XC70 rough idle and poor throttle control Topic is solved

[bradm612]

the code is indicating the ecm isn't recieving throttle information.
I wonder if a throttle sweep test can be performed in vida whilst the engine is running.

You could try a drag test on the throttle plug contacts, or just cut it off and install a new plug.
Its a lot cheaper than a new thottle body.

Did a drag test, pins feel tight. Hopefully a shop can provide more insight with VIDA

[chrism]

“… What were your symptoms that led to you replacing the throttle body? Similar to what I'm seeing? Or did the throttle body not respond at all…”

It would be running fine then suddenly we would get the “Reduced Performance” message and lose almost all throttle response. The car would hardly get out of its own way. Scary when driving at night on a busy freeway. Shutting the engine off and restarting would restore performance. My local Indy Volvo pro said he had never seen a Bosch unit go bad, but I didn’t listen to him and went a bought a new one. I now believe I have a good used one sitting on the shelf.

[bradm612]

“… What were your symptoms that led to you replacing the throttle body? Similar to what I'm seeing? Or did the throttle body not respond at all…”

It would be running fine then suddenly we would get the “Reduced Performance” message and lose almost all throttle response. The car would hardly get out of its own way. Scary when driving at night on a busy freeway. Shutting the engine off and restarting would restore performance. My local Indy Volvo pro said he had never seen a Bosch unit go bad, but I didn’t listen to him and went a bought a new one. I now believe I have a good used one sitting on the shelf.

Thanks for the input. I got a new Bosch unit on order from FCP Euro but will hold off on using it until I have more info from the shop

[DavidE7]

I have had two of the Bosch electronic throttle bodies go bad in Volvos with over 200,000 miles. Unfortunately I don't remember the codes that were on VIDA in either car. I remember it wasn't a direct code saying the throttle was bad. I picked up junkyard replacement throttles with less than 150,000 miles on the oil change sticker and both cars have been good for 20,000 miles+. I spray inside the electrical connectors with electrical connector cleaner and then lube the pins with dielectric grease. Also replace the convoluted wire protection if it is bad because rodents will eat the wire insulation. Good luck.

[jonesg]

“… What were your symptoms that led to you replacing the throttle body? Similar to what I'm seeing? Or did the throttle body not respond at all…”

It would be running fine then suddenly we would get the “Reduced Performance” message and lose almost all throttle response. The car would hardly get out of its own way. Scary when driving at night on a busy freeway. Shutting the engine off and restarting would restore performance. My local Indy Volvo pro said he had never seen a Bosch unit go bad, but I didn’t listen to him and went a bought a new one. I now believe I have a good used one sitting on the shelf.

possible scenario, the ecm gets mismatched TB signal feedback,
It uses 2 signals, digital and analog.
a mismatch between the two trips limp mode.

The problem is all the above can be caused by something else.

[bradm612]

Took to an experienced Volvo guy who serviced the Volvo I had years ago. He said it is the throttle body so I'm going to replace it. I'll update after that comes in.

[bradm612]

Quick update. new throttle body fixed the issue. Don't quite understand it but maybe I got some carb cleaner into the electronic portion of the throttle body? It's running great now so I guess I won't put too much thought into it