My 2008 Grand Cherokee CRD is starting of have some issues starting in cold weather (< 30* F). When I turn the ignition the battery will continue to crank the engine but the engine doesn't seem to catch, every once in a while after letting it crank for a while it'll catch but it seems sporadic. In the past couple of months I've replaced the entire glowplug system (plugs, wires, & module) so I am sure that the glowplug system is in good working order. I've also replaced the air filter (thinking that there might be a clog but there wasn't).
The only other thing I can think to check is my battery, I've taken it to the local auto store to have them hook up to their testing machine but it showed the battery being in good condition. The guy that helped me out also said that I should test the charge when I get home and then after I let it sit for a while to see if it was losing charge (after sitting for ~12 hrs the Amperage had only dropped by .2). I'm not sure what the CCA's are on the stock CRD battery but does this sound like an issue of not having enough CCA's?
When I do have the ability to plug the block heater in it fires up every time on the first shot if that is helpful info.
i have a similar problem and i've made a post about it. if the engine is slow cranking, it could be your battery. either way it's pretty easy to check if your battery is ok or not wiith a volt meter. let the jeep sit for a few hours and it should measure 12.4-12.6 volts not running. i would bet it has something to do with your fuel system from the tank to cylinder (low pressure pump, fuel quantity control solenoid, high pressure pump, fuel pressure control solenoid or a leaky injector in that order). if my jeep sits for more than 4 hours it has a prolonged crank. i turn my key twice and wait for most of the dash lights to go out before starting and it usually starts with no problems. its a PITA but i'm learning to live with it or least try to forget about it.
i had the low pressure pump replaced under warranty and replaced the fuel pressure control solenoid myself and neither fixed the issue.
i'd recommend just waiting longer before you start, but if you decide to get it looked at i'd be really interested to hear what, if anything, was done to address the hard start.
2008 WK CRD Limited 4x4. Every available option package
I agree with jigadog, probably the battery.
For months I had the exactly same hard starting problem you described. Then about a month ago, in subzero weather it decided not to start at all.
My battery was toast, I noticed an immediate difference in how the entire jeep ran with a new battery.
If battery is over 5 years old replace it. Have you replaced your fuel filter? If so make sure you are not getting any air leaks into fuel system. I doubt this is your problem however as you state it starts right up if plugged in.
2007 WK CRD QDII, GDE HOT tune. 275/55/18'' on Sahara's, SRT8 suspension.
2000 Jetta TDI (hers)
2006 Liberty CRD (sold)
3 VW TDI's (sold)
Thanks everyone for the responses, I’ve gone back through the entire glowplug system and all of the wires are providing adequate amperage at ignition and all of the plugs are working as well. I have also replaced both the air and fuel filters (in the process of replacing the fuel filter I made sure to reconnect the glow plug ground). I have scanned the computer and it is not throwing any codes. The only thing I can think to check when I get home is the fuel lines to make sure that they are connected tight and not leaking (allowing air into the system). Other than that I think I’m going to bite the bullet and get the $220 battery. I’ll be headed up to the mountains this weekend so it’ll be a good time to test out the new battery, I’ll report back as to what I find.
Had the exact same issues after I had already replaced a few glow plugs and the control module. The new battery fixed it all, it wasn't dead and still works fine as I have it out in the garage. Something seems to happen to wk batteries as they age that the crd systems do not like. Can't really explain it, but this situation seems to be occurring more and more.
With a coupon code I think I paid around 140 for an agm battery from advance auto.
I also found in my CRD is that the positive lead off the battery was severely corroded so between that and the stock battery not being up to par, I had starting issues as well. New cable and battery took care of it. Check that since you have already checked and dealt with your glow plug system.
Originally Posted by samgm2
And yes, I am an exceptional scientist and engineer.