Starting problem after replacing fuel lines

[Stainless]

After all the recent fire scares, I decided to replace my original fuel lines. While it was more time consuming than I anticipated, and after I fixed all the leaks, I was surprised that the car struggled to start. When I first started it after replacing the lines, it ran extremely rough for about a minute, then it smoothed right out and I thought everything was going to be fine and dandy. Not so.

I don't drive my car much, but prior to replacing the lines, it would fire up right away with zero problems. I replaced the thermotime sensor a couple of years back to fix a cold start issue I was having when it was winter time. Until now, that is the only starting problem I've ever had. Now when I go to start it, it fires up right away, just like it used to, but doesn't stay running. It dies after 1 second, even if I give it gas. It will then crank and crank and crank and crank until the battery starts to die.

Today I hooked hooked the DeLorean up to my Corolla to give it more juice so the battery wouldn't die and I got the DeLorean started. It acted like it was going to fire right up, but then died. Then it cranked and cranked and cranked and it finally fired up again, but ran really rough. I could only keep it going by giving it a lot of gas. After about it minute, I let it idle and it didn't die, but didn't run very smooth. After another minute or so, it started to idle out nice and smooth. I drove it for about an hour tonight and it ran flawlessly. I took some neighbor kid for a drive and it felt like everything was normal. It ran like a top.

After coming home, I shut it off, and then tried starting it again. It fired up great and ran smooth right away. Of all the threads I've read about replacing fuel lines, I've never come across the new lines creating a starting issue. All the lines look fine except the one going to the cold start valve. It's kind of twisted. I felt like that was the only option I had to get it to line up correctly. I don't know if that line is kinked, causing the starting problem, or if I did something else wrong. Any help is appreciated.
2016-07-02 16.24.55.jpg

[Bitsyncmaster]

You probably knocked a vacuum line off somewhere. Also check that connector on the timing advance solenoid.

[jmettee]

Or you have a couple lines swapped. Post a pic of the right side of your fuel distributor & the frequency valve (all in 1 pic so we can verify the routing)

[Jonathan]

+1 on a routing mistake. Double check that the ignition wires are correct as well as the fuel and vacuum lines.

[OverlandMan]

Agree with others already posted. Vacuum line off or incorrectly routed and/or fuel line incorrectly routed. Sounds like something on the open-loop side of the system, when the car is cold. Maybe start there (CPR, WUR, FV... that stuff). Also make sure the return lines are ordered correctly where they connect to the fuel dist. I've heard if this is incorrect it will cause problems. This is the 17mm bolt (I think) where the 2 connections stack on top of each other.

See my pic below. The outside loop goes to the FV while the inside goes to the metal return line (back to the tank) under the ignition coil and bulkhead.

FuelSystem_2015_03XX.jpg

[Stainless]

I'll see if I can snap some better pictures tonight. I'd be surprised if I got a line in the wrong place as I replaced only one line at a time, but it's possible. Here's the only pic I could find on my camera that has a different angle. Let me know if you see anything unusual. More to come.
2016-05-16 21.58.57.jpg

[StanMan PushN 88]

Agree with others already posted. Vacuum line off or incorrectly routed and/or fuel line incorrectly routed. Sounds like something on the open-loop side of the system, when the car is cold. Maybe start there (CPR, WUR, FV... that stuff). Also make sure the return lines are ordered correctly where they connect to the fuel dist. I've heard if this is incorrect it will cause problems. This is the 17mm bolt (I think) where the 2 connections stack on top of each other.

See my pic below. The outside loop goes to the FV while the inside goes to the metal return line (back to the tank) under the ignition coil and bulkhead.

FuelSystem_2015_03XX.jpg

Questions:
Great shot of your fuel lines OverlandMan! For some of us considering swapping out, what are the acronyms CPR, WUR, FV? Also, where did you get the fuel lines, are you happy with them? Other suggestions? (I've still got rubber lines but I think previous owner replaced in 2012).

StanPushN88

[Jonathan]

Jared,

What's your car doing right now? Starting and idling that is? The last line from your first post said it struggled right after replacing the lines, then ran rough a time afterwards, then ran like a top when you gave the neighbor kid a ride. Plus it restarted no problem right after getting home.

I don't know what would be "typical" but the car struggling for a little while soon after replacing all your fuel lines wouldn't be all that unexpected since, at least initially, you are trying to start an engine using fuel lines that are all empty. Add to that some leaks that got fixed, and what you first described might just have been you getting all the fuel lines completely full and your engine finally running well because of it.

I didn't see anything out of the ordinary in your last few pictures. I would keep trying it and going for those short drives and report back whether it is fine or is still having troubles.

EDIT: here's part of an acronym list too http://dmctalk.org/showthread.php?17...n-Acronym-List

[Stainless]

It did initially struggle to run when first replacing the lines. What now is happening is that it struggles to start each and every time after it sits for a day or more. It cranks, cranks, cranks, but doesn't fire up for the longest time. I'm talking minutes, not seconds. So much cranking that the battery will die, which results it me having to jump it. It will initially run rough for a minute or so, then it smooths out and all appears to be fine until the next time it sits for a couple of days. Then this process repeats.

Again, it never had any starting issues prior to replacing the lines, the only exception being the issue several years ago with cold starting, which required a simple thermotime switch replacement. I'll take a look at the big bolt on the WUR. What else can I check? Is it potentially a fuel pressure issue? Could one of the lines be seeping pressure which could cause starting issues? I'm grasping at straws as I am clueless.

[Jonathan]

What came to mind isn't too far off what you said with it possibly "seeping pressure." I got thinking of it like how a sump pump can struggle to get itself primed if the check valve or other means of supplying suction head isn't working.

In our fuel systems, that would mean the fuel pump is losing prime and the fuel on the suction side of the pump is falling back into the tank.

Did you do any work within the fuel tank or on the pump?

It sounds like you didn't and just stuck to the lines back at the engine, so I might guess that over the course of replacing the lines, some grit or debris got loose or somehow introduced into the system and maybe it's plugging up the filter screen on the pump now.

At this point, I might carefully inspect the inside of the fuel tank and find out what is going on in there. You don't need to take everything out, empty it and clean it right yet, but perhaps loosen the fuel pump boot clamp and gently lift up the pump to allow you to see what the suction assembly looks like. This may not turn out to be your problem, or it could be and it isn't that difficult to have a good look in there and at least rule it out if it all looks fine.

EDIT: also, how much gas is in the tank right now? It might be almost empty and that's adding to the problem. If there's filth in there, it should be cleaned out. But adding more fuel to sort of dilute the debris a little could keep it away from the suction tube. Sounds like you might be sucking the same debris back into the pump each time yet once it's running, it stays clear until shut off and things settle again.