Strange starting issue...??

[BLHTAZ]

I know I have not been around in a while, and that's because I have no time for life outside of work & school right now, but the MJ is having an issue and I don't have time to spend searching for what it is.

 

When trying to start it, sometimes it starts with no problem, but others it acts like the battery is going dead, turning over very slow or just clicking. If we turn the key back off, then try again, it ususally fires right up. Last night I got in it and it turned very fast, then slowed way down, but I kept the key turned and it started to speed up again and started just fine. The first time it happened, I thought the battery was dead, but that is obviously not the case. I have only had time to check the connections at the battery so far--they are good, clean, and tight. The battery is about 18 months old and the cables are less than a year old, new from the dealer.

 

I may have an hour or two to work on it tomorrow (Sunday 9/6), so any input on specific things to look at would be greatly appreciated. :cheers:

[aemsee]

Hey Brent! Good to "see" ya :waving:

 

I would check ALL cennections for the strater, at the starter and the main ground from the block to the battery. A voltage drop test is the best method. Any chance it could be the starter itself? How old is it?

 

Something I have done in the past... If it is cranking slow, use a pair of jumper cables and run one from the positive post at the battery to the starter terminal. See if it cranks better, if not, then the positive connection is probably not the issue. Then do the same thing with it, but run it from the negative post to the housing of the starter, and try again.

 

If it doesn't turn better with either of the cables hooked up, just recheck the jumper clamps to make sure they are well connected, and if so, it usually points to the starter. Redneck diagnosis at its best!

 

I know you said you checked the cables at the battery, but did you pull them off and make sure you see shiny metal? I am amazed at how much resistance just a little patina of dull grey corrosion on a battery post has.

[dakal]

x2 :popcorn: x2

[Geonovast]

How's the main ground from the back of the block to the firewall? I've had loose grounds cause varying connection problems before.

[BLHTAZ]

Thanks guys. I'll let you know what I find when I have time to check it out.

 

I have a 12 slide powerpoint presentation on the digestive, pulmonary, and cardiac systems due tomorrow; then I have to pick my wife up at the airport coming back from Jamaica. I'll try to squeeze in a little time for the MJ somewhere... :dunno: ;)

 

OH...WAIT...Monday is Labor Day and I have the day off :clapping: . I'll work on it then :smart:

[BLHTAZ]

Thanks for all the tips guys; it turned out to be a bad battery. :cheers:

 

After going over all the suggestions here, removing, inspecting, and cleaning connections all over the place, I still had the same problem. I took the Yellow Top out of the YJ, put it in the MJ--problem gone. I load tested the battery from the MJ just to be sure, and sure enough, it was dropping to between 6-8 volts under load. The really strange part was, it would climb back up to 12.7 volts within about 10-15 seconds with the load on it.

 

Anyway, $98 later and problem solved.