Hard starting

I have a 1990 xj 99,XXX miles. I have done a ton of preventative maintenance. But one thing I can't do is fix the hard starting. It has always started i just have to turn it over for 10-15 seconds and pump the gas. Is it my timing? It has new plugs cap wires etc. Let me know if anyone else has experienced this and what they did to fix it. I know I could let it keep happening but I like everything to work great on the jeep.

Thanks in advance

I have the same ploblem I have a 92 with 4.0 .was told the CPS had it checked was ok then the cam sencer thats ok too. last thing I was told is fuel pump or presser regulator.havent checked them yet.Have went thru every thing I can think of. Seems a lot of the 4.0 have this ploblem.

It's probaby the check valve in the fuel pump that's gone bad. Try holding the key to on for a few seconds to prime the fuel pump before cranking the engine.

the check valve would that also be the cause of me having to give it gas when starting it?

You shouldn't have to give it gas. Try cycling the fuel pump a couple of times with the key and see if that helps. You can put in an inline check valve, I got four of them for OMC outboards for $10.
Remember that a Renix will crank a few revs. before it starts anyway.

Checked mine it seem the check valve is bad .Dont want to replace the fuel pump right now have seen some where you can install a in check valve dose any one know where the best place to get one .Check Oreillys they told me there is no such thing as an inline valve .any help? even when I do install a new pump fig a check valve would help anyway.

PM with name & addy...give me a couple of days to find out where I put them, I moved a few months ago and not quite sure where in the mess of equip. and parts they are, but I do know we have some .
I'll send you one.

Dizzymac how would I check my check valve?

How I knew was that my '90 (Renix) was taking longer than it should to start. Renix will take a few cranks before it receives the signal to start. Mine was taking about 10 secs b-4 it would start after sitting a while
If it had been running and I shut it off it would start right back up. Let it sit for a couple of hours and it was back to long crank times b-4 starting.
I would turn the key to on a few times to cycle the fuel pump and it would start normal ( the few cranks and then it would start.)
I installed an inline check valve (didn't feel like puling the pump) and it worked out real well.
There is a BMW check valve that you can buy if you can find one. I got ones for an OMC outboard motor, got 4 of them for $10 delivered from [email protected] they worked for me, look on eBay, I think thats where I found them

Found one today...I'll ship as soon as the PO is open.
I couldn't find one of the ones I had all made up, You'll have to take it with you to a hardware store and get a fitting that threads in to it and has a hose connection on the other end, think I paid around $1.50 for one,
The XJ uses two diff. size hoses from the tank to filter and filter to the fuel line. If I remember this goes to the 3/8" line.
You should notice some diff in it starting, I did.
Merry Christmas.