HELP: D won't start without starter fluid

[bfloyd]

When it starts using starter fluid... how long does it stay running?

2 years ago when I rebuilt my car, I too replaced the fuel pump with the new DMCH fuel pump / fuel sender combo unit. I could get the engine to start with starter fluid, but as soon as the starter fluid burned off it died. In my haste to get the car running, I accidentally installed the check valve in the fuel line at the pump backwards. With the check valve backwards, it wouldn't let gas get past the valve. Once I reversed it, it worked. It did run rough at first, but a little trial and error with the 3mm allen wrench in the air metering box fixed that right up.

Check your fuel connections carefully, and verify that the check valve is installed in the correct orientation.

[FireProofCane]

Try disconnecting and reconnecting the plug to the frequency valve a couple of times. Sometimes a little corrosion is all it takes to keep it from working. If the frequency valve is not working the motor would run too lean. If there is no plug over the mixture screw the motor would run too lean. The combination would be so bad the motor won't run at idle. You probably also have other vacuum leaks making it even leaner. You also have all of the usual stale fuel system problems like:
Stuck fuel plunger
Plugged up/dirty/bad spray pattern injectors
Old, hard, leaky injector seals
Probably a bad CPR so it runs badly til it warms up.
Point is you have to go over the whole fuel system to get the motor to run well, not one thing at a time. The best place to start is the fuel tank. Empty it and wipe it out with Acetone. Reassemble the fuel pump and then replace the fuel filter.

Thank you, this is good info on the car running lean. When I get a second hand over to help me with the car I will check to see if the frequency valve is running. Then tackle those other potential issues.

[FireProofCane]

Here's a couple more electrical things to double check:

You can see both of these two items in your 5th picture.

The first is the pair of connectors that are used with the full throttle switches. Your car appears to be a manual transmission, so you only need one of them connected. The one that should be connected (I'm talking on the car's wiring harness side) on a manual trans car is the one with the pair of wires which is black for the ground wire and light green for the other wire. The connector you DON'T use on a manual trans car is the pair with the LGG wire (which means light green/green). This wire is for the automatic trans kickdown mode. They will look similar until you see them side by side. Basically the one you don't want has two shades of green (striped) and the one you do want to use is a solid green. Could be that someone plugged the wrong connector in for you (it is those white connectors that look like Tetris puzzle pieces).

The other thing to check on is the ground wire for the O2 sensor. You can see it in the area of the frequency valve and it is a red wire. It has a quick connect on it. The one end is screwed down and into the block and the other end uses that quick connector to attach to what goes to the O2 sensor and becomes the ground reference. I've attached a picture from my own car where you can see a red arrow indicating where it is supposed to be fastened to (mine is attached slightly above as the intended threaded hole was no good). Don't tug too hard on the connector end, but make sure it is still plugged in.

Attachment 52369

Thank you, I'll check on the connectors tonight.

[FireProofCane]

When it starts using starter fluid... how long does it stay running?

2 years ago when I rebuilt my car, I too replaced the fuel pump with the new DMCH fuel pump / fuel sender combo unit. I could get the engine to start with starter fluid, but as soon as the starter fluid burned off it died. In my haste to get the car running, I accidentally installed the check valve in the fuel line at the pump backwards. With the check valve backwards, it wouldn't let gas get past the valve. Once I reversed it, it worked. It did run rough at first, but a little trial and error with the 3mm allen wrench in the air metering box fixed that right up.

Check your fuel connections carefully, and verify that the check valve is installed in the correct orientation.

As long as I keep my foot on the gas, the car will stay running above 3k RPM's for as long as I want. As soon as I let my foot off the gas, it dies.

[Jonathan]

As long as I keep my foot on the gas, the car will stay running above 3k RPM's for as long as I want. As soon as I let my foot off the gas, it dies.

Generally speaking, this tells us the idle system is not taking over when it should. For one reason or another, when you aren't holding the throttle manually, the engine stops getting fuel, air or spark... or any or all of those three in combination.

[opethmike]

Shot in the dark here, but WAY back when I still had K-Jet I had a similar issue; the car would only start and run if I held the throttle open (right around 3,000 RPM). Turned out that the piping from the idle speed motor into the mixture unit had come out of the mixture unit.

To check for that:

Take the air filter housing off of the mixture unit
Close the garage door so it is dark in the garage
Shine a flashlight at where the copper pipe from the idle speed motor goes into the mixture unit body
Gently (GENTLY!) press down on the mixture unit plate, and look for the light of the flashlight shining in

If you can see the light, then the pipe or its o-ring & seal has come unseated.

[lazabby]

Here's a couple more electrical things to double check:

The other thing to check on is the ground wire for the O2 sensor. You can see it in the area of the frequency valve and it is a red wire. It has a quick connect on it. The one end is screwed down and into the block and the other end uses that quick connector to attach to what goes to the O2 sensor and becomes the ground reference. I've attached a picture from my own car where you can see a red arrow indicating where it is supposed to be fastened to (mine is attached slightly above as the intended threaded hole was no good). Don't tug too hard on the connector end, but make sure it is still plugged in.

Attachment 52369

Where is the red wire located that is a ground for the O2 sensor. I was with another Delorean owner a few days ago and noticed that there were no wires connected to the right hand side. He couldn't remember what was suppose to be grounded there but was pretty sure there should be something. Perhaps it's the O2 sensor. I don't recall seeing any loose wired in the back of the engine that are red.

[Jonathan]

Where is the red wire located that is a ground for the O2 sensor. I was with another Delorean owner a few days ago and noticed that there were no wires connected to the right hand side. He couldn't remember what was suppose to be grounded there but was pretty sure there should be something. Perhaps it's the O2 sensor. I don't recall seeing any loose wired in the back of the engine that are red.

It is the red wire just above my red arrow (in the photo I attached). I had put that red arrow where it is to show where that ground is supposed to be screwed into the block. I moved mine a little away because I had a snapped off screw chunk in the proper hole. It is really just about two or three inches of that ground wire that has the red wrap on it. It has one of those typical black quick connects on it that then plugs into an opposed end that eventually leads to the ECU box connector behind the driver's seat. I don't have the drawings in front of me at the moment to look up the specifics though...

[FireProofCane]

Just wanted to thank everyone for their help. I'm not letting this thread die but I'm out of town on vacation for a week. I will be getting my hands dirty again when I get back and I'll let you all know what I find. Thanks again!