 1976 2.0 question, throttle body |
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| jimkelly |
 Jan 7 2006, 09:41 PM
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Delaware USA  Group: Members Posts: 4,969 Joined: 5-August 04 From: Delaware, USA Member No.: 2,460 Region Association: MidAtlantic Region  |
Up untill a few days ago my car was running fine but all of a sudden it started to back fire when I decelerated and starting it became difficult. One thing that has been found is the both the vaccum hoses - light blue and the red to the distributor - both pull vaccum at idle and both lose vaccum when giving the motor some throttle. The red is supposed to have little vaccum at idle and gain vaccum with added throttle - correct? We are thinking that my throttle body has gummed up hole some where but at this moment we don't know how the advance hose nipple is plumbed in the 1976 2.0 throttle body - anyone got any ideas or a detailed drawing of how the advance vaccum flows through it? Thanks, Jim
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| Rand |
Jan 9 2006, 04:33 PM
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Cross Member Group: Members Posts: 7,409 Joined: 8-February 05 From: OR Member No.: 3,573 Region Association: None |
I don't mean to beat a dead horse, but this is normal. A port at the air distribution box, below the butterfly, will have maximum vacuum at idle but drop off as the butterfly opens. The engine is sucking a lot of air. Put a vacuum port in the intake below the butterfly, close the butterfly, and that port will pull a hard vacuum. Open the butterfly and the path of least resistance is the throttle body, not that little port. Vacuum at the port drops. The hose at the port below the butterfly should go to the distributor retard. So at idle, it retards the timing. Your car does not need the advance side at all. Sorry for the rabbit trail... I know this doesn't solve your problem, but it seemed like a worthwhile sidetrack. Your problem may be elsewhere. |
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Posts in this topic
jimkelly 1976 2.0 question Jan 7 2006, 09:41 PM
jimkelly TB Jan 7 2006, 09:41 PM Bleyseng Advance hose from the dizzy is plugged and just la... Jan 8 2006, 12:15 AM jimkelly I could be mixed up but I think we determined that... Jan 9 2006, 01:36 PM r_towle I hate to say this...but check your MPS...pull off... Jan 9 2006, 02:20 PM jimkelly I have a spare MPS - I'll give that a try. Tha... Jan 9 2006, 02:43 PM Rand If you connect a vacuum gauge to that nipple with ... Jan 9 2006, 02:48 PM jimkelly We get a vaccum reading at idle - but it dropps of... Jan 9 2006, 02:50 PM Rand Vacuum at idle but not at throttle = port below bu... Jan 9 2006, 02:54 PM Dave_Darling <... Jan 9 2006, 02:55 PM jimkelly rand - yes - vaccum at idel - it drops off with th... Jan 9 2006, 03:03 PM r_towle the vacuum advance circuit would only need to prod... Jan 9 2006, 03:06 PM Rand 
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