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conflicting spark plug gap sizes Topic is solved

Help, Advice and DIY Tutorials on Volvo's P80 platform cars -- Volvo's 1990s "bread and butter" cars -- powered by the ubiquitous and durable Volvo inline 5-cylinder engine.

1992 - 1997 850, including 850 R, 850 T-5R, 850 T-5, 850 GLT
1997 - 2000 S70, S70 AWD
1997 - 2000 V70, V70 AWD
1997 - 2000 V70-XC
1997 - 2004 C70
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CIK7  
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conflicting spark plug gap sizes

Post by CIK7 »

Lookeee me, Im not voted off the P80 island :lol:
I THINK almost all Volvos call for .028" spark plug gap size. I went on the Bosch website to find the right spark plug. Bosch 7955 apparently has (or had) .028" gap size. I already bought the spark plugs (after seeing the website) so i looked at the box for the part number- the gap size is .036"! Whats up with this??? I called Bosch. They said Volvo recommends .028" but its not required and Bosch makes OEM parts, not what Volvo recommends. Apparently this plug is made for hundreds of cars, not just Volvo. The guy said i shouldn't listen to what someone says on a forum which I think is an ignorant statement. According to them, website stated gap is incorrect. My thought: Does Volvo's specs and the mass of Volvo experienced customers not matter? My question: how do i go about this? Bosch said dont adjust the gap. *shrugs*
95 854 Turbo 258K, auto, current
09 Rav4 Ltd3.5Fwd, red, 208K, current
98 V GLE/SE red, 379k (277k), 5sp, trailer in progress...
05 CRV EX AWD, Navy, 170K/184k, sold
03 Accord 2dr V6 silver, 196K/214K, 6sp, t-boned, sold
98 S GT white, 175K, 5sp, sold
96 964 silver, 146K, diff&trans/engine self-destr, crushed 😭
98 XC black, 151K, flooded&bent rod, crushed
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erikv11  
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Post by erikv11 »

Did you measure them, are they actually 0.036? I'd adjust the gap to 0.028 or buy another plug that comes gapped to that.
'95 854 T-5R, Motronic 4.4, 185k
'98 V70, T5 tune-injectors-turbo, LPT engine, 304k, daily driver
'06 S60 R, 197k
'07 XC70, black, 205k
'07 XC70, willow green, 212k
'99 Camry V6 :shock: 153k
gone: '96 NA 850 210k, '98 NA V70 182k, '98 S70 NA 225k, '96 855 NA 169k
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SlowLane
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Post by SlowLane »

Just save yourself the headache and use genuine Volvo spark plugs. They aren't that much more expensive and are readily available from IPD and FCP

Bosch plug quality has gone down the crapper in recent years. I've had a few which come right out of the box with the insulator actually loose in the metal housing. You can grab the insulator and spin it in the metal housing.

For my Volvos I've been using genuine plugs for years with zero issue. For my venerable air-cooled VW I have switched to NGKs and couldn't be happier. Bosch is dead to me, at least as far as spark plugs go.
Current Volvos:
2014 T6 XC70 - Turning into an expensive lesson.
2002 2.9 S80 - Wife's car, the "Silver Flash"
1996 855 Turbo - Formerly daughter's ride. My toy now.

Former Volvos:
1997 855 GLT - Totalled by daughter. Now she appreciates Volvos. :wink:
1984 244 DL B23F - warped head after radiator blew
1982 245 GL B21A - My first Volvo. Sold with 400,000 km on it.

Other:
1981 VW Westfalia - Californiated Canadian
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volvolugnut
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Post by volvolugnut »

See this post for comments on plugs:https://www.myvolvoparts.com/Genuine-Vo ... _b_40.html

Not on MVS, but seems reasonable advice to me.

You can regap plugs by tapping gently on the bottom of the side electrode. Measure the gap with wire gauge - not flat gauge. The wire should pull through with slight pressure at correct gap.
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Azik09
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Post by Azik09 »

Just an example. Different manufacturers define different spark plug gaps for same engine.
Attachments
gap.jpg
If my English is bad, please correct me :oops:
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