Poor acceleration/stumbling 1997, 850, T-5

Four volvos · Post by **Four volvos** » 30 Jul 2007, 11:31

Runs like a champ when it is cold!! Under load, after the engine is fully warmed up, 15+ miles on freeway, the engine stumbles and misses upon acceleration. The codes set are P0302 and P0202. I have been working on this for a while. The P0202 code is new as of this weekend, before was only P0302. I have been advised by indy Volvo guy to do all below. Other advice has been to fully warm-up the car and then pull the connector from each sensor while running and put them back on. The sensor that does not change how the car runs is the suspect one. Have not tried this yet. The following have been replaced:

Plugs: used Bosch FR7DC
Wires: Bougicord from IPD
Cap and Rotor: Bosch
Ran 1 bottle each Lucas injector cleaner and Redline cleaner through for 200+ miles. Change oil and filter to Mobil clean 5000 about 400+ miles ago.

Next step is to check compression in cyl #2, will do tonight.

Any other suggestions??? I am getting worn out by this one.

Thanks.

Klausc · Post by **Klausc** » 30 Jul 2007, 11:49

Sometime it is just the injector electric plug gets fouled up and needs a little cleaning. Also check the wires for chafing. The plastic shielding on the injector wires leaves a lot to be desired,
If the injector is truly dirty, injector cleaner in a bottle will not work. It is #2 injector.

Klaus