 1.7 Rebuild Bogging |
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| clow |
 Apr 12 2011, 02:28 PM
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#1
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The Kid  Group: Members Posts: 164 Joined: 7-September 10 From: Ontario, Canada Member No.: 12,151 Region Association: Canada  |
Hi, I just rebuilt a 1.7 EFI all stock. The car run nice at idle but as soon as I press the throttle it bogs out. If it doesn't bog it has just enough power to move the car. The plugs look fine. Is this a vacuum problem or a fuel problem? Any thought?
I am looking forward to the first drive. The weather if beautiful. Thanks, Clow |
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| mgphoto |
Apr 12 2011, 04:48 PM
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#2
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"If there is a mistake it will find me" Group: Members Posts: 1,339 Joined: 1-April 09 From: Los Angeles, CA Member No.: 10,225 Region Association: Southern California |
Sounds like the TPS (throttle positioning switch) needs to be adjusted, also check FI points in the dizzy they may need to be cleaned.
Good luck, Mike |
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| mgphoto |
Apr 12 2011, 04:51 PM
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#3
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"If there is a mistake it will find me" Group: Members Posts: 1,339 Joined: 1-April 09 From: Los Angeles, CA Member No.: 10,225 Region Association: Southern California |
QUOTE(mgphoto @ Apr 12 2011, 03:48 PM)  Sounds like the TPS (throttle positioning switch) needs to be adjusted, also check FI points in the dizzy they may need to be cleaned. Good luck, Mike try this link http://www.914world.com/bbs2/index.php?sho...c=95583&hl= |
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| luskesq |
Apr 12 2011, 05:07 PM
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#4
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Member Group: Members Posts: 276 Joined: 24-October 10 From: Fresno, CA Member No.: 12,303 Region Association: Central California |
Although you say the plugs look okay, are all of them firing? Timing could also be an issue with poor power.
keith |
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| clow |
Apr 12 2011, 05:09 PM
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#5
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The Kid Group: Members Posts: 164 Joined: 7-September 10 From: Ontario, Canada Member No.: 12,151 Region Association: Canada |
QUOTE(mgphoto @ Apr 12 2011, 02:51 PM) QUOTE(mgphoto @ Apr 12 2011, 03:48 PM) Sounds like the TPS (throttle positioning switch) needs to be adjusted, also check FI points in the dizzy they may need to be cleaned. Good luck, Mike try this link http://www.914world.com/bbs2/index.php?sho...c=95583&hl= Thanks, I tried a spare one and it did the same. I opened up the first one and the contacts are fine. |
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| TheCabinetmaker |
Apr 12 2011, 05:33 PM
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#6
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I drive my car everyday Group: Members Posts: 8,300 Joined: 8-May 03 From: Tulsa, Ok. Member No.: 666 |
Valves set wrong, timing way off, or dwell way off. Or, maybe all of the above.
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| TheCabinetmaker |
Apr 12 2011, 05:41 PM
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#7
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I drive my car everyday Group: Members Posts: 8,300 Joined: 8-May 03 From: Tulsa, Ok. Member No.: 666 |
QUOTE(clow @ Apr 12 2011, 05:09 PM) QUOTE(mgphoto @ Apr 12 2011, 02:51 PM) QUOTE(mgphoto @ Apr 12 2011, 03:48 PM) Sounds like the TPS (throttle positioning switch) needs to be adjusted, also check FI points in the dizzy they may need to be cleaned. Good luck, Mike try this link http://www.914world.com/bbs2/index.php?sho...c=95583&hl= Thanks, I tried a spare one and it did the same. I opened up the first one and the contacts are fine. Did you properly adjust it? |
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| Spoke |
Apr 12 2011, 08:04 PM
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#8
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Jerry Group: Members Posts: 6,983 Joined: 29-October 04 From: Allentown, PA Member No.: 3,031 Region Association: None 
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Does the engine rev up ok?
When you timed it, did you notice the mechanical advance? With the vacuum lines on the dizzy, did you notice the vacuum advance? I don't think it would be the FI points on the dizzy. All they do is tell the FI when to fire the injectors. Are all the cylinders firing? Check by touching the exhaust pipes near the muffler. Best done when the car is first fired up. |
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| clow |
Apr 12 2011, 08:08 PM
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#9
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The Kid Group: Members Posts: 164 Joined: 7-September 10 From: Ontario, Canada Member No.: 12,151 Region Association: Canada |
QUOTE(Spoke @ Apr 12 2011, 06:04 PM) Does the engine rev up ok? When you timed it, did you notice the mechanical advance? With the vacuum lines on the dizzy, did you notice the vacuum advance? I don't think it would be the FI points on the dizzy. All they do is tell the FI when to fire the injectors. Are all the cylinders firing? Check by touching the exhaust pipes near the muffler. Best done when the car is first fired up. Well I am going to go over the whole timing and distributor again. This has been mentioned a couple times. All cylinders are firing. I have been reading about odds and ends to do some I will give them a try. The push rod tubs started leaking...then oil started dripping and whoosh there was a fire. I had it rolled out in the driveway and it was put out in no time with the extinguisher, no damage. I am going to replace at the seals again just to be on the safe side so it looks like I can't get back to trouble shooting until this weekend. Thanks Clow |
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| 914itis |
Apr 12 2011, 09:09 PM
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#10
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Advanced Member Group: Members Posts: 2,892 Joined: 9-October 10 From: New York City Member No.: 12,256 Region Association: North East States |
QUOTE(vsg914 @ Apr 12 2011, 07:33 PM) Valves set wrong, timing way off, or dwell way off. Or, maybe all of the above. (IMG:style_emoticons/default/agree.gif) |
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| rick 918-S |
Apr 13 2011, 08:36 AM
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#11
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Hey nice rack! -Celette Group: Members Posts: 20,463 Joined: 30-December 02 From: Now in Superior WI Member No.: 43 Region Association: Northstar Region 
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Oil usually doesn't ignite. It will smoke and stink but flames? Guys run with leaking push rod tubes all the time and sometimes for years with no fire.
I would be checking for fuel leaks near the injectors. That's scary. I would also smell your oil to see if you have fuel in it. Gas in your oil if leaked on the exhaust would flame up. To your first issue: Check your fuel pressure. Low pressure from a weak pump could allow the engine to idle but starve and stall or barely run with low power. Check the fuel line from the tank to the pump (the suction side) for leaks. Under draw it could be acting like a drinking straw with a hole in it. Check the clamps on the suction side as well. Check all vacum hoses with a squirt bottle of water. The full length of the hose. Some guys use things like carb or brakes cleaner or starting fluid but it sounds like you already had one fire too many and it's possible your extinguisher is in need of a fill now so a second fire may not be an option. Be sure the vacum hoses are connected correctly. |
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| FourBlades |
Apr 13 2011, 08:57 AM
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#12
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From Wreck to Rockin Group: Members Posts: 2,054 Joined: 3-December 07 From: Brevard, FL Member No.: 8,414 Region Association: South East States
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Rick, How do you check the vacuum hoses using a squirt bottle? Spray water and look for bubbles? Thanks, John |
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