Cranks but no start troubleshooting

[Indymarco]

Hello fellow fuel injection spider owners. Looking for some help. Started troubleshooting why my 81 Spider 2000 was taking long time to start when cold (hot start good). Found cold start valve was not operating/ no voltage at terminal during crank first start in morning ie engine cold. But it would finally start and ran/drove just fine. Now engine cranks but will not start. Following Fiat fuel injection diagnosis technician manual step by step. Have good spark at plug so ignitions fine. Fuel pressure at manifold during crank is 35 psi so pumps ok. However at step 4 check voltage at injector no test light during crank. Jumped to step 11 per manual. Went down the double relay and ECU tests step 11 through 19 Only problem found was step 12 - voltage input to fuel pump relay of relay set.. With the ignition off I got test light on when I put pins on terminals 88y and 85. Don't think that's supposed to happen. Thoughts?

[wizard124]

My thoughts:
1) If you have voltage readings to the relay with the ignition "Off" , I would start troubleshooting there. Ignition switch terminal 15 should read zero voltage with the switch in Off. If there is voltage, either the contact is bent or fused; or someone has spliced or modified the wiring around a faulty ignition switch.

2) You stated the CSV isn't working as there is no voltage at the plug. This indicates a faulty thermo time switch or bad wiring as this "Start Signal" comes from ignition switch terminal 50 (the "crank" position of the switch).
This "Start Signal" also runs into the ECU and the injectors start to operate.

Remember this is a double relay. Obviously, the fuel pump relay is working and you have proper fuel pressure. The other relay energizes the ECU and injectors.

Easiest to swap out the double relay with a known good one, but they are $$$$

[spider2081]

With the ignition off I got test light on when I put pins on terminals 88y and 85. Don't think that's supposed to happen. Thoughts?

Looking at the wire diagram for the fuel Injection:
Pin 88y of the dual relay is "hot all the time" power through an inline fuse.
I think Pin 85 of the dual relay has a ground on it when the ECU is plugged in.
If you unplug the ECU does the test light still light when connected between pins 85 and 88y?

[Indymarco]

Thanks to both of you for the responses. Very helpful. I'll check out the ECU grounding when disconnected question. I already have another thermal time switch to replace the old one. They're not easy to get to. Also found a thread under Electrical Issues entitled Fuel Injection Relay that contained slot of detailed info on how the double relay set works and an article on Miraforia entitled Double Relay bench testing and repair. I'm going to make the test cables described in that article and test my double relay functionality. At least then I'll know if it's the relay set or if I need to look elsewhere for the problem. I'll let you know the results.