Fuel Pressure Build Up

[Bitsyncmaster]

There is a lot of wiring that can make the CSV not fire. My car had 50 ohms in a bulkhead connector going to the CSV circuit. It never fired until I fixed that.

Your best bet is to pull the CSV, put it in a jar and test that it releases a little fuel on cranking a cold engine. If it does you may not have a CSV problem or you have an intermittent problem with it.

[82DMC12]

Do what Dave McKeen says first - pull the CSV out , put in a jar, and turn the key. I would remove the coil wire from the ignition coil first so the car doesn't start trying to run. You just want to see if the CSV is spraying into the jar. If it does, try pinching the female pins in the blue plug closed a bit so they make a better connection. Might just be the plug.

If that still doesn't work and it takes a lot of effort to start after a few days, you might have injectors leaking down at rest. You'll have to pull all the injectors out and try this:

1) Get a medium sized mason jar for each injector. Drill a hole in the lid so the injector fits in just right.
2) Jump the RPM relay and check for injectors dripping into the mason jars. If they are, the CO screw could be too rich. If not, press down on the air flap about 1/3 of the travel and make sure all the injectors start and stop simultaneously. Make sure the spray pattern is a fine mist, atomized fuel, and shaped like an umbrella. When the plate isn't pressed the down, the injectors should not drip. When you are satisfied, while the fuel pump is still running, wipe off the tip of each injector with a non-linting rag so the tip is dry.
3) Dump out the jars and wipe them clean, placing the injectors back into the jars one at a time.
4) remove the pump jumper wire and let the injectors sit in the jars. Check the injectors after 30 minutes and see if any of them are damp. Maybe they even dripped a bit of fuel into the jar. They should be bone-dry if they don't leak down.

If any of the injectors are dripping, I would just replace all of the injectors with a new set of 022 Bosch injectors.

Following this procedure fixed my similar issue (replaced all the injectors after confirming one or two were leaking down over a long period of time).

[Ricker]

Do what Dave McKeen says first - pull the CSV out , put in a jar, and turn the key. I would remove the coil wire from the ignition coil first so the car doesn't start trying to run. You just want to see if the CSV is spraying into the jar. If it does, try pinching the female pins in the blue plug closed a bit so they make a better connection. Might just be the plug.

If that still doesn't work and it takes a lot of effort to start after a few days, you might have injectors leaking down at rest. You'll have to pull all the injectors out and try this:

1) Get a medium sized mason jar for each injector. Drill a hole in the lid so the injector fits in just right.
2) Jump the RPM relay and check for injectors dripping into the mason jars. If they are, the CO screw could be too rich. If not, press down on the air flap about 1/3 of the travel and make sure all the injectors start and stop simultaneously. Make sure the spray pattern is a fine mist, atomized fuel, and shaped like an umbrella. When the plate isn't pressed the down, the injectors should not drip. When you are satisfied, while the fuel pump is still running, wipe off the tip of each injector with a non-linting rag so the tip is dry.
3) Dump out the jars and wipe them clean, placing the injectors back into the jars one at a time.
4) remove the pump jumper wire and let the injectors sit in the jars. Check the injectors after 30 minutes and see if any of them are damp. Maybe they even dripped a bit of fuel into the jar. They should be bone-dry if they don't leak down.

If any of the injectors are dripping, I would just replace all of the injectors with a new set of 022 Bosch injectors.

Following this procedure fixed my similar issue (replaced all the injectors after confirming one or two were leaking down over a long period of time).

Ok. I,let the car sit for a few days. Pulled the CSV and placed it into a jar. Had my wife turn the key and it sprayed immediately in a nice fine mist, umbrella shape. So I don't think it is that or the TTS as it ohmed out Ok. I will try the injectors next as you suggested. Is it possible then, if the injectors can leak, can the CSV leak and do the same thing or just the injectors? Do you replace all injectors or just the one(s) that are bad? I did have them sent out years ago (about 5,000 miles ago) and tested. Said they were all good. Nevertheless, I'll do the testing.

Note: I had the fuel/air ratio adjust a few years ago with a 4 as analyzer and a past '80s dealership DeLorean mechanic.

[82DMC12]

Ok. I,let the car sit for a few days. Pulled the CSV and placed it into a jar. Had my wife turn the key and it sprayed immediately in a nice fine mist, umbrella shape. So I don't think it is that or the TTS as it ohmed out Ok. I will try the injectors next as you suggested. Is it possible then, if the injectors can leak, can the CSV leak and do the same thing or just the injectors? Do you replace all injectors or just the one(s) that are bad? I did have them sent out years ago (about 5,000 miles ago) and tested. Said they were all good. Nevertheless, I'll do the testing.

Note: I had the fuel/air ratio adjust a few years ago with a 4 as analyzer and a past '80s dealership DeLorean mechanic.

Yes the cold start valve could possibly leak down as well but it's uncommon. It's not subject to the same abuse the other injectors are, plus it is solenoid controlled instead of pressure controlled.

Personally, I replaced all six injectors because I had a full unused set handy.

Sent from my Pixel 6a using Tapatalk

[Ricker]

Do what Dave McKeen says first - pull the CSV out , put in a jar, and turn the key. I would remove the coil wire from the ignition coil first so the car doesn't start trying to run. You just want to see if the CSV is spraying into the jar. If it does, try pinching the female pins in the blue plug closed a bit so they make a better connection. Might just be the plug.

If that still doesn't work and it takes a lot of effort to start after a few days, you might have injectors leaking down at rest. You'll have to pull all the injectors out and try this:

1) Get a medium sized mason jar for each injector. Drill a hole in the lid so the injector fits in just right.
2) Jump the RPM relay and check for injectors dripping into the mason jars. If they are, the CO screw could be too rich. If not, press down on the air flap about 1/3 of the travel and make sure all the injectors start and stop simultaneously. Make sure the spray pattern is a fine mist, atomized fuel, and shaped like an umbrella. When the plate isn't pressed the down, the injectors should not drip. When you are satisfied, while the fuel pump is still running, wipe off the tip of each injector with a non-linting rag so the tip is dry.
3) Dump out the jars and wipe them clean, placing the injectors back into the jars one at a time.
4) remove the pump jumper wire and let the injectors sit in the jars. Check the injectors after 30 minutes and see if any of them are damp. Maybe they even dripped a bit of fuel into the jar. They should be bone-dry if they don't leak down.

If any of the injectors are dripping, I would just replace all of the injectors with a new set of 022 Bosch injectors.

Following this procedure fixed my similar issue (replaced all the injectors after confirming one or two were leaking down over a long period of time).

It has taken me some time to do the injector test. What a discovery. One injector had a bad looking spray. Not all did the same amount. Once I cleaned/dried the injector tips and waited about 15 minutes one sprayed, 3 others were wet and one dripped. So, it looks like some new injectors are in my immediate future (along with the clips and rubber seals). Thanks for the direction!

[Timeless]

So, it looks like some new injectors are in my immediate future (along with the clips and rubber seals). Thanks for the direction!

I may have a set for sale. They are new and purchased in 2023 but only used ~30 miles before I decided to go EFI. If you're interested I'll let DPI know to keep them (if they still have them) and when my car returns from DPI I'll gladly send them to you.

[Ricker]

I may have a set for sale. They are new and purchased in 2023 but only used ~30 miles before I decided to go EFI. If you're interested I'll let DPI know to keep them (if they still have them) and when my car returns from DPI I'll gladly send them to you.

Sorry, I already ordered them from Deloreango.com yesterday and they have already shipped (got the notice this morning).

[Timeless]

Sorry, I already ordered them from Deloreango.com yesterday and they have already shipped (got the notice this morning).

All good!

[Ricker]

Well I got the new fuel injectors from Deloreango and installed them this morning. Car started up right away and ran very nice and smooth. Let it run for a while at idle but it the idle did increase (which has been typical went in park). Turned it off. Went out 20 minutes later and nothing. Won't start or even fire. I touched nothing else. It ran, I turned it off, and now nothing. I let it sit for a while to cool off and still nothing. Any ideas? What could I have done. The fuel pump is running.

[Bitsyncmaster]

Any change to components in the fuel system would require the need to check mixture via dwell.