Volvo 850, S70, V70, C70 (until 1998) – How to change spark plugs

by: Alexandra M.

Follow these instructions to change the spark plugs on all Volvo 5 cylinder petrol engines from 1991 to 1998, Volvo models 850, S70, V70, C70 with 5 cylinder engines 2.0 10v, 2.0 20v,  2.4 10v, 2.4 20v,  2.5 10v, 2.5 20v, 2.0 Turbo, 2.4 Turbo, 2.5 Turbo, 2.3 Turbo T-5 and 2.3 Turbo R.

This tutorial don’t apply if your car is a 1999 or later S70, V70 or C70 petrol engine.

Tools you need:
1. 5 x New Spark plugs  (volvo part number: Turbo engines: 8692071  / Non-Turbo engines: 8642660 )
2. 16mm spark plug removal tool / socket
3. T30 torx socket
4. Magnetic tool

Be sure to order the right plugs for your engine, as Turbo engines use different spark plugs thatn non-Turbo ones.

Step 1 Remove the 6 T30 torx screws (marked red below) holding the engine cover in place.

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Step 2 Remove the cover pushing it up and sliding to the left

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Step 3 You’ll now see the HT leads that run to the spark plugs.

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Starting at cylinder 1, remove the HT lead by twisting it from side to side then pulling it from the boot whilst twisting. You should allways push on the rubber boot and never pull the lead of by the wire because you can damage the internals of the HT lead.

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Step 4 Once you have removed the lead from the spark plug hole you’ll be able to look down and see the plug itself. Use your plug removal tool (16mm size) to unbolt the spark plug.

volvo-850-s70-v70-c70-1998-change-spark-plugs 5

Once the plug is free you can use a magnetic tool to push it out of the hole

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Step 5 Inspect each plug as it comes out. They should all be the same or start investigating. If they are very black then you could be running rich, very white means probably running lean. New vs old in picture below

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Step 6 Re-install the new spark plug in place. Plugs nowadays already come gapped from the factory, so you usually won’t have to ‘gap’ the plug (set this distance between the centre electrode and the ground electrode). With the magnetic tool, gently place the plug straight into the well taking care not to damage it. Then first tighten the plug up by hand until you hit resistance and then tighten with your spark plug tool. Do not overtight them, once it offers some resistance, it’s ok.

Step 7 Repeat the procedure for the other 4 plugs. Once done, re-connect the HT leads and install the engine cover in place.

And you’re done!

The instructions in this tutorial will work in the following models / years:

– 1997, 1998 Volvo S70
– 1997, 1998 Volvo V70
– 1997, 1998 Volvo C70 Coupe and Convertible / Cabrio
– Volvo 850 T-5 225 hp B5234FT, made / sold in 1994, 1995, 1996 and 1997
– Volvo 850 T-5 R 240 hp B5234T5, made / sold in 1995
– Volvo 850 R 250 hp B5234T4, made / sold in 1996 and 1997
– Volvo 850 R Auto 240 hp B5234T5, made / sold in 1996 and 1997
– Volvo 850 2.3T 218 hp B5234T2, made / sold in 1995, 1996 and 1997
– Volvo 850 2.5T 193 hp B5254T, made / sold in 1997
– Volvo 850 GLT 2.0T 210 hp B5204FST, made / sold in 1994, 1995, 1996 and 1997
– Volvo 850 GLE 2.0T 180 hp B5204T2, made / sold in 1996 and 1997
– Volvo 850 2.0 20V 143 hp B5204FS, made / sold in 1992, 1993, 1994, 1995 and 1996
– Volvo 850 2.0 10V 126 hp B5202FS, made / sold in 1995, 1996 and 1997
– Volvo 850 2.5 20V 170 hp B5254FS LH 3.2, made / sold in 1992, 1993, 1994, 1995 and 1996
– Volvo 850 2.5 20V 170 hp B5254FS, made / sold in 1996 and 1997
– Volvo 850 2.5 10V 144 hp B5252FS, made / sold in 1993, 1994, 1995, 1996 and 1997
– Volvo 850 2.3 20V 144 hp B5234FS, made / sold in 1994, 1995, 1996 and 1997