All hard parts have been changed, grounds in the engine bay checked.. only thing left is the harness itself ??
Bought, wrecked, rebuilding a 2009 LMM
- Thread starter malibu795
- Start date
Is it a grounding issue? I did some research when I had to fix that other Silverado and apparently where they tie the grounds together at the splice joints, it's just twisted wire. and this is has been the main issue. No solder to keep it from unraveling.All hard parts have been changed, grounds in the engine bay checked.. only thing left is the harness itself ??
I admit, I was sick of it after spending 10 hours trying to figure it out on that truck. Everything checked out good, until you drove it. a few minutes down the road it would go REP and then repeat even after clearing it. I was thinking maybe the TAC module board was going bad or had a cold solder joint. I purchased a pedal, harness, and the module. I happen to have a known good TB and I swapped every part on that truck and it only started getting worse. I didn't want to tear the harness apart looking for the ground splice joint so I ran a redundant ground directly from the battery to the TAC module and problem solved. I ended up using a T-Tap and running the wire around the fuse box, Then used a side post adapter and attached it with an eyelet to the post.
If it was in nicer shape and the owner actually cared for the truck, I would have spent the time to go through the harness. They just wanted it fixed as it's his only transportation and he is not in a position to buy something new. And the work I did is still way nicer than the work from the previous shop where all the problems started....
Pretty much deducted it's somewhere in the harness underneath the loom.. the CMP, I think, is a 12v reference problem. Can't remember it off hand.
Codes on my suburban are.
P0342 cam position A circuit low... rough understand is circuit #633
P0102 MAF A circuit low, rough understanding is circuit #552
Need to dig up pin out diagram for the ECM.. but don't have adapters yet to pin the connectors to check for continuity etc
P0342 cam position A circuit low... rough understand is circuit #633
P0102 MAF A circuit low, rough understanding is circuit #552
Need to dig up pin out diagram for the ECM.. but don't have adapters yet to pin the connectors to check for continuity etc
Attachments
My 408 thru those codes when my battery was low and I was starting it.
I've got 2 group 78 800cca batteries with 2ga positive cable and 2ga ground to block on the PS battery to the DS.
Thought about replacing the cable from battery to fuse box.. have clean the junctions, though issues still remain
I haven't checked voltage accuracy while cranking of the dash gauge. it will drop around 10V on the dash
Cranking wise, it spins roughly as fast at -30°F as it does at 70°F with 10W40 oil.
I can clear the codes after start up and they don't come back but will show pending...
doesn't explain random engine cut out going down the road
Play with the Key cylinder yet?
On that 03 harness, I wonder if you can just swap the ECU connectors and repin it to work for the 01. The 01 should be Red and Blue Vs. the 03 Green and Blue
The only major thing I can think of that would be different is the 2001 would have a 1 wire oil pressure sensor Vs the 3 wire sensor used on the 03 up.
Being a 6.0L it should have still had the cable TB so it should have separate IAC and TPS plugs Vs the Electronic version.
The 02 Sensors Plugs might be different but I am not sure.
I am not sure if any of the pins moved on the Fuse box plug either.
The only major thing I can think of that would be different is the 2001 would have a 1 wire oil pressure sensor Vs the 3 wire sensor used on the 03 up.
Being a 6.0L it should have still had the cable TB so it should have separate IAC and TPS plugs Vs the Electronic version.
The 02 Sensors Plugs might be different but I am not sure.
I am not sure if any of the pins moved on the Fuse box plug either.
Yeah, no change, though can pull key out while running ??
Maybe the starter is bad or has poor connection.
I had a neighbor with this issue on an 07 and the MF that worked on that didn't tighten the positive battery cable. Occasionally when he would go over a bump it would completely die. Was random too.Yeah, no change, though can pull key out while running ??
I found Nordstroms Automotive in South Dakota has a similar engine harness to yours. 02 2500 6.0/Auto 4x4 . link below just in case.
Then I found an 02 1500 harness that I couldn't pass up for less than $75 shipped to me... could maybe modify it. I know there is a few pins that are swapped around on the 4L80E Vs. the 4L60E plus it needs the a 2nd VSS plug and wiring added.
I guess I should also ask, is the ECU stock? or has it been tuned?
Starter was replaced in Jan 2019.. I have no issues cranking, getting it to fire is different story and usually involves few cycles of the key along with few backfire out the exhaust.
Check MAF
I have 4.8V on B/#472
I have battery voltage D/#239 and checking ground C/#451
Looks like you need to check continuity on #432 and #633 to the ECM. If all is good then sensor(s) or possibly PCM
Nice!
Yeah ECM is tuned with EFI live.. I pulled all the TQ management out of it, and remapped trans shift points, adjusted speedo, shortly after I got it on the road in '16. Haven't changed it since.
My arms and leads aren't long enough to go from one side of the truck to the other. For any of the ends on the PCM connectors.
?
Don't have time to dig to the cam sensor tonight.
If you suspect the ECU LMk. I have a stream for those.
Have these enroute should be here Saturday.. some time.
20' leads should allow me to stretch some distance ??
20' leads should allow me to stretch some distance ??
The multimeter stuff showed up about 5pm this evening.
bought 10' of 2ga and 5' of 4ga cable and some 1/4", 5/16", 3/8" eyelets for both cables.
Remade the battery to fuse box cable along with alternator to battery cable. Haven't done the starter cable yet... Not sure if I will. The P0342 and P0102 codes, at time of this post, won't move past "pending codes". Still randomly dies then catches itself.
Seams the OEM fuse box supply cable was 4ga. And OEM alternator has a 8 grafted on it.
Also seams the charm.li/Chevrolet/2009/Silverado 2500 4WD V8-6.6L DSL Turbo/ for free services manuals is down..
bought 10' of 2ga and 5' of 4ga cable and some 1/4", 5/16", 3/8" eyelets for both cables.
Remade the battery to fuse box cable along with alternator to battery cable. Haven't done the starter cable yet... Not sure if I will. The P0342 and P0102 codes, at time of this post, won't move past "pending codes". Still randomly dies then catches itself.
Seams the OEM fuse box supply cable was 4ga. And OEM alternator has a 8 grafted on it.
Also seams the charm.li/Chevrolet/2009/Silverado 2500 4WD V8-6.6L DSL Turbo/ for free services manuals is down..
FYI, The Alternator positive cable Is Fusible link wire.