I'm still trying to find out if a reprogram might be needed - it certainly would make sense, given the info that gohunter just posted.
Reply With Quote Quick reply to this message
  #17  
Old 27th September 2006
aikman7981 aikman7981 is offline
Senior Member
 
Join Date: Sep 2006                                                
Location: hawaii
My Saabs: 2000 9-5 Aero sedan, 2.3T auto
Posts: 161
Default

Thanks for all the info on this perplexing subject. Does anyone have ideas about perhaps cleaning the TB instead of replacing it? I don't want to waste time or money (although both are likely). I'm hoping to nip this before limp mode kicks in and strands me somewhere.
Reply With Quote Quick reply to this message
  #18  
Old 27th September 2006
gohunter gohunter is offline
Junior Member
 
Join Date: Sep 2006                                                
Location: Wirral, UK
My Saabs: none any more
Posts: 23
Default

Quote:
Originally Posted by DriverEd
thanks gohunter - but that raises another question: My mechanic had tried the re-programming route, but that was on the old, dying TB. Now that I've replaced the TB, does the ECU need to be re-programmed again?
Yes, if you have changed the throttle body you really should have it calibrated with the ECU. If you don't then you may find that the fuel consumption is not as good as it should be, or the performance, or the next time you go for an MOT test, or whatever the equivalent is in Canada, it may well fail due to the emissions being too high. I presume like us, you will have an annual test on all cars for safety, emissions, etc.
Reply With Quote Quick reply to this message
  #19  
Old 27th September 2006
DriverEd DriverEd is offline
Senior Member
 
Join Date: Aug 2003                                                
Location: Toronto, Canada
My Saabs: 2005 9-3 ARC CV, 2000 9-5 SW 2.3lpt
Posts: 240
Default

Quote:
Originally Posted by aikman7981
Thanks for all the info on this perplexing subject. Does anyone have ideas about perhaps cleaning the TB instead of replacing it? I don't want to waste time or money (although both are likely). I'm hoping to nip this before limp mode kicks in and strands me somewhere.
You can try cleaning the TB, but it sounds like the problem with yours is electrical, which can't be cleaned.

In any event, to clean the TB, get a can of carburator or TB cleaner and spray it into the TB with the engine running (the delivery pipe must be removed first). The car will stutter and stall and you'll see smoke coming out the back. You'll also get a check engine light which you can clear by disconnecting the battery for about 10 seconds. Make sure you read the instructions on the can in case I forgot something.

My TB was very clean (even cleaner than the one I replaced it with) - it was one of the electrical sensors that was shot - a client of mine (a mechanic) suggested it was a voltage sensor that was bad.

Quote:
Originally Posted by gohunter
Yes, if you have changed the throttle body you really should have it calibrated with the ECU. If you don't then you may find that the fuel consumption is not as good as it should be, or the performance, or the next time you go for an MOT test, or whatever the equivalent is in Canada, it may well fail due to the emissions being too high. I presume like us, you will have an annual test on all cars for safety, emissions, etc.
Thanks again, gohunter - I'll get it recalibrated. Although, my fuel comsumption has been better than ever .

In Ontario, we have a "DriveClean" program that requires an emissions test every two years, starting when the car is 5 yrs old. It used to start when the car was 3 years old, but they found that 99% of 3 yr old cars were passing the initial test. You guys have yearly testing??? Ouch. What a waste of time and money.
Reply With Quote Quick reply to this message
  #20  
Old 27th September 2006
aikman7981 aikman7981 is offline
Senior Member
 
Join Date: Sep 2006                                                
Location: hawaii
My Saabs: 2000 9-5 Aero sedan, 2.3T auto
Posts: 161
Default

Wow, all questions answered. So I guess I'm in the market for a new (or used) TB. The bad news is once I get that installed I have to go to the dealer and pay $115 to have it calibrated. Yech. Well, I can probably do this outside the dealer for around $500 total instead of the $700 they want. Thanks a lot to both DriverEd and GoHunter!
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Reply

Bookmarks

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the SaabCentral Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools
Display Modes

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 12:50 AM.



Powered by vBulletin® Copyright ©2000 - 2014, vBulletin Solutions, Inc.

top of page | sitemap | email us



copyright © 2003 - 2011 saabcentral.com, All rights reserved http://www.whiter.co.uk - valid xhtml - valid css
SaabCentral is an independently run website and is not affiliated in any way to Saab Automobile AB.


Garage Plus vBulletin Plugins by Drive Thru Online, Inc.