'71 Volvo Rough Idle - Automotive Repairs - DIY Chatroom Home Improvement Forum

Go Back   DIY Chatroom Home Improvement Forum > Do It Yourself > Automotive Repairs


Thread Tools Display Modes
Old 07-19-2013, 02:07 PM   #1
Join Date: Dec 2009
Location: Columbus, OH
Posts: 333
Rewards Points: 260

'71 Volvo rough idle

Hi all. I have a '71 Volvo 1800 that has a strange idling problem. When I first start it up, it idles fine, but then all of a sudden, around 30 seconds or so into idling, it drops down significantly. It's a 4 cylinder engine and 2 of the spark plugs have white tips, but all of the injectors are "squirting" appropriately. Does anyone have any idea why this might be happening? Thanks!



jpearson311 is online now   Reply With Quote
Old 07-21-2013, 07:52 PM   #2
ukrkoz's Avatar
Join Date: Dec 2010
Posts: 696
Rewards Points: 750

'71 Volvo rough idle

Go here:
Scroll down to color chart, find your plugs, and read what it means.
Wanted to say - you run lean on those 2 plugs, ha-ha, indeed:
A clean, white insulator firing tip and/or excessive electrode erosion indicates this spark plug condition. k This is often caused by over advanced ignition, timing, poor engine cooling system efficiency (scale, stoppages, low level), a very lean air/fuel mixture, or a leaking intake manifold. When these conditions prevail, even a plug of the correct heat range will overheat.
Clean fuel injectors.


ukrkoz is offline   Reply With Quote
Old 08-21-2013, 09:17 PM   #3
Join Date: Apr 2012
Location: Denton Tx
Posts: 35
Rewards Points: 25

'71 Volvo rough idle

Sounds like you have a vacuum leak. With the engine idling, spray mist of water around the engine area. The engine will start to die or run rough if the leaking area gets sprayed
msmith5554 is offline   Reply With Quote

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
Toilet and Shower Rough In Dimensions VikingDinKC Plumbing 16 05-13-2012 02:50 PM
1991 Pontiac 6000 v6 3.1l running rough Patriot_RAM Automotive Repairs 17 10-09-2010 05:00 AM
Basement Toilet Rough In - Help atm Plumbing 3 06-06-2009 12:04 PM
Rough Lawnmower idle. Please advise. Shaun_in_NC Landscaping & Lawn Care 2 01-01-2009 05:44 PM
'79 Jeep CJ7 rough idle Jeeper1970 Automotive Repairs 13 12-20-2008 07:12 PM

Top of Page | View New Posts