Hi Mr. Faust,

You can help you diagnostic efforts if you have access to, or own, an OBD-II code reader compatiblw with the OBD-II data port in your 1997 Volvo 960:



This image may be from an 850 or newer:



An auto parts store has one or a couple of OBD-II code readers for you to use while you are their parking lot. What fault codes you get (write them down) can lead to a failed component that can be cause. Though finding the OBD-II codes for 1997 Volvo 960 may be a pain. I'll take a look as the 700-900 FAQ has no such info. Well, here is the sum-total info the FAQ has on Volvo 900-series OBD-II equipped:

https://www.brickboard.com/FAQ/700-900/EngineOBDCodes.htm#OBDIIScanners

Well, that really sucks. Unless you have the OBD-1 boxes in the engine bay under the hood near the strut tower. Yet that is apparently removed for 1996.

Yet we have PDF of the Volvo Data Piocmket Booklet that may have the OBD-II codes for your 1996 Volvo 960:

http://www.ohio.edu/people/ridgely/volvo_docs/Volvo_DataPocket_700-900.pdf

Diagnostic Codes begin on PDF page 71. Though there exist newer version of this guide someplace.

So, check the FAQ as we always say:

https://www.brickboard.com/FAQ/700-900/960_90Info.htm#96090SeriesInformation

Good info, yet not so 960/90 helpful, save for the 960/90 highlights:

https://www.brickboard.com/FAQ/700-900/EnginePerformanceSymptoms.htm

Most of this is more useful for up to 1995:

https://www.brickboard.com/FAQ/700-900/ElectricalIgnition.htm

https://www.brickboard.com/FAQ/700-900/EngineSensors.htm

https://www.brickboard.com/FAQ/700-900/FuelSystem.htm

https://www.brickboard.com/FAQ/700-900/EngineFuelinjection.htm

One of more of these FAQ pages will mention wire harness inspection. In most instances, you disconnect the battery (yet have the reset codes for the radio and other items handy), while researching the wire harness, and disconnect / reconnect connectors with a smear of DeoxIT (www.caig.com) either side.

A small, light key chain is best for the ignition switch.

There is a relay / fuse board, that I *guess* should be hidden (in front of) the center console ashtray.

The relay board, or platform, as most of the relays, like the fuel injection relay, as well as a host of relay that may have, so long as the relay works, corrosion between where it makes contact with the terminals in the platform that connect to the rest of the wire harness.

Dave Barton can help you:
http://www.240turbo.com/volvorelays.html

Some DeoxIT as the spray and the grease (www.caig.com) in these connection helps. Though they may only need a wiggle (disconnect / reconnect). The relay board is a serviceable item. If you see the plastic forming the board heat warped around any of the high current relays, you will have get into the underneath of it and make repairs and replace relays.

It can help to remove and reinstall fuses.

Though specific solution or more to your symptoms? I have none.

Also, if an unknown as to when, replace timing belts and idler tensioner pulley and engine coolant. Use the Volvo coolant as concentrate antifreeze and distilled water or 50/50 premix or the OEM equivalent (Xerex G05?). Not Prestone or like green stuff. Yet the Volvo pcioket guide says use Volvo branded green stuff and 'clean' water. Use distilled at the very least, never tap water.

Spook and other are best to answer your questions, I'll guess?

Just had to jaw Volvo for a spell.

Questions?

Hope that helps.

MacDuffed.
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