I have a 1988 Jeep Comanche Pick-Up truck with 210,000 miles. It has an inline 6 cyl 4.0L fuel injected engine. It runs like a champ except: lately it doesn?t want to start in the morning if the weather is cold. I live near the beach in California near San Luis Obispo. It doesn?t get too cold here but sometimes it gets in the mid to low 40?s at night. I have within the last month replaced: spark plugs, spark plug wires, distributor cap & rotor; oil, air & fuel filters and the gas cap. The battery is good with a full charge. When I try to start it first thing in the morning, the starter cranks just fine but the engine won?t kick over. If I leave it to set for awhile till the temperature warms up (near 65 or higher) it will start up just fine and runs great all day. I should also mention that I don?t have a garage to park in, I have to leave it parked outside all night. also about a couple of months ago i blew a radiator hose and sprayed coolant all over the engine. Sure hope you guys can help me figure this out.
Thank you for your advice,
I suspect that 1988 Jeep has a carburetor and the choke is not coming on. Find a shop with an older mechanic who knows what a carburetor is and you should be up and running quickly.
Note: it may be sticking and just need to be cleaned or there may be more to it. Good Luck
Maybe the temp sensor is going bad?
Hi Joe I think you missed it but its a FI vehicle stated in the OP.
You might have missed it Andrew, but he said it has a problem when the temps get down in the 40s but is fine once they get up to about 65. It can get chilly in Florida. Like it does when I go there.
I agree with starting at the choke, assuming that it’s carbed.
I’m not 100% sure, but I think all of the 4.0’s were fuel injected. At least I’ve never seen a carbed one, so combined with the fact that the OP claims it’s fuel injected, I’ll bet it’s fuel injected.
I’d second the CT sensor and also add that there may still be some air in the cooling system as a result of the radiator hose blowing, which could be making the CTS give weird values to the computer.
FI… as in Fuel Injected… not FL as in Florida.
The Jeep is fuel injected 
Whoops! Mea Culpa.
In that case I’ll go with the temp sensor.
My guess is a moisture related problem due to the cool tmps at night. Is there a garage you can park it in overnight and see if the problem persists?
Try this on the next cold morning: Turn ignition on (dash lights come on), but do not start the engine. Turn off after a few seconds, and leave off for a few seconds. Then try to start normally. If it fires up, you may have a weak fuel pump. Also, you may need to replace the coolant temp sensor (CTS) and the ambient air temp sensor.