Speed density wiring issue (solved)
03-13-2017, 12:55 PM
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Car: '90 Trans Am-12.45@110.71
Engine: 355 w/AFR 195's Elem. 400/430 HP/TQ
Transmission: Tremec T-56
Axle/Gears: 12 Bolt 3.73
Speed density wiring issue (solved)
I am going to throw this out there in case anyone else has had the problem.
I am working on a '91 SD harness. (730 ECM)
The problem..... the ECM does not turn on the primary fan.
The temp control is set at 190* even at 220* the fan does not turn on.
I ground the wire at the "E" 8 terminal on the ECM connector and the fan comes on but the ECM won't turn it on. (so the relay is good)
I have checked all the grounds at the ECM connectors that connect at the back of the heads and they are all good.
Also, the 02 sensor reading is not right and when I open the throttle the engine pops and bangs. It runs ok at idle and 3000 rpms
I must be missing something somewhere.
Any help?
Thanks
I am working on a '91 SD harness. (730 ECM)
The problem..... the ECM does not turn on the primary fan.
The temp control is set at 190* even at 220* the fan does not turn on.
I ground the wire at the "E" 8 terminal on the ECM connector and the fan comes on but the ECM won't turn it on. (so the relay is good)
I have checked all the grounds at the ECM connectors that connect at the back of the heads and they are all good.
Also, the 02 sensor reading is not right and when I open the throttle the engine pops and bangs. It runs ok at idle and 3000 rpms
I must be missing something somewhere.
Any help?
Thanks
Last edited by Dyno Don; 03-14-2017 at 04:13 PM. Reason: correction
03-13-2017, 01:10 PM
#3
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Car: '90 Trans Am-12.45@110.71
Engine: 355 w/AFR 195's Elem. 400/430 HP/TQ
Transmission: Tremec T-56
Axle/Gears: 12 Bolt 3.73
Re: Speed density wiring issue
Normally open
I have tried several known good ecm's, no change
I have tried several known good ecm's, no change
03-14-2017, 04:15 PM
#5
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Car: '90 Trans Am-12.45@110.71
Engine: 355 w/AFR 195's Elem. 400/430 HP/TQ
Transmission: Tremec T-56
Axle/Gears: 12 Bolt 3.73
Re: Speed density wiring issue (solved)
Yes, it was good. (E 15)
N.O. fan fixed that fan issue
The pickup coil in the dizzy was bad
N.O. fan fixed that fan issue
The pickup coil in the dizzy was bad