E21,E2 ECU connector ground locations

ThunderBolt
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Posts: 18
Joined: Mon Sep 16, 2019 11:40 am

E21,E2 ECU connector ground locations

Postby ThunderBolt » Tue Sep 17, 2019 8:14 pm

I bought a 1985 corolla gts smallport swap with wiring issues. I verified 40 psi at the fuel rail and 12v to the injectors with all four of them disconnected. I am getting spark, but my car won't start... after reading a whole lot Im guessing its a ground issue or the ECU is bad. I have checked continuity between the 3 ecu connectors and the known end points from the wiring diagram. So far I have verified grounds at (E01,E02,E1,SPD,BATT,W,STA). I believe E21,E2 are joined together on the same ground wires?? I did verify grounds on the E21 circuit to the AFM,TPS,THA but I could not find the engine cylinder head earth point. Where are the ground points to E21,E2 ? please help me club4ag

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jondee86
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Re: E21,E2 ECU connector ground locations

Postby jondee86 » Thu Sep 19, 2019 2:49 am

E21 and E2 are sensor grounds and the ground path is via the ECU. The ECU
ground points are three (usually brown) wires that are all connected to a single
brass ring connector that is secured to the top rear of the intake manifold by
one of the bolts that holds down the heavy wiring trunk that runns along the
injector side of the head.

There should be a ground strap from the rear engine hook bolt to a bolt on
the firewall. A heavy ground strap from beside the starter to the chassis and
one from the transmission to the chassis. There is also a black wire with a
single pin plug that comes from I dunno where and ends at the chassis near
the starter. Pretty sure if that is not connected the engine won't run.

Cheers... jondee86
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persists in trying to adapt the world to himself. Therefore, all progress
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ThunderBolt
Club4AG Regular
Posts: 18
Joined: Mon Sep 16, 2019 11:40 am

Re: E21,E2 ECU connector ground locations

Postby ThunderBolt » Thu Sep 19, 2019 9:35 am

I will double check all those suggestions.