Weird Starting Issue After Truck Sits More Than A Few Hours

[HACK BLOCK]

There's no rhyme nor reason to it. Cold motor is does it sometimes. Hot motor it does it sometimes. I'm trying to eliminate e85 coupled with low ambient temps as the cause. Still bringing my alcohol percentage down. Today it didn't want to fire first thing in the AM, but I didn't get temp checks on it then. Ran a few errands and every other start (after only sitting 20 minutes) would give me trouble. Ambient ranged from 50-75* today. Just now, after it sat for 3 hours it fired right up, so my temps aren't a good test. However, it did sit for a good while with key on RUN which may be what it needs. I've tried to "prime" the pump 2-3 times before each start attempt but that doesn't seem to do anything, either. I guess I'll try and get alky down to 10% and also slap my pressure gauge on and let it sit for a while and see what gives.

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Edit. Idle fuel trims were pretty much 0 on short term and stayed at -3% LT. O2's switching as expected. Spark from 17-21*.

sorry how do I get tech 2 on a computer? I think I'd rather this than my handheld especially if it doesn't reset when Turing on the engine

 

[mattbta]

sorry how do I get tech 2 on a computer? I think I'd rather this than my handheld especially if it doesn't reset when Turing on the engine

I bought a VCX NANO device and it came with a "modified" version of Tech2Win which is software for a PC. This device emulates Tech2, MDI, MDI2 and J2534 passthru and is USB.

 

[MassHoe04]

I believe the Tech2 can be hooked up to an older (Windows XP) computer to display and

sorry how do I get tech 2 on a computer? I think I'd rather this than my handheld especially if it doesn't reset when Turing on the engine

The GM TIS 2000 Tech2Win software is included with the Tech2 scan tool.
Was originally built for older (Windows XP) computers with RS 232 jack.

I think it will run on newer devices with USB port and the right connector.

I don't know if it is truly standalone or if the Tech2 head unit is still required to interface between the OBD2 port and the laptop.

I have not tried that out yet, so I can't tell you much more.