Dear All,

I have a 94 960. a few days ago the car started to idle rough - Literally shake- i dont know is wrong since it started all of a sudden. I took it to a mechanic who said that i needed an engine tune up and possibly replace one of my ignition coils. however all six coils are working fine, so is the fuel injector and i did do a tune up as well. the car still idle roughs.

the mechanic has now told me that there seems to me some kinda electrical fault where only one pistion is working, he said my computer could have gone bad or some kinda wiring.

Can anyone please share there thought on this, i already spent 300$ and the problem is still there.

I live in southern NH so there not many reliable mechanics and the volvo dealers charge a fortune just to look at the car.

thank you

 

Has the car set any fault codes? You can read these using the diagnostic unit in front of the left strut tower.

 

Not that i am aware of. The mechanic ran the codes and told me that the car needed a tune up. i am guessing he diganosed the problem wrong.

i think it could be the intake gasket and fuel injector rings, based on the experinces of some other membes on this forum howeve ri am still open to sugesstions

 

If the mechanic checked the fault codes they would not simply say the car needed a tune-up. The codes are more specific than that. If the ECU, the 'computer', is faulty it would give outa code to that effect. If only one piston is working the engine would not run at all.

I suggest that you read the codes yourself and post the results for more help.

As stated in my first post the diagnostic box is mounted in front of the left strut tower. It is a small plastic box with a LED, a push button and a test lead. Switch off the ignition, open the lid on the box and plug the test lead into socket #2. Turn on the ignition and press the button once for between 1 and 3 seconds. Have pen and paper handy to note any codes.

The codes are seen as flashes on the LED. All codes are in groups of 3 flashes and the unit can store up to 18 codes. The codes are displayed like this ** - 3second interval - * - 3 second interval - ***. That would represent a code of 2-1-3.

The code 1-1-1 means no faults have been stored. If a code is displayed press the button again to see if any others are stored. Repeat untilthe first code is received again.Nofurther codes are in the memory.

It sounds complicated but is really easy. If you mess up you will do no damage, it just means you have to start again. The codes will still be there until you deliberately erase them.

Try it and post any codes you get.

To clear the codes from the memory display them as above. Press the test button for more than 5 seconds and release. The LED should light after 3 seconds. Press the button again for more than 5 seconds and release the button. The LED should be out. Now try to read the fault codes as detailed above. You should get 1-1-1.

 

thank you so you so much for your help. i let you know what comes.

thanks once again

 

I'm having the same problem, mine is not all the time, i could drive for an hour OK and then for a few seconds the engine shakes and then back to normal, it runs the worst after a gas tank fillup, i've replaced the oxygen sensors, the air mass sensor and power pack modules so far.
1996 964 178K miles