C5 Wont Crank/start in Cold weather , but warm weather in the day cranks perfect..

[ken2028]

Good Morning,

I have an on going problem with an Automatic C5 2000 Corvette. Every Cold morning around 45-50 degrees . I am having problems trying to
start this car. There is No sound, No crank. No security light Alert on. all dash lights working and visible when turning on. Dead Silence no crank.

During the afternoon when I get back from work, its warmer weather and the corvette starts up with no problem never failing. Since the car was recently purchased and by the looks of it was not properly maintained correctly.

I will list what I have done to rectify the multiple failures and problems, replaced parts.

- All new Rotors (Willwood slotted)
- All new brakes , included bad installed emergency brakes
- Oil Change Royal Purple.. flushed with 3 quarts synthetic oil after old , then added new oil Royal
- Bleed the Dark bad Brake fluids , Cleaned all the lines
- All 2 Serpentines replaced
- AC Pulley Tensioner replaced
- Upper Tensioner Replaced
- Repaired the Notorious ABS module Failure. Traction control Repaired!
- Replaced all Coolant lines except the lower one
- Replaced the Coolant Thermostat and housing
- Replaced the complete coolant reservoir , old leaking..
- Flushed complete old coolant with lots distilled water
- Removed the VATS from the Ignition that was intermittent faulty
Direct connection made with proper resistance on BMC for VATS, No Security problem
- Installed the LMC5 perfectly, I have done many
- Replaced the MAF sensor, Original was extremely nasty, could not clean it enough with MAF cleaner
- Replaced the intake Temperature sensor
- Replaced the broken outside front Ambient Sensor
- Repaired the front Speed sensor left side
- New 800 CCA Battery


Work in progress To be done
:: Both Valve covers replacements.. Leaking oil on the headers ( Oil Smell Burning) Annoying
:: Both front bearings replacement, both side are ticking rough, not so good
:: Rack pinion replacement
:: Replace the ignition Module.. It's old might as well..

I did not disable in the PCM the VATS. I know it notoriously plagued with problems.
VIN was verified in PCM that matches with car using PCHAMMER.

I know , If the Battery is low it wont allow you run the car, shuts off. Bad battery symptom
I cleared all the errors in the ODB, The only one that comes back is the MAF P0102. MAF has been replaced, installed correctly and error still shows after a while running.
P0102- MASS AIR FLOW (MAF) SENSOR Circuit Low Frequency

Possible ground problem??

I owned six C5 corvettes never had so many problems in one car.

Is the VATS in the PCM Disabling the START relays having some type of phantom issue when its COLD outside?

IS it the MAF Malfunction, and the VATS disabling the starter?

Reminder only happens when its cold

It's very difficult locating problem, Any experienced Help would be greatly appreciated.

[roadpilot]

I would have the battery checked out. A cell starting to fail
is my guess. I have had a similar problem Engine would start
but it sounded like it was turning a little slower. Bad battery.

[Y2Kvert4me]

I would suspect the starter motor.

If you're good with electrical stuff, I posted a lot of detailed info and troubleshooting steps in post 5 of this thread regarding intermittent no-crank issues. If you think it could be VATS related, then read that entire thread.

[Vette40th]

Battery or battery ground. Check voltage.. Let us know. 12.7 is great, 12.4 is when it is starting to show its age or deterioration.