Engine revs and stalls

[Natoqc]

Hello,

Have owned the same car for almost 20 years (9-5 MY1998) , bought second hand when almost new.

Has been serviced and repaired regularly with good oil change intervals etc...

Last problem ( last week) was oil pressure , changed the oil pump, took it for a 30km drive and no problem (oil light would go on at low revs when engine was hot) .

The following day while on the motorway (freeway for those on the other side of the pond) the car rev'ed on its own and stalled . I managed to coast onto the hard shoulder. When I turn the key the car will start, rev up to about 3000 rpm then idle for a second or two and stall. I had the car towed home as there is no garage around willing to look at it (I live in France, month of July when everybody goes away on holiday and all shops/garages close).

There is a check engine light but I cannot read the code. I bought an OBDII reader but it would seem the 1998 9-5 is not OBDII compatible and I do not have access to a Tech2 (but am still looking for one).

When I turn the key, before cranking, I hear a "tic - tic" sound (a bit like the sound of sparking) that seems to be coming from the throttle body. I don't know if it's usual and never noticed it. Obviously I checked the wiring and there does not seem to be anything untoward.

I checked for vacuum leaks. I found a couple which I have repaired but to no avail.

I changed my CPS about 3 years ago so I do not think it's that.

Serpentine belt is OK, I checked it while changing the oil pump.

I've done a rather extensive internet search but have not found any posts related to this exact problem.

Also how do I know if the car has gone into Limp Home mode? Would such symptoms kick-in the Limp Home?

Is it possible that it is a stuck throttle body that needs cleaning?

Any ideas would be helpful.

Many thanks for your responses

[TomTurbo]

Hey

How old is the ignition cassette? Do you have the possibility to borrow one? Just to try it out.
With the throttle valve the cable insulation is often broken inside.
If you open the black cover on the side you can see the cables.
If the cable isolation are broken, they have to be insulated or used throttle valve has to be installed.

[mvanastacio]

Hi! Did you solved the problem?
My 9-3 is doing almost the same... Yesterday it revs to 4000rpm than idle, then revs again but it doesn't stall.

Also, before this, at reward or downshifting it wents on limp.
A DIC is ordered and i'm waiting for it to instalo and change spark plugs.

But if you have solved the problem, i can check it more easily.

Thanks

[Digger]

Hi! Did you solved the problem?
My 9-3 is doing almost the same... Yesterday it revs to 4000rpm than idle, then revs again but it doesn't stall.

Also, before this, at reward or downshifting it wents on limp.
A DIC is ordered and i'm waiting for it to instalo and change spark plugs.

But if you have solved the problem, i can check it more easily.

Thanks

Cleaning the throttle body solves many a problem, but I can only guess at your problem being the idle air controller inside the throttle body, or the throttle body itself being the problem as you posted your 9-3 in the 9-5 section without listing the year of your car.

[mvanastacio]

Yeah, sorry...
Didn't notice that was a 9-5 section (noob here).

Indeed i have a 9-3 T7.
I'll give it a try on cleaning the throttle body.

Thanks