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long starts and missfires


NAXJA Forum User
South Dakota
I have a 98 xj sport 4.0 and when i start it it takes about 5-6 seconds of cranking or I have to crank adn stop and crank again to start. After it is started it will missfire for about 10 seconds. Anybody have any idea whats wrong?
i would check your fuel pump, or fuel filter.... most likely the filter since its an electrical pump ( i believe it is electrical, could be wrong though) if it is a mechanical pump then it would be a better option.

replace the filter since its alot easier.... then check the pump if theres no improvement
did you replace the filter and clean the pickup screen when you replaced the pump? if so then replace the quick fitting insert (not sure of the proper name) for the return tube from the rail. It may be letting the rail go dry when the car sits for a while. Also, if you just turn it off for a couple seconds does it start back up ok?
Then it might be also one of the sensors or fuel filter. Also, there ise in tank fuel pickup line. Does the problem remain if you have a full tank? Also there may be a vacuum leak.

Just some ideas..
Is there more than one fitting, besides the one I had to dissconect to get the fuel tank out?

And if that is not the problem what sensors could it be or what vaccum lines would be leaking?

Thanks for all the help!