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tsvo |
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#1
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Member ![]() ![]() Group: Members Posts: 123 Joined: 30-January 16 From: Chicago Member No.: 19,616 Region Association: Upper MidWest ![]() ![]() |
I have a 1973, 1.7 with FI still on it. The car is stalling at idle after the engine warms up. Any ideas what to adjust or look for? Things that may be contributing, but not sure. I think there is a vaccum leak. It smells like it is running rich. I recently replaced the fuel pump.
Any help is much appreciated. Thanks, Terry |
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mgphoto |
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#2
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"If there is a mistake it will find me" ![]() ![]() ![]() Group: Members Posts: 1,375 Joined: 1-April 09 From: Los Angeles, CA Member No.: 10,225 Region Association: Southern California ![]() |
I have a 1973, 1.7 with FI still on it. The car is stalling at idle after the engine warms up. Any ideas what to adjust or look for? Things that may be contributing, but not sure. I think there is a vaccum leak. It smells like it is running rich. I recently replaced the fuel pump. Any help is much appreciated. Thanks, Terry Check the MPS, see if it holds vacuum and for how long. Air leak would cause fast idle. Check for kinked fuel line? |
tsvo |
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#3
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Member ![]() ![]() Group: Members Posts: 123 Joined: 30-January 16 From: Chicago Member No.: 19,616 Region Association: Upper MidWest ![]() ![]() |
I have a 1973, 1.7 with FI still on it. The car is stalling at idle after the engine warms up. Any ideas what to adjust or look for? Things that may be contributing, but not sure. I think there is a vaccum leak. It smells like it is running rich. I recently replaced the fuel pump. Any help is much appreciated. Thanks, Terry Check the MPS, see if it holds vacuum and for how long. Air leak would cause fast idle. Check for kinked fuel line? Thank you |
Rand |
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#4
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Cross Member ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 7,411 Joined: 8-February 05 From: OR Member No.: 3,573 Region Association: None ![]() |
(IMG:style_emoticons/default/agree.gif)
Vacuum leaks on Djet usually cause high idle. An exception is the MPS which fails to full rich if it doesn't hold a vacuum (whether via the hose or the diaphragm within). If you pull the vacuum hose off the MPS while it's running, what changes? |
thelogo |
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#5
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Senior Member ![]() ![]() ![]() Group: Retired Members Posts: 1,510 Joined: 6-April 10 Member No.: 11,572 Region Association: None ![]() |
Once d jet stops working .
The really problem could be anywhere And beyond guessing and hopeing There is no way to test or identifyi the issue or soultion short of replacing or rebuilding all components that are nla So if it still runs it is in some form of compromised Performance aka limp mode . I love it when something that supposed to last 10 years go's strong for 50yrs. And when it fails it fails slowly (Djet) But I hate it when cars or planes catch on fire Don't ignore the warning signs |
Rand |
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#6
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Cross Member ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 7,411 Joined: 8-February 05 From: OR Member No.: 3,573 Region Association: None ![]() |
Ignore the last post. Djet is a great system. It starts and runs perfectly at all altitudes. Just because someone doesn't understand it doesn't mean it's bad. Sure, he likes carbs (IMG:style_emoticons/default/laugh.gif)
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phatnine11 |
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#7
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Member ![]() ![]() Group: Members Posts: 286 Joined: 22-March 05 From: Rancho Cucamonga, CA Member No.: 3,798 ![]() |
Won't idle when the engine warms up? I would check the AAR valve, very easy to do. Use a pair of vice grip pliers and clamp off the hose that runs from the air cleaner to the valve. If the car idles now, the problem is with the valve. I would look up the procedures for testing/ cleaning the valve. Without going into too much detail, this valve needs 12 volts to operate correctly. sometimes they freeze up.
Good luck, Phatnine11 |
buck toenges |
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#8
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Senior Member ![]() ![]() ![]() Group: Members Posts: 553 Joined: 25-November 03 From: Fort wayne In Member No.: 1,388 Region Association: None ![]() ![]() |
Does the 1973 1.7 have the air intake temp sensor that hooks into the plenum? It is by the throttle body. The 1973 2.0L has it. If the 1.7L has it, disconnect it from the wiring harness. The pet catalog says that it is part of the 1.7L. That will up the rpms slightly. That is what I did when my 2.0L engine warmed up and started to stumble and lose rpms at idle. Brad Mayeur told me that with these old engines you can't always find the answer on issues and that the tps 1 sensor isn't needed. He says it lowers mpg but the rpms at idle improves.
The part number is 311906081a Buck |
914_teener |
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#9
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914 Guru ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 5,264 Joined: 31-August 08 From: So. Cal Member No.: 9,489 Region Association: Southern California ![]() |
I have a 1973, 1.7 with FI still on it. The car is stalling at idle after the engine warms up. Any ideas what to adjust or look for? Things that may be contributing, but not sure. I think there is a vaccum leak. It smells like it is running rich. I recently replaced the fuel pump. Any help is much appreciated. Thanks, Terry Check the MPS, see if it holds vacuum and for how long. Air leak would cause fast idle. Check for kinked fuel line? +1 And... Ignore the Trolls. |
thelogo |
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#10
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Senior Member ![]() ![]() ![]() Group: Retired Members Posts: 1,510 Joined: 6-April 10 Member No.: 11,572 Region Association: None ![]() |
Once d jet stops working . The really problem could be anywhere And beyond guessing and hopeing There is no way to test or identifyi the issue or soultion short of replacing or rebuilding all components that are nla So if it still runs it is in some form of compromised Performance aka limp mode . I love it when something that supposed to last 10 years go's strong for 50yrs. And when it fails it fails slowly (Djet) But I hate it when cars or planes catch on fire Don't ignore the warning signs (IMG:style_emoticons/default/smoke.gif) hey you dont have to trust me Just listen to what im saying to you When djet parts and techs are plentful I will stop being a fan of carbs aka (dead tech) |
tsvo |
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#11
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Member ![]() ![]() Group: Members Posts: 123 Joined: 30-January 16 From: Chicago Member No.: 19,616 Region Association: Upper MidWest ![]() ![]() |
(IMG:style_emoticons/default/agree.gif) Vacuum leaks on Djet usually cause high idle. An exception is the MPS which fails to full rich if it doesn't hold a vacuum (whether via the hose or the diaphragm within). If you pull the vacuum hose off the MPS while it's running, what changes? Thank you, I will be working on it this weekend. I appreciate your help. |
tsvo |
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#12
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Member ![]() ![]() Group: Members Posts: 123 Joined: 30-January 16 From: Chicago Member No.: 19,616 Region Association: Upper MidWest ![]() ![]() |
(IMG:style_emoticons/default/agree.gif) Vacuum leaks on Djet usually cause high idle. An exception is the MPS which fails to full rich if it doesn't hold a vacuum (whether via the hose or the diaphragm within). If you pull the vacuum hose off the MPS while it's running, what changes? Thank you |
tsvo |
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#13
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Member ![]() ![]() Group: Members Posts: 123 Joined: 30-January 16 From: Chicago Member No.: 19,616 Region Association: Upper MidWest ![]() ![]() |
Does the 1973 1.7 have the air intake temp sensor that hooks into the plenum? It is by the throttle body. The 1973 2.0L has it. If the 1.7L has it, disconnect it from the wiring harness. The pet catalog says that it is part of the 1.7L. That will up the rpms slightly. That is what I did when my 2.0L engine warmed up and started to stumble and lose rpms at idle. Brad Mayeur told me that with these old engines you can't always find the answer on issues and that the tps 1 sensor isn't needed. He says it lowers mpg but the rpms at idle improves. The part number is 311906081a Buck Thank you, I will be working on it this weekend. I appreciate your help. |
tsvo |
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#14
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Member ![]() ![]() Group: Members Posts: 123 Joined: 30-January 16 From: Chicago Member No.: 19,616 Region Association: Upper MidWest ![]() ![]() |
(IMG:style_emoticons/default/agree.gif) Vacuum leaks on Djet usually cause high idle. An exception is the MPS which fails to full rich if it doesn't hold a vacuum (whether via the hose or the diaphragm within). If you pull the vacuum hose off the MPS while it's running, what changes? Thank you, I will be working on it this weekend. I appreciate your help. |
windforfun |
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#15
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Advanced Member ![]() ![]() ![]() ![]() Group: Members Posts: 2,054 Joined: 17-December 07 From: Blackhawk, CA Member No.: 8,476 Region Association: None ![]() ![]() |
I simply raised the idle to about 1,500 rpm when cold. After it warms up, the idle drops to about 1,000 rpm & stays there.
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dr914@autoatlanta.com |
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#16
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914 Guru ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 8,161 Joined: 3-January 07 From: atlanta georgia Member No.: 7,418 Region Association: None ![]() |
check the dwell angle first, closed points make many assume that they have a fuel injection problem. After that check to see that the engine is running on all four cylinders then check to see if the pressure sensor is leaking vacuum causing too rich a mixture
I have a 1973, 1.7 with FI still on it. The car is stalling at idle after the engine warms up. Any ideas what to adjust or look for? Things that may be contributing, but not sure. I think there is a vaccum leak. It smells like it is running rich. I recently replaced the fuel pump. Any help is much appreciated. Thanks, Terry |
tsvo |
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#17
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Member ![]() ![]() Group: Members Posts: 123 Joined: 30-January 16 From: Chicago Member No.: 19,616 Region Association: Upper MidWest ![]() ![]() |
check the dwell angle first, closed points make many assume that they have a fuel injection problem. After that check to see that the engine is running on all four cylinders then check to see if the pressure sensor is leaking vacuum causing too rich a mixture I have a 1973, 1.7 with FI still on it. The car is stalling at idle after the engine warms up. Any ideas what to adjust or look for? Things that may be contributing, but not sure. I think there is a vaccum leak. It smells like it is running rich. I recently replaced the fuel pump. Any help is much appreciated. Thanks, Terry Thank you, I will check your suggestions. I appreciate the response. |
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