saab 900s contanst chugging

[Saab 257000]

I have a saab 900 S no turbo 257,000 miles+. i have experienced trouble while driving in all gears. the car seems to be "chugging" and occasionally black smoke comes out of the muffler. it starts up fine but when i begin to drive it jerks. when i come to a stop i have the clutch in and sit on the brake and the RPM will begin to rev up. and just recently the steering became hard to turn because engine was running so poorly. i replaced the sparkplugs, rotar , and cap. but still runs terrible. is it some type of sensor... Whats my problem??????

[jetman]

Black smoke to me is either AMM or other air problem

[Jim Mesthene]

Barring the truly unusual (ie: fuel pressure regulator diaphragm), only 3 things can make an LH system run very rich: AMM or vacuum leak (as mentioned) or NTC sensor circuit.

[CBC]

Just resolved a very similar problem with my 92 900 NA. First I replaced the AIC which helped only slightly. Then I replaced the AMM and this solved the problem immediately. Both replacement parts were used, since they are terribly expensive new.


Good luck tracking down the problem.

[jetman]

I've got a constant chugging problem and the beginnings of a little beer gut to show it

[Saab 257000]

hey thanks alot guys. im fairly new to the saab brand of cars, i bought it from my brother in law, and i dont what the AMM is. can you explain it in detail, as in where its located?? thanks again for your replies.

[jetman]

Inline between the air filter and the throttle body. Its a squarish black box about 3" x 6'. Its the Air Mass Meter. It measure air flow. It would appear that yours is good and wonked and is sending an erroneous signal to the fuel sender to send more fuel. Thus your rich mixture problem.

[CBC]

SAAB 257000 - Since both our Saab's are the same year and are non turbos, they should have the same Bosch Air Mass Meter. I double checked the part # on mine and it is - 0 280 212 019. I'm still rather new to Saab's myself, so I'm not sure AMM's with different part numbers are interchangeable. From what I can tell, they are not interchangeable, but someone else with more expertise will be better able to speak to this.

I bought my used replacement AMM off eBay for under $50.

[Saab 257000]

hey im back. i replaced the AMM like you guys said might be the problem but it didnt work. it is still running very poorly. now it seems to be severly misfiring.
any other ideas of what it might be?

[Saab 257000]

Hey im back and i though i would write what i found out about my car problem. i had 2 opinions that it was the crank shaft sensor so i got it replaced and now it runs great. just like it used to. the guy said that the sensor makes the car try to keep starting while your driving thats why it pulls so roughly. it wasnt cheap..$300 for the part and $700 total after installation but i couldnt live without my saab so i did it. i just thought i would let you all know the problem since i had been hearing from some others that they have the same problem. thanks for all your help!!

[Sha_kri]

Originally Posted by Saab 257000

Hey im back and i though i would write what i found out about my car problem. i had 2 opinions that it was the crank shaft sensor so i got it replaced and now it runs great. just like it used to. the guy said that the sensor makes the car try to keep starting while your driving thats why it pulls so roughly. it wasnt cheap..$300 for the part and $700 total after installation but i couldnt live without my saab so i did it. i just thought i would let you all know the problem since i had been hearing from some others that they have the same problem. thanks for all your help!!

I have a similiar problem. Do you know what part you replaced specifically, including the part #? Was it the "Crank Position Sensor?"

I must say that for every $10 spent on maintance on my Saab, $9 of it goes to trying to figure out what the probelm is.

[TheRedBaron]

Your car is an NG900, next time you'll get better responses if you use that forum (this is for "classic" 900s - pre '93/'94 vert).

Either way, yes, it's called the crankshaft position sensor. For your year it appears the "s" can have 1 of 3 engines. From what I understand this is a somewhat common failure on NG900 I4's.

2.3l 's' (what you probably have?) - http://www.eeuroparts.com/productdet...ts=1&code=4688

If you have the V6 - http://www.eeuroparts.com/productdet...ts=1&code=8384

Either way I might pop the question on the NG900 forum to see what they say, they might have other things to check before you splurge on parts...