NEED HELP!!!!! 2007 Saab 9-3 2.0t

[sorin564]

I bought the car 9 months ago and ever since I've been experiencing this problem.
In the morning, at a cold start, the car idles rough, stutters severly,  until the car heats up a bit. Feels like it is a misfire and was diagnosed by a Mechanic as a misfire. Car also runs weak until the car's temp gets to its proper temperature. After that, car runs better until I get to a stop light. At a light, the car idle is ruff, not as rough as a cold start but you can feel the engine idle feel shaky a bit. Again, at a light or just at a complete stop, the engine runs slightly rough and my lights also flicker, non HID. If im at a stop at night and i put my window down, the moment i press the button, the lights dim. Lights stay normal when i accelerate. I've changed throttle body, spark plugs and ignition coils and problem still exists. I've used multiple gas cleaners and have been using shell v-power since car was purchased. vacuum leaks were checked also and no problem there. I also had a compression check on the cylinders, injectors were checked, etc.
One thing I also tried was removing the plug on the MAF sensor to see if it would make a diffence in idle but removing it made no difference to the way the car ran at idle. I have also been experiencing a lack Of horsepower. It just seems to have lost some when press on the gas, almost like its not receiving enough air compression from the turbo or maybe not receiving enough gas? Hard to explain. I had the voltage checked to my battery when the car was on and the voltage came out normal. Could a bad alternator still show the right voltage when tested? Any ideas?
I've taken the car to a saab mechanic, someone who has worked only on saabs for 20+ years. He couldnt find anything wrong. All his computer read was a misfire at startup but coulnt diagnose the problem. (his credibility was in question though because he was not the head mechanic in his shop. Head mechanic was on vacation). Can someone please help me?? Its been 9 months and same problem. Problem has not gotten worse. It stayed the same.
I bought a SAAB because of the praise it got from everyone i know that has one. Now, I'm starting to hate it! I work 11 hours a day. Mornings, car runs like crap until it heats up. If I leave it off for more than 3 hours, the car does it again. The car starts off rough on cold starts only when the cars has been off for more than 3 hours. When i get out of work, all i want to do is get home but i have to wait until the car warms up a bit, and then start driving it.

Specs: 2007 saab 9-3 2.0t automatic 55,000 miles.
I also took it the dealer but the Warranty is void. no clue why. Some please help me!!!! I want to fall in love with my saab!

[Max Headroom]

Hello Sorin, and welcome to the forum. 

Sorry to hear you are having a whole bunch of problems here, but I reckon you will get to the bottom of it eventually.
I'm not well qualified to give you much help here Sorin, but Im sure someone will be along soon.

1) Until you said that the alternator was kicking out enough power I was thinking along that line, to be honest.
2) Have you had the codes read on a Tech II? If not I would advise getting that done as soon as possible.
3) Also, check all the earthing and bonding harnesses are in good condition and not broken or corroded at their attachment points - particularly the one between the engine block and the body/chassis.

Hopefully someone will be along soon that can point you to some more possibilities.

PS Your name? Any connections with Romania?

[Saabman]

I too would be checking all the earth bonding straps, I'd also be trying a known good battery just to rule that out.

[Audax]

All his computer read was a misfire at startup but coulnt diagnose the problem. (his credibility was in question though because he was not the head mechanic in his shop. Head mechanic was on vacation).

Right, if there is a fault being logged then it will give the clues to find the problem. Do you know what that fault code was? The only real way to get this sorted is to find out what that fault code is and go from there, it could be a faulty ignition coil or it could be a faulty temp sensor or something else. I'd take it back to that place when the head mechanic is available, it sounds like the person you spoke to wasn't much more than a fitter.

It sounds like that the engine management is aware of a problem and is using a default/fall back value which makes some assumptions but when the engine is hot the fall back value is correct and the car runs OK (but probably not optimally). Does the check engine light come on and go off when you turn the ignition on? and is the check engine light coming on when you're driving?

[sorin564]

Hello Sorin, and welcome to the forum. 

Sorry to hear you are having a whole bunch of problems here, but I reckon you will get to the bottom of it eventually.
I'm not well qualified to give you much help here Sorin, but Im sure someone will be along soon.

1) Until you said that the alternator was kicking out enough power I was thinking along that line, to be honest.
2) Have you had the codes read on a Tech II? If not I would advise getting that done as soon as possible.
3) Also, check all the earthing and bonding harnesses are in good condition and not broken or corroded at their attachment points - particularly the one between the engine block and the body/chassis.

Hopefully someone will be along soon that can point you to some more possibilities.

PS Your name? Any connections with Romania?

Codes came out to be either cylinder 3 misfire or cylinder 4 misfire. I had them replaced and the same thing is occurring. I had compression checks done on the cylinders also to make sure the compression is not low, so a bad valve or bad intake valve are out of the question. I will check the attachment points and see what i got there.
And yes, I was born in Romania

[Audax]

OK, I wonder if you have an air leak on the intake manifold around cylinder 3 and 4, something that gets sealed up when the car is warm? Have you tried spraying some air intake cleaner over the engine bay when it's running like this to see if it changes engine note which is a sure sign of a leak?

[jmblack]

Had a similar experience from air leak on servo assist although this showed misfire on different cylinders at different times.

[Guyver1]

Stop using V power fuel for a start

It should say in your fuel flap. Ron 95 only

If your engine doesn't like the 98ron fuel like a lot of engines don't, that can cause a misfire

Mine was running rough on V power, now I put asda bog standard 95ron unleaded and the idle is much smoother

Give it at least 2 tanks of normal fuel to get a good idea of how it runs

[Audax]

If your engine doesn't like the 98ron fuel like a lot of engines don't, that can cause a misfire

  All 9-3 should run fine and better on 98 ron fuel. If yours wasn't then there was some other problem. The 95 ron only sticker means minimum of 95 ron, anyhow I can't see anywhere the poster said that they were running on v-power?

[sorin564]

OK, I wonder if you have an air leak on the intake manifold around cylinder 3 and 4, something that gets sealed up when the car is warm? Have you tried spraying some air intake cleaner over the engine bay when it's running like this to see if it changes engine note which is a sure sign of a leak?

All leaks were checked. Mechanic sprayed intake cleaner all over the engine and there was no change in RPM. Well, he said he checked but i should just buy a can and try it on my own also for verification.

Guyver1
As far as gas goes, my manual says to use premium gas only, so i use premium gas only, mainly v-power. Gas is definitely not the problem.

[aerojon]

check the vacuum pipes & joints around the dipstick ,under the black cover tend to crack there..

[MartinMc711]

I had misfire on 3 and 4 codes from my GM900 93 a while back, also stuttering engine when cold. Took some digging but it turned out to be the hose out the rear of the turbo, whatever that is.

Don't know if the last 93 would exhibit similar issues though...

[sorin564]

I will check that out this weekend. I've been working like a mad man the past 2 weeks and havent had time. If all fails, anyone know a good saab mechanic (other than the dealer) in Michigan that might be able to diagnose my problem? Appreciate it!