Jeep won't start the first several tries in mild to cold weather only

jeep
grand-cherokee

#1

I have a 2005 Jeep Grand Cherokee Laredo that won’t quite start as the temp outside begins to drop into the 70’s. It started doing this last winter and is happening again this fall. It sounds like it wants to start but just doesn’t get that final ummmmph to start. After several tries and several minutes it will start but how annoying is that! Again this doesn’t happen in warm weather only mild and colder. Any suggestions as to the cause of this problem and what to do about it? Thanks!


#2

Turn the key to the on position for a few seconds, then off and back on again for a few more seconds, then off again. Then start. See if that works. BTW, you are not stepping on the gas pedal before or while trying to start are you?


#3

Good idea to try above. Problems when the temp is colder than usual are probably either the battery isn’t supplying a enough juice, or there’s a problem in the cold-start enrichment. If you got a slow crank, ask your mechanic to measure the voltages at the starter motor during cranking. That would eliminate electrical/starter motor problems. To test if the mixture isn’t rich enough on cold start, your mechanic could spray some starter spray into the intake during cranking, see if that helps. If it solves the problem: the ECM is supposed to inject more gas the colder the coolant temp is. Either the ECM isn’t reading the coolant temp accurately, or for some reason it isn’t injecting more gas like it should even though it knows the coolant temp is low. The mechanics of how cold start enrichment is done varies car to car, so unless someone here has experience on this make/model/year, you’ll have to consult the manual to see how cold start enrichment works on your car, and go from there.