1970 Chevrolet El Camino, 5.3L LS Engine, 4L60E Transmission
Device and software:
vxdiag vcx nano for gm bi-directional scanner and Tech2Win diagnostic software for LS engines and electronic transmissions
Why and where to get the vcx nano?
Need to solve a difficult intermittent spark plug misfire problem on the LS engine.
My cheap ELM327 and OBDLink MX devices would certainly indicate a general purpose GM P0300 DTC code for misfire but only rarely could I get them to show a P0308 code for cylinder 8 misfire. LS1Tech and Gearhead-EFI websites reviews encouraged me to get the vxdiag. The NANO that I purchased is specifically for GM vehicles and this particular model connects via a supplied USB cable on one end with the standard OBD2 data link connection on the other end.
The VCX NANO device was about a hundred bucks with free shipping.
NANO helped me solve the problem. Here is the working experience.
Once I got my NANO device up and running, it turns out that I had a bigger misfire problem than I thought across every cylinder but cylinder 2. With this many misfire problems in an LS engine, we are told to start looking for bad or missing engine grounds and this makes perfectly logical sense.
So I did that with three copper lug soldered half inch braided wire ground cables from the M10 x 1.5 bolt holes in the ends of each cylinder head directly to the negative battery post. I also checked the existing wire harness to the PCM bundle of ground wires at the back of the driver’s side head. No change – I still had seven cylinders worth of random misfires confirmed with an old school engine timing light – not any false misfire. Yet, the spark plugs looked good and I tried swapping coil packs and plug wires without any success. And the engine actually ran surprisingly well without shudder during the periods of misfiring.
What’s left to fix on an LS engine with a whole lotta’ random misfires? The powertrain control module (PCM)!! Fortunately for my LS engine, they are cheap in the junk yards at $32 around here and big-time dirt cheap on Half Price Sale Days. And I have four of these 512k byte “P01” PCM devices and two of the 1 megabyte “P59” PCM devices for lab rat experimentation. I can also flash the operating system for free in these using Tuner Pro RT (for editing) and LS Droid / PCM Hammer – no money spent on HP Tuners credits or EFI Live fees. I popped in a 512k byte PCM and BOOM, problem solved, no more misfires. The misfire graphic on my NANO Tech2 computer screen was clean and clear. I have no idea what caused my misfiring PCM to fail and it is quite uncommon for these to fail but sure enough, it did. I will soon make a trip to the junk yard to replace the misfiring PCM hardware that is now resting in the trash can.
Another aspect recommending the VXDIAG VCX NANO is that control of operating system activity inside the PCM while my LS engine is actually running was not possible prior to buying the NANO. What I lacked was the ability to perform a “Crankshaft Position Re-Learn” that the NANO can easily perform. I needed to try this Re-Learn to see if it would solve my misfire problem mentioned above – no help here.
The NANO comes with support for “TIS2000”, an early LS engine diagnostic tool from GM that works from the 1999 vehicles up through and including model year 2007 – either the 512k byte “P01” or the 1 megabyte “P59” PCM devices – the only two types that GM offered on any vehicle during that span of years. After 2007, the also included “Global Diagnostic System 2” tool is used for 2008 and later vehicles up to maybe 2014. Everything I was looking at on the inexpensive OBD2 tool programs is contained within the TECH2WIN program that you get with the NANO and so much more.
There is also a “VX Manager” program that supports all of this and all three must be installed in a certain order for the licensing to properly activate. And don’t be surprised if the firmware on your NANO device needs to be updated – mine did. The You Tube videos are very good at explaining all of this. VX Manager also must be running prior to launching the “Tech2WIN” program, the main diagnostic tool.
WARNING: One of the You Tube videos mentions that his antivirus software detected that one of these programs contained a virus. With the installation on my computer, “Windows Defender” promptly detected the malware and quarantined it. I also run “PC Matic” and it detected nothing about a virus or malware. Even with its anti-virus definitions updated, PC Matic was allowed to scan my computer overnight after this installation and detected nothing. And Windows Defender for WIN 10 has not detected any problems since that first day.
The screen fonts on the TECH2WIN screen are also somewhat outdated from the mid-90’s but still quite usable and functional. The TECH2WIN software also works best with its own on-screen keypad rather than the laptop keyboard that we will normally be familiar with.
For what I’ve gotten for my hundred bucks, I’m happy.