My son has a 95 XJ that has been hard starting for quite awhile, and this evening just flat didn't want to. He thinks the problem is the fuel pump. Pardon me if this sounds a bit voodoo like, but a friend showed him a technique where you literally get someone to kick the gas tank and that somehow seems to stimulate starting. It seemed to work this evening.

Has anyone ever heard of this approach and perhaps has an idea as to what it is an indication of (i.e., the real problem). Seems like the old TV sets where you had to know just where to whack it to make the picture right (this shows my age).

Please excuse if this has been addressed before. I can't actually imagine that scenario, but it did start right up after minutes of trying once his friend kicked the tank. I am not kidding about this, but do feel quite stupid to even be describing it and asking the question.

 

I would check your connection at the fuel pump first(wiring). I had a Honda that I thought was the fuel pump. upon removing it i found a wire was loose in the connection.

 

welcome.

No starts are mostly related to either no/poor fuel delivery or no/weak spark. Key is to find out which you have.
What makes him suspect the fuel pump? Does it prime (listen to it in the back whining for 1-2 seconds) when the key is turned to 'on' (not run)?
the only thing I can think of that results from kicking the gastank (with the fuelpump assy attached to it) that a loose connection might be 'kicked'to connect. The 95 has the pump assy 'in front'and not on top, so should be easier to inspect/replace if that's what needs to be done, but thats for later.

 

Easiest way to check is to get a mechanical fuel guage and turn the key to run. The fuel psi for a 95 should be 31 psi I believe. A bad NSS can cause no start issues. Search for the NSS write up for removal and cleaning.

 

The mechanical gauge reading would only be meaning something, if you did that in a no start situation, since with a normal start it will likely be normal.
Fuel pressures for the pre-update are lower IIRC, more in the 35-39 PSI range.

NSS could indeed cause no start issues, but in that case it will not even crank. Not sure if the OP's no start issue is a crank-not start or no crank-no start.
If suspected, before actually R 'n R it, wiggling the shifter, or trying to start in neutral i.s.o. park might give a good clue...

 

My 95 Factory Service Menu says with engine at idle fuel pressure should be 31 psi. 39 psi with the fuel vacuum line disconnected.

 

So IRC...

 

It is a case of crank-not start, and I should have mentioned it is a manual. For quite a while, it has been in a state where he would crank it a long time and it would finally start, but this latest thing has him thinking it's the fuel pump. My personal thought is that it is probably something like a bad/loose connection if that kick really stimulates the start; I don't have that much familiarity with Jeep, but I do understand electrical connections and basic physics so a bad connection seems the more likely scenario, especially since it runs fine once it starts.

Thanks for all of the quick responses from folks so much smarter than I am about this vehicle.

 

That's telling you put a pump in it b4 you end up with a tow bill. Same principal as hitting starter with a hammer.

 

So that kinda rules out a bad NSS haha. I have no experience with manuals, but there is a think you could try to see if the fuel pump is subpar: the Poor Man's Prime.
Turn the key to the on (not RUN) position (fuel pump should be heard priming for 1-2 seconds), Turn key back to off and repeat this 3 x. Then try and start. If this significantly improves starting time, it could mean eitheer your pump is poor or a drain back valve is not holding the pressure in the fuel line.
It will not harm your engine in any way, and in fact I've been doing it for quite some time...don't feel like dropping the tank and replacing the fuel pump assembly just yet..