IntercooledC6

iTrader: (2)

Well, I am stumped. This engine is a 5.7 ls1, ecm is a 2000 I haven't any idea where the harness came from but it apears to be A/M. It came with the block. The engine is rebuilt with mti x1 cam. The base tune was done by frost tunning. I found out that my bank 1 bank 2 wires were crossed when the harness was made. Bank 1 sensor 1 should be pur/wht, tan /wht. On the harness the bank 2 had the bank 1 wires. Pur/wht, tan/wht.

I switched them to the right pin outs at the ecm. Bank 2, o2 is working corectly M.v start at 450 and come down when the key is turned on. Bank 1 o2 stays at 450 m.v . Like it isn't connected. The o2 heater circut is working and gets hot on bank 1. I back probed the wires on bank 1, they are showing a complete circut. Red and blk wire on harness to bank 1 plug shows 12 volts and ground.

What am I missing. Sensors are new. I checked bank 1 o2 sensor and it does move between 0 and .5...

This engine is in a 68 camaro. Long tube headers. I know o2's don't last to long in long tubes. At leastthats what I have read.


Btw I am using hp tunners software.

Any help would be appreciated.

Larry

IntercooledC6

iTrader: (2)

Update

Even though I tested the wires with a multi meter and wires showed good, the pin on the end of the wire was not making contact with the ecu. It was seated correctly. I found this out by running new jumper wire across to the ecm and when i pressed on the wire to probe it, it would connect properly. I have no explanation why this happened to that pin. Maybe when I switched the wires from bank to bank?

I had a simular problem with my TPS sensor connector. Once I replaced it, Then it worked fine.
I Hope this helps somebody out in the future. This little issue cost me about $120 on buying new sensors ect... when it was a wiring issue all along Lol...

Mike454SS

iTrader: (4)

I've seen pins do that in fuse panels under dashboards before...can't find a wire continuity problem, no blown fuse...and something that just doesn't turn on (like a radio, or dash lighting). Glad you got it fixed, sorry I didn't see your post before you were spending money on sensors...but at least you have spares now, and piece of mind that you've got fresh sensors running the engine.

IntercooledC6

iTrader: (2)

Thanks mike, That little problem had me going. I even switched ecm's thinking
it was the problem. I could have ruined my new engine when I first started it up do to the
Banks 1 and 2 wires being switched. It was just dumping fuel down the cylnders lol.

That harness was on a engine that had thrown a rod out the side of the block.
Go figure lol. It would never run correctly with banks 1 and 2 o2 wires switched.

I have learned alot thru this build.

Long live LS1Tech.com

poss

I know, old thread, but I had a very similar problem I've been troubleshooting all day. Turns out the heater pin wasn't seated all the way in the connector. Thanks for the follow up post IntercooledC6!

IntercooledC6

iTrader: (2)

I glad you got it straighten out.

That type of issue can be very expensive and very frustrating
Don't ask me how I know lol.