Delorean won't start

[Gumby]

Hi my 81 delorean has a prob no start. It has a rebuilt fuel distributor the air box has been re-sealed no vacuum leaks
Have pulled the injectors pulled the rpm relay and shorted brown/purple white wire to run fuel pump the spray pattern is great. adjusted spray perfectly. When I re-installed the rpm relay and replaced the injectors nothing no gas getting to the intakes as the plugs are bone dry.. have swapped rpm relays same problem.

Question. There is a pulse received from the distributor to activate the rpm relay for the fuel pump is there a way to check using ohm meter to see if a signal is getting to the rpm relay or can I dump a bunch of fuel into the cylinders by shorting the relay brown/purple wires to have it run continually to check if is a fuel issue?

P.s. checked spark coil beautiful fat blue spark...to plugs.... Hmmmm..

So many questions so little time..
Thx gumby.

[Bitsyncmaster]

Was it running before you replaced the FD? Did it just die overnight without any parts changing?

[Jonathan]

You seem to have already covered much of the obvious stuff.

Can you elaborate on what you meant by or how it is you resealed the air box? Where or what portions and with what type of sealant?

I ask only because maybe the problem isn't something very obvious and could have been overlooked. Your description sounds like you have fuel and spark for the most part so I got wondering about the air piece.

[DMCMW Dave]

Hi my 81 delorean has a prob no start. It has a rebuilt fuel distributor the air box has been re-sealed no vacuum leaks
Have pulled the injectors pulled the rpm relay and shorted brown/purple white wire to run fuel pump the spray pattern is great. adjusted spray perfectly. When I re-installed the rpm relay and replaced the injectors nothing no gas getting to the intakes as the plugs are bone dry.. have swapped rpm relays same problem.

Question. There is a pulse received from the distributor to activate the rpm relay for the fuel pump is there a way to check using ohm meter to see if a signal is getting to the rpm relay or can I dump a bunch of fuel into the cylinders by shorting the relay brown/purple wires to have it run continually to check if is a fuel issue?

P.s. checked spark coil beautiful fat blue spark...to plugs.... Hmmmm..

So many questions so little time..
Thx gumby.

How do you know there are no vacuum leaks if it won't run?
No
Yes

[Gumby]

The air box plate is very hard to push down when cranking no (vacuum leaks) the injectors fire strong when in jars for flow control and rpm relay removed and fuel pump bussed to 12volts. when relay re-installed and injectors put back Spark plugs dry tried 2 different rpm relays.
Question does the rpm relay receive a signal from the distributor to forward info to the rpm relay to begin pulsing?
Have worked on many cars motorcycles etc. but this has me a bit stumped
Can I check,the distributor pulse coil for resistance without removing the intake etc?

[Bitsyncmaster]

The signal from the ignition distributor drives the ignition ECU. The coil voltage (pulses) then drive the RPM relay, idle ECU and Tach.

[DMCMW Dave]

If you are getting spark the distributor pickup and ECU are working. You can also verify this when cranking- does the tach move?

You can jump the RPM relay (brown to white/purple AND yellow/red) and make the pump/FI control run. If it won't run like that you have other issues. Dry plugs is not enough of an indication, as the fuel distributor may be way out of adjustment and no fuel will flow when cranking.

I don't really know why but I've found that a freshly rebuild fuel distributor will almost always be way too lean, often too lean to run the car. It should start on the cold start injection and then die. At least once. Although in warm weather one try may be enough to time out the thermotime switch for hours.

You may be chasing a second problem - does the cold start valve open/spray when you first crank the car?

When you installed the fuel distributor did you adjust anything?

[Gumby]

Hi yes the tach goes too about 500 rpm when cranking I did adjust the fuel distributor made it rich ( have also tried lean) is that the brown to yellow red? The wireing and what is fi control?.. So brown 12volts to yellow red? What should that override??

[DMCMW Dave]

Hi yes the tach goes too about 500 rpm when cranking I did adjust the fuel distributor made it rich ( have also tried lean) is that the brown to yellow red? The wireing and what is fi control?.. So brown 12volts to yellow red? What should that override??

That will turn on the fuel injection (Lambda) computer and you should hear the frequency valve buzz. White/purple is the fuel pump. Brown is B+

[Gumby]

Hi the reply is only adding half of my response the rest is not coming thru.