1988 Comanche hard to start in the Cold

[SGT]

I’m having problems starting my 1988 Jeep Comanche when it’s very cold. I have changed the ignition completely and the Gas Filter. It starts perfectly when it’s in the 40s outside. Any ideas.

[87MJTIM]

We need more info: engine - 4 or 6 cyl, transmission, etc.  Complete your profile.  (Also, your location: City, State/Province)

 

What, if anything, have you tried?

[Billabob]

Mine is similar in the cold and I’ve found it best to make your way back from the battery. Check your battery voltage when you shut the car off and compare it to what it settles at by the morning. An old battery or one thats been discharged too many times will struggle to turn over even when everything else is perfect, the problem gets worse when it gets cold. Make sure your battery terminals are free of corrosion, a light sanding is an easy improvement. I cleaned mine and reinstalled with Oxgard which solved all of my hard starting issues. Check the voltages at your ignition relay behind the battery to further narrow down any wiring issues. The ignition slider on the steering column is another part that can cause starting issues and one that can easily be diagnosed in seconds with a multimeter. It is quite easy to jump your starter through the relay as well if you’re in a pinch

[neohic]

Moving this to Tech for more members to see it. 

[gogmorgo]

Are we talking slow/no crank, or just not firing? Also, what constitutes “very cold”?

 

One of mine likes to have the throttle opened a little or it won’t always start from cold once it’s down towards or below -20°F. It cranks over alright, coughs a little, but won’t catch and go without. My assumption is one of the 30-year-old temp sensors is reading a bit off so it’s trying to run way rich, and cracking the throttle leans it out enough to run, but it always starts so I’ve never really looked into it. Once it’s started and warming up it runs just fine, and it starts just fine with the block heater plugged in.

 

If you’re running 15w40 in your engine it’s not going to spin over nicely past 0°F. Might be enough to slow it down too much to start if your cranking system is getting weak.

[SGT]

2.5L

 

The engine turns over but takes up to 4 times before ignition. I replaced all the ignition. The Battery is New. In above freezing it starts immediately.

[cruiser54]

Remove the firewall ground. scrape to bare metal. Clean the connector and reinstall. 

should do the same on the block side. 

 

Or, add a cable from the firewall to intake manifold. 

[SGT]

The thing is if it’s above zero, it starts on the first try. The ground problem has been upgraded.

[cruiser54]

Test the IAT and CTS then.

 

 

[gogmorgo]

Have you run some gas-line antifreeze through it? It would surprise me if a little water freezing in the fuel system would cause it to start hard but still run fine, but if the difference is above/below freezing, that might be a strong clue.

[Eagle]

What do you mean by "I replaced all the ignition"? And how long does it take to start?

 

Have you driven THIS vehicle through other winters? If so, is it significantly worse than it was last year or the year before? Gasoline is less volatile when it's cold, so it's normal for starting to take a bit more effort when it gets down toward (or below) freezing.

[SGT]

Found the Problem. I had a kill switch installed and cut the battery off. This caused the Microprocessor to Reset. Kept it plugged in and it starts on the first Turn. 

[cruiser54]

Yep. Had no memory of the last setting of the IAC.