ElRicardo

‘87 Turbo. Car starts and runs fine with DME relay jumpered. However when DME relay inserted (we have tried several) the car will sometimes start and then die (classic fuel starvation) at random intervals and will not refire until the jumper is put back in place. If only one relay exhibited this issue I’d say bad relay, however this occurs with other DME relays inserted. Thoughts?

Tiger03447

Perhaps if you pulled the relay out and sprayed contact cleaner into the socket that might help. Otherwise it’s power probe time. That will tell you if the lead to the ground is OK as well as the power lead to the pump. If I remember correctly, one side of the pump is grounded and the other side powered. There may be a bad ground wire from the relay up to the grounding point up under the dash… left hand side..way up close to the firewall and under the windshield on early cars. Don’t know about later ones. Is this circuit grounded through the DME? Or, perhaps a loose connection at the pump? Or corrosion on the lead going from the fuse block to the relay,? When you jumper the socket, you are getting a great connection and current flow. When a relay is in place, you get enough to sometimes run the pump, but not enough to bridge corrosion or a partially broken wire or a loose connector somewhere. Just some thoughts. Hope this helps some😀

walfreyydo

Analog relays, even multiple, can be bad especially if they are used. I highly suspect it is the DME relay based on your description, so I would suggest a soild state relay instead of the old analog ones, just to eliminate that as a possibility. F9Tech has them