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Discussion Starter · #1 ·
1999 9-3 sqr tuned gt28rs volvo greens 3.8 bar fpr. Trionic 5.
Guys-hope you can help-I'm running out of ideas...
I have had an ittermitent problem for a while now.The car will be o.k. for a few days and then run like crap.It misses, has a very rough idle, and now has heavy black smoke at idle. I also am picking up random very high temps on my egt gauge (~1100 C) and my gas mileage also sucks.Seems to happen more when it's all warmed up and has been driven for a while. Sometimes idle also sticks up high.CEL actually starts flashing when it's running really bad.Went to Advance Auto parts and read the codes,here's what i got:
P1171 Manufacturer Control Fuel Air Metering
P0171 System Too Lean
P0300 Random/Multiple Cylinder Misfire Detected
P0106 Map/Baro CKT Range/Perf
P0130 O2 Sensor Bank 1 Sensor 1
Also had a code for crank position sensor one time I read the codes.Been there like 5 times already!

I just changed the front o2 sensor with a brand new one and checked all the wiring-it's fine.
I just swapped the Map sensor and DI from my 97 9000 aero that had been running fine into the 9-3.Both cars still run the same after swapped parts. Same exact parts and p/n's.
No bpc-running mbc.
Fuel pump replaced a little while ago with 044 Bosch Motorsport and I can hear it running steady while idle is all over the place so i think that should be o.k. too.
Cleaned out the Evap valve and checked to make sure it had equal length ticks coming out of it (stable pulse width). Cleaned out the IAC valve a little bit but didn't go crazy on it. Checked all vacuum lines-fine.
Any ideas? I don't know what else could possibly be causing this but I'm starting to think the ECU is at fault. The ecu has been in for a long time and the problems are recent but I guess in rare cases it could go bad.
Any other ideas? (FPR,injectors,Coolant or air temp sensor?) Wish i had some kind of datalogging for the values form all the sensors.
I have emissions due very soon and am trying to get this straightened out before then. Any help you guys can give would be great. Thanks a bunch.
 

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Idle sticking high, could be the throttle position sensor (not a common fault, but possible). Inside of the throttle body could need cleaning (similar symptom).

Vacuum leak, from one of the vac lines, or the evap canister purge valve, or evap lines could make the engine run rough at idle, or high idle (too much air going in when or vacuum, too little on boost). That would also account for the P0106, MAP sensor, an mpg, because the FPR is not regulating to the manifold pressure. Teh vacuum line from the TB to the FPR is hard to inspect, because it runs under a bunch of other stuff, and you can hardly even see the FPR.

The crank position sensor can be checked for nominal resistance with engine off and sensor unplugged, but if it is failing with a running engine only, it may be hard to test.

Coolant and air temp sensors can be checked more easily, measuring resistance first with engine cold, then hot.

Edit:

CPS: 540 ohms with a cold engine, +/- 10%
Temp sensors: over 2000 Ohms with a cold engine, around 200 Ohms hot.
 

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yes - follow the diagnostic tree that goes with those codes (that's the hard part - reading codes is easy!).

The codes don't tell you what's wrong - they just tell you what's affected.
 

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Discussion Starter · #5 ·
O.k. well I replaced my fpr with a known good one and put a new set of plugs in.They were very black from running rich at idle.Still no change in performance of the engine.It's stumbling,misfiring,running rich at idle, then it's giving me a lean condition code.Not sure what to look at next.Someone on another board suggested vacuum leaks.

Any more ideas?
 

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The engine is using too much fuel, the MPG must be horrible.
And, only R. Clemens could throw the codes faster with this condition...
I think that a correct interpretation of the codes will be the solution...
Has the temperature sensor been checked ? This will allow more fuel during the cold times( the first 5 minutes when the engine is trying to attain operating temperature)....
So, is there any difference between the cold and warm engine run qualities ??

The tale of the plugs : I do not think all four injectors would fail simultaneously or to the same degree, so is there a difference in how each plug appears after, say, 1,000 miles..
Not only that ( the plugs being black with soot); the oxygen sensor may not look any better - this can be cleaned, I believe..
 

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Discussion Starter · #7 ·
Update...
I am not losing any oil and virtually no coolant (could have gone down before by working out air bubbles after I had the system open). The car is running rich at idle. I can see black smoke (and smell it) coming out the tailpipe at idle.There is no white or blue smoke which would be indicative of oil or water burning.
I swapped in a known good fpr,map sensor, and DI cassette form my 97 9000 aero and also put in a new set of plugs-still runs the same or close to the same.
I also did the following today:
Cleaned and reconnected a bunch of grounds.
Checked all vacuum lines
Vacuum when warm at idle is about 550 mm HG (not sure of conversion)
Removed IAC valve,cleaned,reinstalled.
I also performed the resistance checks on the IAC valve, TPS,CPS, and IAT sensors and all checked out o.k.
Cleaned throttle body.
I think that's it for now.
Any ideas?
Mike Saunders suggested the injectors could be bad but they all have the same black appearance from rich running.I don't think they would all go bad all at once unless something really bad happened.
Question:If front 02 sensor was not working, would it make it run really rich at idle?Still have to check this.
Thanks for everybody's help.
 
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