 Backfiring problem |
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| r_towle |
 May 28 2004, 07:30 PM
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#1
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Custom Member  Group: Members Posts: 24,705 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States 
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Hi,
72 1.7 liter DJet Timing set, dwell set, new plug, points and condensor. Valves just re-adjusted and checked again. It backfires through the throttle body... Low power, then surges as if it cleared its throught the backfiring again..... HELP Suggestions needed Rich |
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| TheCabinetmaker |
May 28 2004, 07:34 PM
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#2
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I drive my car everyday Group: Members Posts: 8,336 Joined: 8-May 03 From: Tulsa, Ok. Member No.: 666 |
Did you set the timing before setting the dwell?
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| r_towle |
May 28 2004, 07:39 PM
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#3
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Custom Member Group: Members Posts: 24,705 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States
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valves, dwell, timing in that order, always
Rich |
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| TheCabinetmaker |
May 28 2004, 07:47 PM
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#4
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I drive my car everyday Group: Members Posts: 8,336 Joined: 8-May 03 From: Tulsa, Ok. Member No.: 666 |
OK, just checking. Ya never know! Did this just start after the tune up?
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| r_towle |
May 28 2004, 07:49 PM
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#5
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Custom Member Group: Members Posts: 24,705 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States
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did it last year, tuned it up and it went away....
Last time I removed and re-greased the dizzy, that did it finally. Rich |
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| TheCabinetmaker |
May 28 2004, 08:02 PM
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#6
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I drive my car everyday Group: Members Posts: 8,336 Joined: 8-May 03 From: Tulsa, Ok. Member No.: 666 |
Well, sometimes it just don't make any sense, but if it worked once, I'd try it again. Ya just never know!
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| mike_the_man |
May 31 2004, 04:33 PM
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#7
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I like stuff! Group: Members Posts: 1,338 Joined: 11-June 03 From: Regina, Saskatchewan, Canada Member No.: 809 |
Could be the trigger points. There's no good way to test them, though. I was having a similar problem, and my heat exchangers were loose. Torqued them all to 16ft/lbs and it fixed it right up. Have you checked the plugs? It could be running lean or rich. I can never remember which one it is that makes it backfire.
Good luck, |
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| Bullet |
May 31 2004, 06:12 PM
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#8
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Member Group: Members Posts: 116 Joined: 16-April 04 From: Newberg, OR Member No.: 1,940 |
I always though that a backfire was cuased by the mixture in the combustion chaber being fired when the valves were open. Which would be a timming issue, or carbon build up that gets hot enough to light the mixture before it is ready.
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| efrenv |
May 31 2004, 11:25 PM
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#9
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Newbie Group: Members Posts: 35 Joined: 11-February 03 From: Claremont, California Member No.: 297 |
Had the same symptoms with my car. Adjusted valves and backfiring was minimized. Then adjusted the throttle position switch and it has not occurred lately (knock on wood). Good luck (IMG:style_emoticons/default/wink.gif)
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| Toast |
Jun 1 2004, 12:12 PM
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#10
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Not bad for carrying sway bars. Group: Members Posts: 3,380 Joined: 20-January 04 From: Las Vegas Member No.: 1,580 Region Association: Southwest Region |
QUOTE(mike_the_man @ May 31 2004, 02:33 PM) It could be running lean or rich. I can never remember which one it is that makes it backfire. Rich QUOTE Bullett.. I always though that a backfire was cuased by the mixture in the combustion chaber being fired when the valves were open. Which would be a timming issue, Thats because it is running too rich and extra gas is getting through that is burning off durring the spark. |
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