Q: Cold Starting Problems

asked by on November 18, 2016

My 1998 chevy blazer will not start in cold weather at all it cranks forever till the battery does but will not actually start having a hard time finding root cause online some things have said ignition switch could be it or mass air flow sensor but would like some advice before going crazy on parts also had someone tell me possibly battery cables even though they look good any ideas??

My car has 210000 miles.
My car has an automatic transmission.

As a general rule, car engines do not like cold weather and do not do operate as well in cold weather. When you start your car in the morning and turn the key to on, the coolant temperature sensor immediately reads the temperature of the coolant and relays this to the computer indicating that the coolant is cold. The computer then knows at this point that it needs to enrich (add more fuel) the air/fuel mixture at startup due to the change in air density. When you start the car, you will notice that it idles high for a period of time until the engine warms up. This is the enrichment cold start process. In contrast, the old carburetor engines required you pressing the gas pedal before starting to set the choke position and give a squirt of fuel into the engine via the accelerator pump. This was necessary because the carburetor does not feed fuel as efficiently as a fuel injection system does at low (starting) RPM. A cold engine also needs a little extra fuel to compensate for questionable vaporization at low temperatures.

The fuel injection system does nothing until the engine is turning (starting or running), so pressing the pedal before you start will make no difference. The fuel injectors work at any RPM, so a choke is not necessary. The computer simply feeds a little extra gas through the fuel injectors to start the engine. Cold temperature fuel delivery is also managed by the computer which checks the mixture with oxygen sensors. With that said, you may have an issue with a faulty oxygen sensor which is what provides feedback to the engine after it starts as exhaust gases flow through the catalytic converter and past the oxygen sensors. I would recommend having an expert from YourMechanic come to your location to diagnose your oxygen sensors and cold start.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

What does this code mean P0420 ? 1997 Chevy Express 1500

Hello - the P0420 code means the catalytic converter has lost it's ability to burn residual fuel. This could be due to an engine condition that has clogged the catalyst, or a failing oxygen sensor that is not adequately monitoring...

How do I adjust the volume in the infotainment system?

Adjusting the volume in the infotainment system is very easy. Simply rotate the VOL knob until you reach your volume preference. The volume will increase when the knob is rotated clockwise, and decrease when the knob is rotated counterclockwise.

1998 chevy suburban 2500 4x4 7.4 / 4l80e limp mode?

If the check engine light did come on and the trans went into limp mode, often there will be a fault code stored to shed some light on the problem. The trans fluid level and condition can be checked and...

Related articles

2012 Chevrolet Cruze vs. 2012 Hyundai Elantra: Which One Should I Buy?
When you’re looking for a four-door sedan, you’re likely interested in a smaller family car that still offers decent styling and looks, great gas mileage, and a comfortable interior that will keep your family safe as you’re driving. While not...
How to Get Ice Off Your Windshield
Windshields need de-icying when ice accumulates in winter. Ice is removed by scraping with a credit card, spraying de-icer, or using warm water.
How Long Should It Take a Heater to Warm Up in Cold Weather
When When you turn on your car’s heater, it should start blowing warm air. If the engine is already at operating temperature, this should happen immediately. However, if your engine is cold, it will take longer and if the weather...