Runs for a Second and Dies, 1.8fi Starts, Runs for a Second, then Dies. |
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Runs for a Second and Dies, 1.8fi Starts, Runs for a Second, then Dies. |
CYCPYT |
Mar 25 2024, 07:42 AM
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#1
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Newbie Group: Members Posts: 16 Joined: 9-February 23 From: Culleoka Member No.: 27,149 Region Association: NineFourteenerVille |
Any advice on a forum article I should go to, or advice on how to troubleshoot this would be appreciated.
I have replaced the fuel filter and fuel pump, as I originally thought it was a fuel issue. Now I am not sure. Thank you! |
FlacaProductions |
Mar 25 2024, 08:23 AM
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#2
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Senior Member Group: Members Posts: 1,584 Joined: 24-November 17 From: LA Member No.: 21,628 Region Association: Southern California |
This thread here is a good start. If you can do a complete list of what you've done, specifics about the car, etc...
Are we talking literally one second or? And welcome to 914World - this place will get you set up... |
rfinegan |
Mar 25 2024, 10:23 AM
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#3
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Senior Member Group: Members Posts: 973 Joined: 8-February 13 From: NC Member No.: 15,499 Region Association: MidAtlantic Region |
I had a similar symptom on my 2.0 DJet( know is different ) but crank start and die....If I continue to pump the pedal in different location of open while staring and running the engine wold continue to run "like pumping and an accelerator pump” the root cause end up being the CHT sensor on/ @ 3 cly. I replaced the sensor and starts and runs great after the change.
GOOD place to start looking... |
Geezer914 |
Mar 25 2024, 10:45 AM
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#4
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Geezer914 Group: Members Posts: 1,409 Joined: 18-March 09 From: Salem, NJ Member No.: 10,179 Region Association: North East States |
I had a similar issue when I rebuilt my 1.8L to a 2056. It was a huge vacuum leak. Do a smoke test. You can make a smoker for under $10.
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dr914@autoatlanta.com |
Mar 25 2024, 11:55 AM
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#5
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914 Guru Group: Members Posts: 7,856 Joined: 3-January 07 From: atlanta georgia Member No.: 7,418 Region Association: None |
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fiacra |
Mar 25 2024, 01:42 PM
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#6
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Person.Woman.Man.Camera.TV Group: Members Posts: 321 Joined: 1-March 19 From: East Bay Region - California Member No.: 22,920 Region Association: Northern California |
I gather you are looking to be directed to a troubleshooting thread? The search function on 914World is not the most efficient. Best to use Google. Type in "914World" and then your question/search terms. That will usually get you where you need to be on this site.
If you are looking for direct advice, there are so many questions.....Give more information if you want help. 1) What made you think it was a fuel problem? Did you check fuel pressure/flow first? Just replacing the fuel pump and filter is not a guaranteed fix for a fuel problem. There are many other components to the system. Given that it runs for a second and then shuts off it could be that the double relay is initially firing the fuel pump but then the fuel pump is not being given power after the ignition is turned to the run position. Check your repair manual for how to test the system. Very briefly, push open the air flap at the AFM and see if the fuel pump starts to run. That's only one quick example of part of the diagnostic procedure for the fuel system on an L-Jet car. 2) What's the background on the car? Was it a good running driver before this happened? Has it sat for years? 3) Did you do any work on the car and now it won't start? 4) What have to do so far to diagnose the problem? You'll get lots of advice here. People are very willing to help and the hive mind has a lot of collective knowledge. Can't argue with starting with a smoke test as the L-Jet system relies on vacuum. Good luck!!! I'm sure you'll get this fixed. |
technicalninja |
Mar 25 2024, 01:57 PM
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#7
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Senior Member Group: Members Posts: 1,213 Joined: 31-January 23 From: Granbury Texas Member No.: 27,135 Region Association: Southwest Region |
Quicky technician tip...
Can you run it for more than 1 second on B12 carb spray? I'll try that early on to prove I have capable ignition and compression. I once bought a ratty 99 Miata that had sat dormant for 10 years as an organ doner. Opening the gas cap would make you retch... Completely destroyed fuel system! I disabled fuel pump, popped air inlet off, fired it on B12, and got it up to temperature. Proved engine good. And, when the car was parked the AC was left on. Proved AC function as well! If it will run on an alternate fuel source you have ruled out many things... |
StarBear |
Mar 25 2024, 02:27 PM
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#8
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Senior Member Group: Members Posts: 1,882 Joined: 2-September 09 From: NJ Member No.: 10,753 Region Association: North East States |
Make sure the harness plug is attached to the AFM. The cold start valve I think gives it a shot then then stops since no AFM circuit. When working on it, we often forget to reattach it as it slips down into the engine compartment.
Agree that more background would be helpful. |
CYCPYT |
Mar 25 2024, 04:31 PM
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#9
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Newbie Group: Members Posts: 16 Joined: 9-February 23 From: Culleoka Member No.: 27,149 Region Association: NineFourteenerVille |
This thread here is a good start. If you can do a complete list of what you've done, specifics about the car, etc... Are we talking literally one second or? And welcome to 914World - this place will get you set up... Thank you so much! I have not done anything to the car other than the fuel filter and fuel pump. Bought the car out of Cali, put about 1500 miles on it and this happened... It will stay alive for 2-5 seconds before it dies. It starts relatively easily, just won't stay running. I was thinking about doing the plugs wires and coil, since I don't know their age. Any advice is greatly appreciated. |
CYCPYT |
Mar 25 2024, 04:33 PM
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#10
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Newbie Group: Members Posts: 16 Joined: 9-February 23 From: Culleoka Member No.: 27,149 Region Association: NineFourteenerVille |
I had a similar symptom on my 2.0 DJet( know is different ) but crank start and die....If I continue to pump the pedal in different location of open while staring and running the engine wold continue to run "like pumping and an accelerator pump” the root cause end up being the CHT sensor on/ @ 3 cly. I replaced the sensor and starts and runs great after the change. GOOD place to start looking... Thank you, I will put this on the list of things to check. |
CYCPYT |
Mar 25 2024, 04:35 PM
Post
#11
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Newbie Group: Members Posts: 16 Joined: 9-February 23 From: Culleoka Member No.: 27,149 Region Association: NineFourteenerVille |
I had a similar issue when I rebuilt my 1.8L to a 2056. It was a huge vacuum leak. Do a smoke test. You can make a smoker for under $10. Thank you, I think that this is probable. I think I am going to just replace all the vacuum lines, again as I do not know their age. |
CYCPYT |
Mar 25 2024, 04:35 PM
Post
#12
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Newbie Group: Members Posts: 16 Joined: 9-February 23 From: Culleoka Member No.: 27,149 Region Association: NineFourteenerVille |
Make sure the harness plug is attached to the AFM. The cold start valve I think gives it a shot then then stops since no AFM circuit. When working on it, we often forget to reattach it as it slips down into the engine compartment. Agree that more background would be helpful. Thank you, I will check this out also. |
CYCPYT |
Mar 25 2024, 04:37 PM
Post
#13
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Newbie Group: Members Posts: 16 Joined: 9-February 23 From: Culleoka Member No.: 27,149 Region Association: NineFourteenerVille |
Quicky technician tip... Can you run it for more than 1 second on B12 carb spray? I'll try that early on to prove I have capable ignition and compression. I once bought a ratty 99 Miata that had sat dormant for 10 years as an organ doner. Opening the gas cap would make you retch... Completely destroyed fuel system! I disabled fuel pump, popped air inlet off, fired it on B12, and got it up to temperature. Proved engine good. And, when the car was parked the AC was left on. Proved AC function as well! If it will run on an alternate fuel source you have ruled out many things... I will give this a shot as well, thank you. |
CYCPYT |
Mar 25 2024, 04:42 PM
Post
#14
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Newbie Group: Members Posts: 16 Joined: 9-February 23 From: Culleoka Member No.: 27,149 Region Association: NineFourteenerVille |
I gather you are looking to be directed to a troubleshooting thread? The search function on 914World is not the most efficient. Best to use Google. Type in "914World" and then your question/search terms. That will usually get you where you need to be on this site. If you are looking for direct advice, there are so many questions.....Give more information if you want help. 1) What made you think it was a fuel problem? Did you check fuel pressure/flow first? Just replacing the fuel pump and filter is not a guaranteed fix for a fuel problem. There are many other components to the system. Given that it runs for a second and then shuts off it could be that the double relay is initially firing the fuel pump but then the fuel pump is not being given power after the ignition is turned to the run position. Check your repair manual for how to test the system. Very briefly, push open the air flap at the AFM and see if the fuel pump starts to run. That's only one quick example of part of the diagnostic procedure for the fuel system on an L-Jet car. 2) What's the background on the car? Was it a good running driver before this happened? Has it sat for years? 3) Did you do any work on the car and now it won't start? 4) What have to do so far to diagnose the problem? You'll get lots of advice here. People are very willing to help and the hive mind has a lot of collective knowledge. Can't argue with starting with a smoke test as the L-Jet system relies on vacuum. Good luck!!! I'm sure you'll get this fixed. Thank you, I have a lot of testing in front of me. I just did not know where to start. I thought since it starts and dies, I went immediately to fuel in my mind, that may have been shortsighted. I figured I would knock out some of the easier things that I thought I would be replacing anyway not knowing age or true condition. And then rather than reinventing the wheel, ask the jockeys that have been here before me and better at it. |
CYCPYT |
Mar 25 2024, 04:43 PM
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#15
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Newbie Group: Members Posts: 16 Joined: 9-February 23 From: Culleoka Member No.: 27,149 Region Association: NineFourteenerVille |
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emerygt350 |
Mar 25 2024, 05:09 PM
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#16
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Advanced Member Group: Members Posts: 2,096 Joined: 20-July 21 From: Upstate, NY Member No.: 25,740 Region Association: North East States |
Good idea to start with a vacuum leak search.
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wonkipop |
Mar 25 2024, 05:38 PM
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#17
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Advanced Member Group: Members Posts: 4,296 Joined: 6-May 20 From: north antarctica Member No.: 24,231 Region Association: NineFourteenerVille |
Any advice on a forum article I should go to, or advice on how to troubleshoot this would be appreciated. I have replaced the fuel filter and fuel pump, as I originally thought it was a fuel issue. Now I am not sure. Thank you! is this A) a car that has been sitting for a while/long time and not been run. and you are attempting to start it and bring it back to life. or B) has this problem suddenly developed in a running car. if its A) then then the symptoms fit this scenario. its starting and running off the cold start injector. it will run 5-10 seconds on the squirt it gets from that. but then it dies because the 4 main injectors are not opening. they are clogged or corroded closed and cannot spray. to check, pull an injector and crank the engine - confirm they are spraying. if not A) and its developed suddenly let us know. can think further. |
wonkipop |
Mar 25 2024, 05:47 PM
Post
#18
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Advanced Member Group: Members Posts: 4,296 Joined: 6-May 20 From: north antarctica Member No.: 24,231 Region Association: NineFourteenerVille |
This thread here is a good start. If you can do a complete list of what you've done, specifics about the car, etc... Are we talking literally one second or? And welcome to 914World - this place will get you set up... Thank you so much! I have not done anything to the car other than the fuel filter and fuel pump. Bought the car out of Cali, put about 1500 miles on it and this happened... It will stay alive for 2-5 seconds before it dies. It starts relatively easily, just won't stay running. I was thinking about doing the plugs wires and coil, since I don't know their age. Any advice is greatly appreciated. ah - i see the problem developed suddenly. as @StarBear has noted - its firing off the cold start injector. thats the 2-5 seconds bit. a bit more info needed. take a couple of good shots of the engine bay and post them up here. you need to be methodical with the old fuel injection systems. but its surprisingly simple. esp these early L jets. the correct vac hose diagrams for the 74 1.8s (both USA and Calif) are here. scroll down the page - towards bottom. http://www.914world.com/bbs2/index.php?sho...57407&st=40 the 75 1.8s are not very different and if you have one i can let you know what is changed from 74. its probably a good idea to down load these - you may as well. from jeff bowlsby's website there is this little guide to L jet troubleshooting. helps you be methodical and gives you a reference to read if you can't understand what might be suggested by members here. https://bowlsby.net/914/Classic/zTN_Man12.pdf and of course these are super handy. pdf files for the entire 914 factory workshop manual set. the fuel injection stuff is group 2 (4 cylinder cars). but if you have the ability with internet connection download the lot. tells you just about everything you might need to know to do anything on the car. http://p914-6info.net/Manuals.htm |
jhynesrockmtn |
Mar 26 2024, 08:02 AM
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#19
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Member Group: Members Posts: 418 Joined: 13-June 16 From: spokane wa Member No.: 20,100 Region Association: Pacific Northwest |
I'll offer this. I bought my 70 1.7 a few years ago. It had sat for a long time. I refreshed fuel lines, filter, pump, etc. It ran fine for a while. Then it started to die after starting. My fuel tank was rusty inside and the sediment was plugging the in tank screen. The only thing I can think of is the more I drove it, the more things broke free in the tank. A tank reseal and new sock solved it.
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fiacra |
Mar 26 2024, 09:41 AM
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#20
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Person.Woman.Man.Camera.TV Group: Members Posts: 321 Joined: 1-March 19 From: East Bay Region - California Member No.: 22,920 Region Association: Northern California |
This thread here is a good start. If you can do a complete list of what you've done, specifics about the car, etc... Are we talking literally one second or? And welcome to 914World - this place will get you set up... Thank you so much! I have not done anything to the car other than the fuel filter and fuel pump. Bought the car out of Cali, put about 1500 miles on it and this happened... It will stay alive for 2-5 seconds before it dies. It starts relatively easily, just won't stay running. I was thinking about doing the plugs wires and coil, since I don't know their age. Any advice is greatly appreciated. I STRONGLY recommend you don't start replacing parts BEFORE you diagnose the problem. That will just muddy the water and potentially make it much more difficult to figure out what is going on. I get the impulse to start doing all the work you had intended to do before this problem happened, but it won't be productive to do it before you figure out what is causing your current problem. Figure out what is defective first, get the car running, and then start on any deferred maintenance. Once you start firing the parts cannon at the problem you are on a very slippery slope.... |
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