Running really rich, 1973 1.7 FI |
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Running really rich, 1973 1.7 FI |
tbone1819 |
Jul 18 2017, 03:06 PM
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#1
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Newbie Group: Members Posts: 26 Joined: 1-February 17 From: Lynbrook NY Member No.: 20,800 Region Association: North East States |
Ok,
So my 73 was running great until it slowly started to go down hill. Car would not start after it was running/driving for a while but the next day would fire right up. Recenltly changed the oil that was completly diluted with gasoline. WTF?? |
BeatNavy |
Jul 18 2017, 03:24 PM
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#2
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Certified Professional Scapegoat Group: Members Posts: 2,919 Joined: 26-February 14 From: Easton, MD Member No.: 17,042 Region Association: MidAtlantic Region |
Ok, So my 73 was running great until it slowly started to go down hill. Car would not start after it was running/driving for a while but the next day would fire right up. Recenltly changed the oil that was completly diluted with gasoline. WTF?? Read this thread: http://www.914world.com/bbs2/index.php?sho...=312907&hl= It all applies, even though that's a 2.0. If you check some of those things and give us feedback we can help narrow it down. |
Dave_Darling |
Jul 18 2017, 04:45 PM
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#3
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914 Idiot Group: Members Posts: 14,974 Joined: 9-January 03 From: Silicon Valley / Kailua-Kona Member No.: 121 Region Association: Northern California |
Gas has washed past the rings and into the sump. Good thing you changed it; gasoline does not lubricate like oil does. This happens any time the mixture is rich enough that the engine almost doesn't run.
Things to check: Fuel pressure, disconnected wires (especially head temp sensor wire), MPS that won't hold vacuum, unplugged hoses... --DD |
tbone1819 |
Jul 18 2017, 07:35 PM
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#4
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Newbie Group: Members Posts: 26 Joined: 1-February 17 From: Lynbrook NY Member No.: 20,800 Region Association: North East States |
Ok, So my 73 was running great until it slowly started to go down hill. Car would not start after it was running/driving for a while but the next day would fire right up. Recenltly changed the oil that was completly diluted with gasoline. WTF?? Read this thread: http://www.914world.com/bbs2/index.php?sho...=312907&hl= It all applies, even though that's a 2.0. If you check some of those things and give us feedback we can help narrow it down. Thanks a whole lot! |
tbone1819 |
Jul 18 2017, 07:36 PM
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#5
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Newbie Group: Members Posts: 26 Joined: 1-February 17 From: Lynbrook NY Member No.: 20,800 Region Association: North East States |
Gas has washed past the rings and into the sump. Good thing you changed it; gasoline does not lubricate like oil does. This happens any time the mixture is rich enough that the engine almost doesn't run. Things to check: Fuel pressure, disconnected wires (especially head temp sensor wire), MPS that won't hold vacuum, unplugged hoses... --DD Thanks I will check that out. |
BK911 |
Jul 19 2017, 08:20 AM
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#6
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Senior Member Group: Members Posts: 672 Joined: 19-February 04 From: Rocky Top, TN Member No.: 1,674 Region Association: None |
Check mps vacuum first.
Pretty easy to do and good chance that's the issue. |
tbone1819 |
Jul 19 2017, 03:55 PM
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#7
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Newbie Group: Members Posts: 26 Joined: 1-February 17 From: Lynbrook NY Member No.: 20,800 Region Association: North East States |
Ok, So my 73 was running great until it slowly started to go down hill. Car would not start after it was running/driving for a while but the next day would fire right up. Recenltly changed the oil that was completly diluted with gasoline. WTF?? Read this thread: http://www.914world.com/bbs2/index.php?sho...=312907&hl= It all applies, even though that's a 2.0. If you check some of those things and give us feedback we can help narrow it down. Ok, so fuel pressure was 27 psi.....car starts with fuel pump disconected from the relay box after it has been primed...wtf? lol |
BeatNavy |
Jul 19 2017, 04:16 PM
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#8
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Certified Professional Scapegoat Group: Members Posts: 2,919 Joined: 26-February 14 From: Easton, MD Member No.: 17,042 Region Association: MidAtlantic Region |
Fuel pressure is not the issue then (it's probably low by a PSI - I think 28 PSI is spec).
Are you saying that you can disconnect the fuel pump relay (or connector) at the relay board and the car will start/run after initially turning the key and priming the fuel pump? Please explain in more detail. How long does it run that way? Once you prime the pump the fuel is going to be pressurized for at least a short period of time even if the pump isn't running, but it will bleed out quickly. Not sure why you disconnected fuel pump, but you still need to: 1. Verify MPS holds vacuum. 2. CHT is working properly and is connected to wiring harness properly. 3. Try with CSV disconnected. |
tbone1819 |
Jul 19 2017, 04:22 PM
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#9
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Newbie Group: Members Posts: 26 Joined: 1-February 17 From: Lynbrook NY Member No.: 20,800 Region Association: North East States |
Fuel pressure is not the issue then (it's probably low by a PSI - I think 28 PSI is spec). Are you saying that you can disconnect the fuel pump relay (or connector) at the relay board and the car will start/run after initially turning the key and priming the fuel pump? Please explain in more detail. How long does it run that way? Once you prime the pump the fuel is going to be pressurized for at least a short period of time even if the pump isn't running, but it will bleed out quickly. Not sure why you disconnected fuel pump, but you still need to: 1. Verify MPS holds vacuum. 2. CHT is working properly and is connected to wiring harness properly. 3. Try with CSV disconnected. The car runs for 1-2 seconds after being primed and then diconected. |
BeatNavy |
Jul 19 2017, 04:25 PM
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#10
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Certified Professional Scapegoat Group: Members Posts: 2,919 Joined: 26-February 14 From: Easton, MD Member No.: 17,042 Region Association: MidAtlantic Region |
Fuel pressure is not the issue then (it's probably low by a PSI - I think 28 PSI is spec). Are you saying that you can disconnect the fuel pump relay (or connector) at the relay board and the car will start/run after initially turning the key and priming the fuel pump? Please explain in more detail. How long does it run that way? Once you prime the pump the fuel is going to be pressurized for at least a short period of time even if the pump isn't running, but it will bleed out quickly. Not sure why you disconnected fuel pump, but you still need to: 1. Verify MPS holds vacuum. 2. CHT is working properly and is connected to wiring harness properly. 3. Try with CSV disconnected. The car runs for 1-2 seconds after being primed and then diconected. Ok, that sounds normal then. Your fuel system is pressurized when you prime the pump. |
whitetwinturbo |
Jul 19 2017, 10:58 PM
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#11
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Honey, does this wing make my ass look fat? Group: Members Posts: 1,391 Joined: 22-October 11 From: Newport Beach/Kalefornya/USA Member No.: 13,704 Region Association: Southern California |
If it goes down hill slowly ........ release the hand brake (IMG:style_emoticons/default/laugh.gif)
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