[hardi]

i just got a 3.2l 900s with 128,000 miles on it that wont idle and would die out if it dropped below about 1200-1300 rpm. i ran a bottle of seafoam thru and the problem changed from dieing out while driving to on the rare occation idleing perfectly. but at the moment, after starting the car it will pretty much die right away unless you gas it so that it revs above about 1000-1100 rpm. this is my first saab so im not sure, but what i thought could be the problem is that the plastic box that connects the intake hose to the throttle body does not have a air tight seal so that confuses the computer(on my car the plastic box just pulgs straight into the throttle body, there are two screw holes at the top of the throttle body that are not used, am i missing a piece that should be sealing the two together?) i attepmted to rig something to seal this and when i get a good seal the car will generally idle but rough and with fluctuations ranging from slight chuging to random high rev spikes. reving the gas generally causes it to die out.

possible Vacuum Leak?- there is a small rubber hose that comes out of the throttle body, the end of it is not plugged into anything, it has a small plastic piece in it but it doesnt seem to fit into anything. coming out of the head is a plastic piece that splits into a Y and has a larger rubber hose on the left and a small hole on the right that i think it should connect to but the pieces dont fit into eachother should i superglue it?(i cant find a picture for reference that shows this hose in the haynes manual)

i read the Guide to curing variable and high idleing as well as seached the posts and but im unfamiliar with all these sensors and its tough trying working on it myself and not being able to check the components with the car idleing because it wont stay running.

the throttle body itself is fairly clean and i cleaned out some buildup out of the hoses coming out from it . im not sure how to check if the o2 sensor needs replaced

(also int the middle of replacing my radiator hose and auxiliary belt the hood latch stopped popping the hood:x anyone know how i can get the hood poped now? )

any help is much appreciated
thanks

 

[escalator guru]

Hi Hardi and welcome to SC. Unless your car is a '94 convertible, you might get some better answers if your thread gets moved to the NG900 section, but I'll see what I can do--

First you're going to want to fish out the cable that connects to the hood lever inside the car. Usually if it slips off it doesn't go very far. Grasp it with some pliers, slide it back over the notch, and you should be in business.

Now as for what's going on under the hood... I would check the oil dipstick cap. This is usually the only advice I ever give here. Saabs are peculiar in that the dipstick / filler tube is part of the vaccuum system and the engine will not maintain a proper idle without it properly sealed. The symptoms of this being unsealed mimick very serious vaccuum leaks, so try that first.

As for your loose hoses, I've got no idea, sorry Best of luck

 

[hardi]

coincodentally right after making my post i came across this 900 FAQ where it described the poor idle after an oil change: http://www.thesaabsite.com/900old/900&79to94faqs.htm#Poor%20idling%20after%20an%20oil%20change!

it sounds alot like my cars problem but from what i can tell the cap is screwed on. the cap may however not be sealing very well, when i compress the cap(if as to turn to remove) when its on one side seems to go down lower then the other for whaever reason.

these are my observations regarding the dip stick cap, tho puzzling to me. first i removed the cap completely and started my car, and it idled(most recently the car has the tendency to die rather than idle so my initial reaction was that taking the cap off caused it to idle [the manner in which the car idles or doesnt seems to change and could be that i just got back from a short drive to test my radiator hose] ) but then upon starting the car with the cap on the car ALSO idled the same as with out it.

all in all i am still very confused but tommorw i will attemt to seal the dipstick tube to see if possibly the cap is faulty. every time i think i know what could be the problem trouble shooting that area just leaves me more confused:suprised;! could there be another part of the "crankcase ventilation" or whatever that could be leaking because that sounded alot like my problem

 

[JMarkert]

Welcome. I suppose the oil cap could cause some trouble, but I think you're really on to something with the plastic box connecting to the throttle body.

This site http://pages.infinit.net/mlbriand/saab/iac/page1.html

has some nice pictures of the plenum and its attachment. The box is sometimes called a "plenum" or "silencer". It is held to the throttle body with a big wire clip (this often flies off). If you don't have a clip, this is probably your problem. You might shine a flashlight around the back of your engine to try to find it if yours is missing. Also, there are two O rings that seal the plenum to the throttle body. You can coat these with grease, vaseline etc. to make a better seal.

And yes, it does sound like the small hose needs to attach to the "Y", it must have snapped off. You can get one of these cheap at www.thesaabsite.com or www.eeuroparts.com. Superglue might work in the meantime, but I would think it's hard to glue it and keep the hole open.

 

[hardi]

i dont have any O rings connecting the "plenum" to the throttle body its straight plastic to metal. can i find replacements anywhere?

 

[JMarkert]

Huh!?! Well that's probably a big part of the problem. You might check www.eeuroparts.com or www.thesaabsite.com, but I think your best bet might be to take the plenum to a car-parts store and experiment. Or mabe a junkyard if there is such a thing in Hawaii (what a waste of real estate!)

But at least your idle problem is explained.

 

[hardi]

i further traced the 2 small vacuum lines that come from the bottom of the throttle body and found them BOTH to be disconnected and i think they are the rest of my problem. the line on the left is a line thats was not plugged into anything and i have not figured out where that goes yet. the one on the right goes up to a sensor thats mounted on the lip above the firewall to the right of the engine a bit where it meets a blue colored sensor as well as splits out into a long vaccum line that runs to the front of the car near the radiator but is not connected to anything. it seems to be what is described here in the FAQ under "why my car stalls when i let off the gas", as the line that goes to a "charcol canister" but i have not located where this is or what that line should plug into yet either. also all those vacuum lines are decintegrating and will need to be replaced. if anyone knows where these vacuum lines should go or where i can find a diagram(havent found any good picture of this in the haynes maual) or if someone with a similar car woulndt mind checking there lines next time theyre under the hood it would be much appreciated
thanks for the help

also, could a overly high level of oil affect anyting? i juust noticed theres too much in there

 

[papaquebec]

How different is the V6 system? We pick our '94 V6 up Friday afternoon from the barge, so I could bring it over for you to study if it is the same set-up.

Pat

 

[PMI]

There is too much here to sort at the same time. Make sure people know what version of the car you have... (2.3 liter 900S non-turbo?)

If one of the PCV (positive crank case ventillation) system connections is missing, there would be a vacuum leak. Same if any other tb connections are missing.

The vacuum lines are not well described in the Haynes manual. On the 2.3L they are not the same as on the turbo engine. Until you get them repaired/connected, hard to say what else might be going on.

The non-turbo engine has the SAI (secondary air injection) system, which includes a couple valves and an air pump not found on the turbo. The long vacuum hose going to the front of the car may be a part of that.

The hose that goes to the charcoal canister is thicker than the vacuum lines. On the turbo, it connects to the throttle body at an angle toward the passenger side of the car, then goes to a valve, and from there to the charcoal canister. The charcoal canister is not in the engine compartment but either in the wheel well under the fender, or back of the car.

I would not worry about the dipstick tube and oil filler cap, unless they are obviously damaged or broken.

 

[Slaab4life]

The non-turbo engine has the SAI (secondary air injection) system, which includes a couple valves and an air pump not found on the turbo. The long vacuum hose going to the front of the car may be a part of that.

My non-turbo doesn't have the SAI system. My whole ownership of the car, I've been purplexed by that.


Being able to depress the oil dipstick is normal. Sounds like you have some more serious problems besides that anyways, but easy enough to get straightened out.

Definitely take the plenum to a hardware/auto store and size some O-rings for it. Normally their are two O-rings on the plenum, a large one and a smaller one. You will see 'wedges' on the portion of the plenum that connects to the throttle body that will hold the O-rings in place. Do you have the clip on the plenum that holds it to the throttle body? Oh, and those two screw holes you were asking about on the throttle body, those are for the turbo models.

As for the vacuum line routing, if their is still doubt this afternoon, and its stopped raining here, I'll go out and take some pictures for you.

After all the lines are sorted and reconnected, you will probably want to clean the AIC valve.

 

[PMI]

My non-turbo doesn't have the SAI system. My whole ownership of the car, I've been purplexed by that.

Consider yourself lucky. According to the Haynes manual, it was "fitted only on US and Swedish spec. 2.3L models".

 

[hardi]

thanks yes i have a 2.3 non-turbo. and i guess i forgot to mention that i did fit some rubber around where the O rings were and did find the clip so there seems to be a good seal there now where there wasnt before, as well as clean the AIC valve and check and clean all the larger hoses connecting to the throttle body. i cleaned any carbon buildup around the throttlebody and on the butterfly valve edges as well. the oil cap and dip stick seal fine so i ruled that out. im running some seafoam thru the gas to try and clean out the injectors. ive done done everthing else i can think of or read to do unless i need a new o2 sensor. the last thing i need to sort out are where these 2 small vacuum hoses should go to i hope. they are definately a big part of the leak.

 

[earthworm]

This situation is a problem, I guess you bought this car used, and I think it may have been "tampered with" by the PO.. He may have removed the secondary air system, but did not account for the vacuum lines..

Do you have a dealer on the island you can trust ??

I suspect there may be some other parts missing..
And the Haynes manual is of little help, the $20 to $30 parts books helps some as does the owners manual.
On this site we have some excellent photos of all the engines(even the Diesel, I think)...

 

[PMI]

A bad O2 sensor should give you a check-engine light, a vacuum leak will not. To be honest, a small vacuum leak should not make the car stall, even if it needs to be fixed.

Along with the injector cleaner I would replace the plugs if I did not know how old they were, and have the oil and air and oil filters changed... not a big expense compared to an O2 sensor, and you will know you have the correct amount of oil.

The crankshaft position sensing and knock sensing works differently on a non-turbo, either one of those could make the car not start or stall if bad.

Keep an eye on the engine temp gauge, it should go up to 9 o'clock position within 5 minutes of starting the car, and stay there. If the vacuum lines were neglected, good chance the coolant thermostat was never replaced.

 

[Slaab4life]

Consider yourself lucky. According to the Haynes manual, it was "fitted only on US and Swedish spec. 2.3L models".

Hmmmmm, I've got the US version. Nothing in any document says otherwise. What and where does the system connect to? I might have to do some investigating.

 

[PMI]

Hmmmmm, I've got the US version. Nothing in any document says otherwise. What and where does the system connect to? I might have to do some investigating.

Hope it never fails. The pump lists for over $300, the air filter alone for $60. The control valve mounts on the firewall on the driver side, behind the strut tower brace. Three more valves, a bunch of hoses and sensors, I bet over thirty parts total. The evap system is simple by comparison.