Lost Power, No Fuel, Help! |
|
Porsche, and the Porsche crest are registered trademarks of Dr. Ing. h.c. F. Porsche AG.
This site is not affiliated with Porsche in any way. Its only purpose is to provide an online forum for car enthusiasts. All other trademarks are property of their respective owners. |
|
Lost Power, No Fuel, Help! |
Nogoodwithusernames |
Sep 28 2016, 01:57 PM
Post
#1
|
Member Group: Members Posts: 235 Joined: 31-May 16 From: Nor-Cal Member No.: 20,051 Region Association: None |
So I got all the fuel lines replaced and it's been running splendidly, decided to take it to work today. Just a minute away from work it would die at idle after the 30minute fwy run, but I got it re-started and got to work just keeping the throttle open a bit when stopped.
I had to run an errand and started to get onto the freeway again and lost all power. Pulled over, opened the decklid and much to my dismay one of the fuel lines had popped off the right side fuel rail. I attached and tightened all the lines/clamps outside the car so it wasn't loose but it's back on and nice and tight again. Tried to start it and nothing, cycle the pump a few times and crank. Nothing. It tried to start a few times but wouldn't run. Got it towed back to work and I've checked a few things when I've had time. There is fuel in the lines still, but I don't seem to be getting anything from the injectors. At least on the driver side where I pulled them out of the manifold. I did play with the connector on the distributor and it seems to be well seated, as do the connections on the injectors. I can't imagine that all four injectors would get clogged at the exact same time either, just seems a bit implausible. I don't see how losing fuel pressure would then keep the injectors from firing but anyone have any ideas? |
KELTY360 |
Sep 28 2016, 02:23 PM
Post
#2
|
914 Neferati Group: Members Posts: 5,029 Joined: 31-December 05 From: Pt. Townsend, WA Member No.: 5,344 Region Association: Pacific Northwest |
Have you checked the relay on the relay board?
|
Nogoodwithusernames |
Sep 28 2016, 02:34 PM
Post
#3
|
Member Group: Members Posts: 235 Joined: 31-May 16 From: Nor-Cal Member No.: 20,051 Region Association: None |
|
ndfrigi |
Sep 28 2016, 02:37 PM
Post
#4
|
Advanced Member Group: Members Posts: 2,928 Joined: 21-August 11 From: Orange County Member No.: 13,474 Region Association: Southern California |
what is the weather in your area now? maybe vapor locked on your fuel pump?
|
KELTY360 |
Sep 28 2016, 03:16 PM
Post
#5
|
914 Neferati Group: Members Posts: 5,029 Joined: 31-December 05 From: Pt. Townsend, WA Member No.: 5,344 Region Association: Pacific Northwest |
Have you checked the relay on the relay board? I have not, what should I check it for and which relay is it? The fuel pump relay is on the lower left of the relay board and the main power relay is directly above that. The relays are the same as the headlight relay found under the cover near the headlight motor. If your headlights are working properly, then your relays up there are good. Swap one of those out for the fuel pump relay on the relay board. Hope it works. |
Nogoodwithusernames |
Sep 28 2016, 04:24 PM
Post
#6
|
Member Group: Members Posts: 235 Joined: 31-May 16 From: Nor-Cal Member No.: 20,051 Region Association: None |
Okay so the relays all work, tested all three on the relay board in the headlights.
Weather is hot for this time of year, but only 91F. I wouldn't think that would cause vapor lock. I also tried cranking it over a bit more and I put one of those blue shop rags under the driver side injectors and after maybe 10-15 seconds of cranking the rag had two dime size bits of fuel on it. Seems like it's not enough fuel to me. I've tested the injectors on my Squareback and they put out a fair amount of fuel. Unfortunately I've got no way to check fuel pressure here so anyone have any ideas with this new info in mind? Maybe spark related? |
Nogoodwithusernames |
Sep 28 2016, 06:22 PM
Post
#7
|
Member Group: Members Posts: 235 Joined: 31-May 16 From: Nor-Cal Member No.: 20,051 Region Association: None |
Okay figured it out. Somehow it started running fuel backwards through the loop. So fuel started coming out of the stainless return line that comes into the engine compartment.
(disconnected lines to see if there was fuel flow, and there was! Just not the right way...) How could this have happened because it wasn't running this was previously. I had swapped each line one at a time and triple checked that it was setup the right way. And of course it ran before this. Is the pump running backwards somehow and how would that have happened? |
TheCabinetmaker |
Sep 28 2016, 06:30 PM
Post
#8
|
I drive my car everyday Group: Members Posts: 8,300 Joined: 8-May 03 From: Tulsa, Ok. Member No.: 666 |
More detail. Step by step details about how the fuel ran backwards please. Was this under pressure? Or gravity flow from the return line coming out of the firewall?
|
Nogoodwithusernames |
Sep 28 2016, 08:41 PM
Post
#9
|
Member Group: Members Posts: 235 Joined: 31-May 16 From: Nor-Cal Member No.: 20,051 Region Association: None |
More detail. Step by step details about how the fuel ran backwards please. Was this under pressure? Or gravity flow from the return line coming out of the firewall? Alright, so I had disconnected the return line from the hard line that runs down through the sheetmetal, cycled the key a few times to get flow and the flow came from the hard line which should be the return line from the fuel loop. |
yeahmag |
Sep 28 2016, 11:30 PM
Post
#10
|
Advanced Member Group: Members Posts: 2,421 Joined: 18-April 05 From: Pasadena, CA Member No.: 3,946 Region Association: Southern California |
Did you put a pressure gauge on it yet?
|
Nogoodwithusernames |
Sep 29 2016, 09:29 AM
Post
#11
|
Member Group: Members Posts: 235 Joined: 31-May 16 From: Nor-Cal Member No.: 20,051 Region Association: None |
Did you put a pressure gauge on it yet? No but it was good enough to start it and pull it into the shop at work for the night. I was going to bring my gauge to work with me but forgot this morning. Here's a thought, maybe the line from the pump under the car got kinked so the pump started sending all the fuel to the return line? I'll try to check that today. |
TheCabinetmaker |
Sep 29 2016, 09:45 AM
Post
#12
|
I drive my car everyday Group: Members Posts: 8,300 Joined: 8-May 03 From: Tulsa, Ok. Member No.: 666 |
First. Fuel pumps don't run backwards
Second. Opening the return line at the firewall will gravity drain the tank without the use of the pump. Third. Hoses do not switch themselves and pumps do not feed thru the return line. Forget all this nonsense and do what people are telling you to do. |
Nogoodwithusernames |
Sep 29 2016, 09:54 AM
Post
#13
|
Member Group: Members Posts: 235 Joined: 31-May 16 From: Nor-Cal Member No.: 20,051 Region Association: None |
First. Fuel pumps don't run backwards Second. Opening the return line at the firewall will gravity drain the tank without the use of the pump. Third. Hoses do not switch themselves and pumps do not feed thru the return line. Forget all this nonsense and do what people are telling you to do. Well I don't know what to tell you. It didn't have more than a little fuel left in the lines drip out when I disconnected the line but would squirt out fuel when the pump was on. This is further confirmed by the fact that once I switched the two lines for the fuel loop to the "opposite" hard line, it started right up and ran and was able to pull into the warehouse for the evening. Prior to this it would just crank and crank and not catch. How do pumps not feed through the return line? What is the point of it and all the diagrams showing one inlet and two outlets, one of which is the return line? Are all the diagrams wrong in saying that it is an outlet from the pump? (IMG:style_emoticons/default/WTF.gif) Finally, I have been doing everything that's been suggested so far. Checked the relays, given details, etc. I apologize for not being able to check fuel pressure while it's in the warehouse at work. |
TheCabinetmaker |
Sep 29 2016, 10:02 AM
Post
#14
|
I drive my car everyday Group: Members Posts: 8,300 Joined: 8-May 03 From: Tulsa, Ok. Member No.: 666 |
You just proved my point. The fact that you switched the lines and it ran means the lines were hooked up backwards. They did not switch themselves. Either you switched them, or someone is playing a joke on you.
|
ChrisFoley |
Sep 29 2016, 10:13 AM
Post
#15
|
I am Tangerine Racing Group: Members Posts: 7,909 Joined: 29-January 03 From: Bolton, CT Member No.: 209 Region Association: None |
Okay figured it out. Somehow it started running fuel backwards through the loop. So fuel started coming out of the stainless return line that comes into the engine compartment. (disconnected lines to see if there was fuel flow, and there was! Just not the right way...) How could this have happened because it wasn't running this was previously. I had swapped each line one at a time and triple checked that it was setup the right way. And of course it ran before this. Is the pump running backwards somehow and how would that have happened? With the return hose disconnected in the engine compartment, when you run the pump you will get fuel coming up thru the return hard line, particularly if you have plenty of fuel in the tank. The reason for this is the overflow fitting on the pump which routes excess fuel to the return line thru the tee fitting. The path of least resistance will be the open line. There should also be fuel coming out of the rubber hose from the regulator. Go back and carefully check your fuel circuit. Also check your fuel pressure with a mechanical gauge added to the circuit, usually connected in place of the cold start valve on a 2.0L. The pump may be failing, or have a faulty check valve. |
Nogoodwithusernames |
Sep 29 2016, 10:24 AM
Post
#16
|
Member Group: Members Posts: 235 Joined: 31-May 16 From: Nor-Cal Member No.: 20,051 Region Association: None |
You just proved my point. The fact that you switched the lines and it ran means the lines were hooked up backwards. They did not switch themselves. Either you switched them, or someone is playing a joke on you. Again I did the job last Saturday, one line at a time so as not to switch anything about, and I double and triple checked that everything was connected as it should be. It was running perfectly from Saturday afternoon till yesterday morning. I had taken it out around town, taken it out to a neighboring town 30 minutes away, and got to work 1 hour away before this happened. I don't feel any kinks in the lines under the car BTW. |
Nogoodwithusernames |
Sep 30 2016, 01:00 PM
Post
#17
|
Member Group: Members Posts: 235 Joined: 31-May 16 From: Nor-Cal Member No.: 20,051 Region Association: None |
Okay figured it out. Somehow it started running fuel backwards through the loop. So fuel started coming out of the stainless return line that comes into the engine compartment. (disconnected lines to see if there was fuel flow, and there was! Just not the right way...) How could this have happened because it wasn't running this was previously. I had swapped each line one at a time and triple checked that it was setup the right way. And of course it ran before this. Is the pump running backwards somehow and how would that have happened? With the return hose disconnected in the engine compartment, when you run the pump you will get fuel coming up thru the return hard line, particularly if you have plenty of fuel in the tank. The reason for this is the overflow fitting on the pump which routes excess fuel to the return line thru the tee fitting. The path of least resistance will be the open line. There should also be fuel coming out of the rubber hose from the regulator. Go back and carefully check your fuel circuit. Also check your fuel pressure with a mechanical gauge added to the circuit, usually connected in place of the cold start valve on a 2.0L. The pump may be failing, or have a faulty check valve. Chris, Thanks for the detailed explanation of that. I'll put the fuel loop back the way it should be and check for flow from the pressure/inlet side this time. Of course I forgot my pressure gauge again today (IMG:style_emoticons/default/headbang.gif) maybe I'll pick up a cheap one at lowes after lunch. |
Nogoodwithusernames |
Oct 1 2016, 12:36 PM
Post
#18
|
Member Group: Members Posts: 235 Joined: 31-May 16 From: Nor-Cal Member No.: 20,051 Region Association: None |
Alrighty folks, the jury is in and has decided that the fuel pump has died. There is no flow whatsoever from the feed line even directly at the pump.
|
jcd914 |
Oct 1 2016, 02:23 PM
Post
#19
|
Advanced Member Group: Members Posts: 2,081 Joined: 7-February 08 From: Sacramento, CA Member No.: 8,684 Region Association: Northern California |
I know it is a dumb question but is there fuel in the tank?
When I worked at a shop (almost 20 years) we often had cars towed in because they died or won't start, only to find they were out of gas. When your line came loose did you lose all the fuel? Do you have fuel in the fuel line at the fuel pump? Where your pump is located fuel should flow via gravity to your fuel pump, so you you pull the line off the pump fuel should start flowing out (usually running down your arm and to your arm pit). Jim |
Nogoodwithusernames |
Oct 1 2016, 02:42 PM
Post
#20
|
Member Group: Members Posts: 235 Joined: 31-May 16 From: Nor-Cal Member No.: 20,051 Region Association: None |
I know it is a dumb question but is there fuel in the tank? When I worked at a shop (almost 20 years) we often had cars towed in because they died or won't start, only to find they were out of gas. When your line came loose did you lose all the fuel? Do you have fuel in the fuel line at the fuel pump? Where your pump is located fuel should flow via gravity to your fuel pump, so you you pull the line off the pump fuel should start flowing out (usually running down your arm and to your arm pit). Jim Haha yep there's definitely fuel, I'd be pretty embarrassed if I did that! Got about a half tank and the return line puts out enough pressure to run the engine so I could pull it around into the shop the other day. I'll probably just put in the inline E2000 pump I've got in the garage from my "test stand" to get me by for now. Don't know that I wanna drop $400 on a rebuilt unit from AA. |
Lo-Fi Version | Time is now: 23rd April 2024 - 06:17 AM |
All rights reserved 914World.com © since 2002 |
914World.com is the fastest growing online 914 community! We have it all, classifieds, events, forums, vendors, parts, autocross, racing, technical articles, events calendar, newsletter, restoration, gallery, archives, history and more for your Porsche 914 ... |