Cold start problem and then high iddle

[Trepifajxl]

Hello,

I have a problem with my 9-5 2.0LPT (year2000). It worked well, but suddenly the idle jump to 2000 rev/min. I adjust the throttle to closer position and idle was fine. Not for a long period.
Now, when I want to start cold engine I have to stay on throttle pedal and by that keep revs at 2000 for aprox. one minute.
Than it idle at 900 rev/min. When engine is warmed up, revs go to 1500, sometimes fall down to 1200. When I switch on A/C it falls down to 1000. In term of A/C, I cannot switch it on when engine is not warm, since engine turns off.
I recognized, turbo bypass vetil is bad cause lean mixture, but when I change the part (was broken) engine goes more smooth, but problems with starting and idle are the same.
Thank for any suggestions.

Ondrej.

P.S. Sorry for my english

[Kermit]

Ondrej, how did you "adjust throttle to closer position"?

[Trepifajxl]

Hello, very easy. There is a stop screw for pulley od throttle. Just to have the throttle more close.

[Kermit]

Reason i ask is the throttle body is fly by wire and idle adjustment should be done via Tech 2. I think you may be adjusting something else hence the crazy idling speeds.

[Trepifajxl]

I´m not sure we are on the same page I have Saab 9-5, 2.0LPT, year of production 2000. Mileage 192000km. There is normal cable wire.
edit: I´ve just recognized there should be battery 12V/70Ah/640A and currently there is 12V/44Ah/440A. Could this cause my problems? In the night I´ve recognized down of lights for a while and then back to normal (it repeats).

[MacNoob]

Is it possible that the euro 9-5 for 2000 was available without traction control and electronic throttle?

If this was a north american (NA) car I would say that you are in throttle body limphome mode. On a north american car there is a cable, but it is normally disconnected.

TB looks like this in NA:

http://photo.platonoff.com/Auto/2004...006g.Hoses.jpg

[gghh]

All petrol 9-5 have electronic throttle body - there is no manual adjustment. Idle speed is determined by the ecu.

Reset your limphome mode.

[Trepifajxl]

Hello, yes TB seem like the one from picture. And on the left down corner you can see cable to pulley. Maybe I´m wrong. Does it work like pulley is driven by cable+pedal and it gives impulses to the right side of TB (under black cover)? Then it is fly by wire and I´m sorry for bad stand.
What you you mean by home limp mode? Car is gogin well, just except this problem. Maybe consumption is more than I´ve expected...
It is for petrol and LPG as well. Issue doesn´t occur ased on fuel used, maybe better attitude when LPG.
Could lambda sensor do that? I have doubt it is bad (mileage and LPG).
What about battery? Is it possible it has an impact?
What I should do? Go to service? Or shall I do something at home?

Thanks a lot

[Trepifajxl]

Originally Posted by gghh

All petrol 9-5 have electronic throttle body - there is no manual adjustment. Idle speed is determined by the ecu.

Reset your limphome mode.

OK. How should I do it?

[gghh]

Return the limiter screw to the original adjustment and follow the instructions in the frequently asked questions to reset limphome.

[Trepifajxl]

Originally Posted by gghh

Return the limiter screw to the original adjustment and follow the instructions in the frequently asked questions to reset limphome.

do you have a link please?

[gghh]

http://www.saabcentral.com/forums/sh...ad.php?t=23073

[Trepifajxl]

Thank you very much. From video it is absolutely clear.
On the bottom under the wheel you can see bolt with locknut what I were talking about.
Is there any danger whe I do it? Some mentioned that: I do not recommed you to do this reset, because you LOOSE the DTC that triggerd the limphome. I´m not sure what he meant.

[gghh]

By disconnecting the battery you loose the error codes stored in the ecu but you need to reset them as limphome will be triggered again if there is a limphome code stored.

Its not dangerous. Try it, if its triggered again you need to do further research as most likely your TB is bad.

[Chris 9-5]

Originally Posted by gghh

most likely your TB is bad.

Agreed

[Trepifajxl]

OK, thanks a lot guys. I hope it´ll stay on its place...and TB is OK. Or does it mean TB is, let say 90% damaged?
i´ll let you know...

[Trepifajxl]

Hello guys,

I did the reset TB from limp mode. Engine start well, but has no reponse to pedal press. Is that what you mean? TB is defective?
I´m wondering how TB switch to limp mode...

[MacNoob]

Normally a bad throttle body will set a diagnostic trouble code (DTC) in the engine control unit (ECU) and ignite the check engine light (CEL).

There is not normally any mechanical connection between the throttle pedal and the throttle body (TB). It is operated electrically - there is a sensor at the throttle pedal that sends a signal to the ECU - the ECU then operates the throttle blade in the TB via a small electric motor in the TB.

When certain DTCs are set (CEL is on), the limp home solenoid on the TB will fire when the key is turned on (CLICKCLICKCLICKCLICKCLICK) - a pretty obvious noise. The solenoid trips the spring that locks the black drum to the throttle cable and allows the throttle pedal to control the TB directly. This is limp home mode (LHM).

To reset LHM, you cleared the DTCs (disconnect battery or pull ECU fuse or use an on board diagnostics (OBD) reader to reset) then reset the spring as per the frequently asked questions (FAQ) document.

You mention LPG - is it possible part of the conversion involved making the TB operate manually? We don't see LPG cars in North America.

[Trepifajxl]

OK thanks for explanation.
So you mean, anything, for example lambda sensor could cause this Limp Mode?
I did it exactly as you descrice. disconnect battery, set the spring back and try to start. It starts, but when I move throttle pedal, engine doesn´t react.
Does it mean TB is defective? You know I don´t want to buy new one and recognize it was good and something else is wrong.
In term of LPG. It is sofosticated system cooperating with almost all engine senzors, so I would say, no it shouldn´t be caused by LPG.
On diagnostic, it says catalysator problem. But I wasn not there during this measurement, so I´m not sure. Do you thing some problem, for example lambda failure, can cause TB doesn´t work even when is reset? It didn´t fall into limp mode againg. Just didn´t react for anything.

[MacNoob]

If you are not getting a CEL, but TB is not moving when you operate the throttle pedal, the problem could be at the pedal - I don't know where the pedal position sensor is though :-( but it sounds like maybe the pedal position sensor is unhappy - not detecting any movement of the pedal.

Normally only a TB problem can set a code that will cause LHM. Other codes (for example your oxygen sensor) will set a DTC and ignite the CEL but will not cause TB LHM.