PSI Conversion

[cpd004]

Originally Posted by Swain

Hooked up a NOID light this AM. The light comes on then never comes back. Seems like the injectors only get a signal for a second then goes away. I have sent the ECU back twice. I have a guy coming over Sunday to hook it all up.



We have added grounds everywhere. Cleaned off metal so its a good contact.

My Ls3 does this. When I initially turn the key to run, the noid light flashes for like a 1/2 second. At crank it doesn't flash, but when the motor fires, it begins to flash constantly. I have no starting issues and am running an E38 with Corvette regulator (return less).

[Vega$69]

Originally Posted by cpd004

Corvette regulator (return less).

Corvette reg does have return to tank at the regulator.

[cpd004]

Originally Posted by Vega$69

Corvette reg does have return to tank at the regulator.

I meant returnless at the rail...thanks!

[Vega$69]

Originally Posted by cpd004

I meant returnless at the rail...thanks!

Yep. Much better way then to return fuel from the rails that has been heated as it passes through the engine bay.

[badazz81z28]

I know I'm super late to this party, but I don't have my wires for the TCC pedal hooked up either. Runs just fine. Like mentioned, the #1 reason for not firing is the constant power to the ECM while cranking.

I ran my ECM power from the HEI power wire.

[ItDoRun]

Originally Posted by Vega$69

You don't need any additional relays or diodes.

I've done 5 LS swaps on 1st Gens all with factory ign switches. 3 GM Perf Harness, 1 Psi and 1 reworked GM take out harness.

LS ECM

You need 12v switched power to the PSI fuse box.

The ECM is powered up with ign 12v. When you turn the key on the ignition and fuel pump relays close.

When you hit start the purple wire provides 12v to the starter.

From PSI

NO-START
1. Red Ignition Wire (From back of Fuse/Relay Center) has 12-volts with the Key in the ON
position and CRANKING position. This cannot be stressed enough, most NO-START
conditions can be traced to this wiring issue.
2. Check that 2 Large Ring Terminals by Crank Sensor are connected to CONSTANT POWER.

Batt. Battery Positive (2 LARGE RING TERMINALS COVERED IN BLACK HEAT
SHRINK), These are often mistaken for ground wires because of the black heat shrink

You hit the nail on the head here! I just started mine for the first time this evening. Got everything wired up (harness and ECM from PSI as well). Wasn't getting juice to the fuel pump wire (87 slot on relay). Come to find out I had tied those two Battery Positive wires to the block as grounds not to the starter as required. Car starts and runs now but won't idle. Not hijacking this thread so I'll start my own but am subscribed to this one.

[cjsgarage]

That stinking starter lug wire. One of the reasons I don't like the PSI harness.

[ItDoRun]

Originally Posted by cjsgarage

That stinking starter lug wire. One of the reasons I don't like the PSI harness.

It would help if the wire was red! HOWEVER.....my fault for not reading the instructions clearly.