my bro in law first put post up about jeep not starting. heres the deal pulled in garage to fix top left over night came to get get next day wont start" it will start if you put heat to it and a shot of startin fluild "ive changed the coil and the crank pos. senor cap is knew along with plugs and button i pulled codes the old fashion way with the key getin code 13=map senor could that not let it start cold "Ill take all the help i can get"

thanks steve <img src="/forums/images/graemlins/scared.gif" alt="" /> <img src="/forums/images/graemlins/patriot.gif" alt="" />

Ok I'd try to sort out if it was the HEAT or the starter fluid that helped it to start. Prolly it was not both. So get it to not start again and then do just the starting fluid and then the heat after that to see..
Big Jim <img src="/forums/images/graemlins/pfft.gif" alt="" />

ok ill try that thanks for the help <img src="/forums/images/graemlins/frown.gif" alt="" /> <img src="/forums/images/graemlins/patriot.gif" alt="" />
thanks big jim

More diaganosis...

Noticed that when turning key just before starting (ACC ON) the normal dash lights, dont come on... No Check Engine Light. The Light will come on occasionally - very few if turning off and on. If C.E. light does come on it will start.

Could this be ignition switch / computer (ECU)??

Where would the ECU be on the 94 YJ (sorry posted as 95)

Thanks again

The ECU is on the firewall under the brake master cylinder.
Have you checked the vacuume lines going to the MAP sensor? They get old and crack. Where are you applying heat to?