richmond910

Hey 88
it does have a valve on the fuel pump, it is new

94Crawler

Sorry for wasting your time on that one.....Atleast we can rule out vacuum lock.

ET JEEP

I believe the key to the problem is checking your fuel pressure. You, apparently, are losing fuel pressure overnight. This why you can start after 4-5 tries. You are building pressure during the start attempts. There should be a check valve in the system to hold pressure. It should be in the fuel pump. Look for a place where you may disconnect a fuel line. Then blow pressure into the tank. It should not flow. If it does flow into the tank the check valve is not holding. At the same spot you can tie in a test fuel pressure gauge and to see what the pressure is doing. Set a pressure reading then check it the next day.

richmond910

Hey ET
I just went yesterday and got a injector pressure testing kit, It did shoe that i'm loosing pressure back throught the line towards the tank. but the pump is new and the check valve is on the pump. I will try the blow back you sugested, I guess my old pump was going bad and the new one can be as bad itself. also there are no breaks in the line from the fuel rail all the way to the pump.

thanks

94Crawler

This was the case with my Grand. I ended up pulling a second OEM ZJ pump and it worked great! There's alot of junk in the fuel pump market.

gmv93

do we have immobilizer on US manufactured grands? on euro models immobilizer problems may cause similar effects with fuel pressure.

Mattnkc74

They didnt start that til 98 and even then it was optional on wranglers,cherokees and grands. The have the grey plastic head key.

richmond910

It does, its on the fuel pump, I think I have a bad check valve thats on the new fuel pump so Im taking if off again and return it, this time I'm bitting the bullet and buying one from the dealer, it cost 2X's of the auto zone but if it works it will be worth it. Let keep our fingers crossed.

thanks
Mike

richmond910

OK here we go, A new OEM fuel pump with new check valve, it did not work. I still have to turn the key on and off 4 to 5 times even if i do it fast it will start. this is driving me crazy. The cheap fuel injector test kit I got from Harbor Freight was peace of crap so now I guess I'm back to the injectors leaking down........

ET JEEP

Bummer. Did you ever do the test back to the pump? That was an important test. I still think it is fuel pressure. You will have to pressure test again. Set a pressure and check it the next day, see what you get.

richmond910

ET
I did do the test and it showd it was leaking bac to the tank, so I put in an new OEM $300.00 ouch! (I'm not working) and it did not fix it. the testing kit I used was from Harbor Freight it turned out to be junk. I cant afford a good one so I'm back to the injectors I guess, but now I cant afford to buy any of them now......
thanks

ET JEEP

Go to AutoZone and see if they will rent a fuel pressure test kit. You put it on a credit card and get a refund when you return the kit. Check to see if they have one. You need to test that fuel system to see if it still leaks and where. If no AutoZone try some of the other auto parts houses and see if they rent.

Sorry to hear you had to spend that cash. I know how it is.

OnAll4s

STOP... its not a fuel check valve. Chances of it being bad in 3 straight pump is way too great. (Btw dont ever buy fuel products from advance auto and such. Its all crap.

Im gonna bet that once you do get it started, the exhaust reaks of gas and it runs rough for a minute???

If so its a leaking injector. I know you said you checked one side and let it sit for an hour or so? But remember gas evaporates quicker than most liquids. This would be the best time to hit a junkyard or ebay and pick up the 703 injectors. Just put them on my 4.0 and in the first tank I saw a 2.4 Mpg increase, better response, and smooth idle. Plus it cost me about $60 all together. Now I dont have to crank it but once. Try the cheapest stuff first and even the most idiotic things. A lot of our trial and errors will show us overlooking the most basic and simple things.