Can't set the timing on the c70 engine

There is no reset button on a C70 Volvo, or any other Volvo for that matter.

on google:

2001 Volvo C70 Problems - RepairPal

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#1 Plug is the one closest to the Timing Belt on the Passenger Side end of the Engine.

Mileage on timing belt, depends on year ? make (volvo) model (c70) and engine size?. heres a couple of mileage readings,the 1998 c70 with a 2.3 turbo engine is due every 70,000 miles. the 1999 -2001 c70 with 2.3 turbo is due every 105,000 miles. the 2002- 2004 c70 with the 2.3 engine is also at 105,000. the 1998 c70 with the 2.4 engine is due every 70,000 miles. the 1999-2001 c70 with the 2.4 engine is due every 105,000 miles. the 2002- 2004 c70 with the 2.4 engine is due every 105,000 miles. god luck hope this helps.

you will need to pay for any book, there's nothing free on a volvo.

not really critical, just snug it down. like 20ft lbs.

The same thing happened to my 99 C70. I had to replace coils, in the engine...has somewhat to do with the spark plug stuff. Cost me $600.
Also the electric seats go out, they are lame. I spent $150 fixing my driver side one time, then it went out again...and is stuck...but okay enough for me to drive, and I refuse to fix it again.

90% of the Time..Code 1171 is an 02 sensor. Other 5% Is a Mass Airflow Sensor.. And Last .. Fuel Pump.. If engine seems to run fine.. its an O2 sensor.. Thank you

Scroll down a bit

http://www.devicemanuals.com/guide/Automobile/Volvo/1999-Volvo-C70-Owner%27s-Manual-==TVRBM05UWTU=.html

please rate if this helps Thanx

Go to the dealer, it may just be a simple software download that is required. Had a similar problem, didnt charge me.