No gas getting to engine

[workingclass78]

Finally, Pics of my YJ

I just replaced the Crank sensor and there was no difference - still dead.

BUT - GET A LOAD OF THIS.

i POURED A LITTLE GAS IN MY CARB AND TURNED THE KEY AND IT STARTED FOR THE FIRST TIME IN WEEKS (FOR JUST A SECOND)

I HAVE REPLACED THE FUEL PUMP ALREADY

WHAT GIVES?

 

[XJNick]

Do you hear the fuel pump running? If so I'd check the filter and pressure regulator.

If it doesn't run, check the fuel pump relay. Place a voltmeter between the output of the relay. If the relay is outputing power check the wiring and/or fuel pump. If the relay is Not putting out power, check for power input to the relay and for signal input from the ignition switch.

-Nick

 

[workingclass78]

Hey Nick -

No I did'nt hear anything form the New fuel pump or the old Fuel pump.

I'll check the relay, I always had a feeling that something electrical was playing a role, maybe it is a damaged wire. I'll pick up a test light this evening. That will work to check for power right?

Worth mention, when this all began I had found out an old kill switch from the previous owner, it was acting out, every now and then. So I took it out. In your opinion are kill switches ever linked to the fuel system? I'm pretty sure that I removed it correctly, though me screwing it up is not beyond the realm of possibility. Funny now that I think back the day it died the old alarm from the previous owner that never made a peep was causing my lights to flash, including the red alarm light on the dash that had always been off. With the problem of the engine shutting down at random, could it somehow be tied to the kill switch?

Thanks Nick. I look forward to your reply.
I am thinking that I may have to compromise my pride and send it to the dealership, which I cannot afford at the moment, but will have too.

Matt

 

[Snitty]

do you have pressure at the fuel rail? push in on the shader valve and see if the fuel pump is doing its job

 

[XJNick]

Hi,

Ok it definately sounds electrical at this point. A test light will do, but a multimeter is much more effective in helping to find problems.

As far as the alarm system goes, it's really hard to say. All systems are different. Most of the time, however, (on aftermarket alarms) the alarm system will cut off a circuit coming out of the ignition switch, thus cutting power to the fuel pump relay and the fuel pump itself.

When I bought my 1997 TJ recently, I had the same situation as you... the previous owner had some crappy alarm system only partially hooked up. The absolute best thing to do is to completely remove everything that relates to the alarm system. What you'll need to do is reconnect any circuits that were switched through the system (as I said most likely the ignition circuits).

Once you have removed EVERYTHING that relates to that alarm system, you'll go back in there and hook things back up the way they should be (Note that a subscription to AllData will be extremely helpful). Of course I'll help as much as I can but nothing is better than lots of factory wiring diagrams :wink:

Also, I believe Car alams are completely worthless pieces of technology. However, A good Immobilizer system is very very useful, and can easily be made and installed by you on the Jeep to keep it safe (I installed a home-made immobilizer on my TJ and it works great).

Hope that helps :mrgreen:
-Nick :!:

 

[workingclass78]

I am headed out to look into the wires right now. In regard to the fuel rail, nothing is coming out. If I pour a drop of gas in the Carb. it runs for a few seconds.

Nick thanks again, I am going to investigate the wire hook ups from the alarm under the dash and I keep you posted.

 

[workingclass78]

anybody have a good 2.5 head to sell

Nick -

I got gas coming up to the fuel bar - HOW IT HAPPENED ALL OF A SUDDEN i HAVE NO IDEA.
I push the nipple thing in and gas comes out for the first time in months -

But when I turn the key it "sort of runs" for a tenth of a second and stalls -

NOTE - When I pour a little gas into the Carb she runs fine until that gas runs out.
I have been pressing the gas pedal and there is no sign of it flooding -

This is all post playing with wires. Is there a part or component responsible for getting gas beyond the bar and into the engine, because I know for sure that if gas got into the engine my Jeep would be running.

This is friggen nuts.

again thanks for your help

Matt

 

[XJNick]

Yes, the fuel pressure regulator, which should be on the fuel rail. It is a little cylinder with the incoming fuel line and rail attached to it, plus a vacuum hose on the back side. It is possible that it could get stuck closed.

So you solved the electrical problem? If the power to the fuel pump is still intermitten, I'd still bet on a bad relay (either the fuel pump or alarm system cut-out relay), or the ignition switch isn't making good contact.

-Nick :!:

 

[workingclass78]

I think I removed the alarm cut out relay, in fact I have it on the kitchen counter with me now. I'd like to say I solved the eletrical problem, but it kinda happened on its own spontainously.

I'll check fuel pressure reg. and the vacuum hose - in regard to the intermitent power to the fuel pump, if I get it to the point of running I'll just drive it to the shop, when the $$$ allows.

Nick you da man!

Awesome advice, I'll keep you posted.

Matt`

 

[workingclass78]

por 15

On the fuel bar - there are 6 wires/plugs and that is the extent of objects connected to the fuel rail. Other than a gas line - Are these plugs responsible for letting gas into the engine?

The only vacuum objects in the vincinity are a coffee can size canister, a smaller round cylinder shaped object about 4 inchs long next to it and other random vacuum lines entering the engine.

Now if there is gas in the fuel bar and the Jeep run when gas is manualy poured into the engine thru the carb, why cant the gas get from the bar to the engine. I am at a total loss.

I am just sitting in the yard staring at the engine and racking my brain for an answer.

Any ideas?

thanks

Matt

 

[workingclass78]

Now at the point where I turn the key and it starts for like 3 to 5 seconds and as soon as I hit the gas pedal, bang it dies. I can hear the intake when I hit the pedal it sounds like it is suffocating - Carb is burping etc.

 

[Snitty]

those wires/plugs are your fuel injectors.... they are the electronic valves that open and close intermittently to spray fuel from your rail into intake

there may be a relay or a fuse that controls these.... or... you may just have bad injectors... but these are all controlled by the computer, which tells them when to open, how far to open, and how long to stay open... if you are getting a bad signal from a sensor somewhere, it will not give those the right information.... the crank sensor and throttle position sensor will adjust the timing of them...the O2 sensor will adjust the quantity of flow

 

[XJNick]

Yeah, i just noticed that my 1997 TJ doesn't have that pressure regulator either :? I guess I was thinking of my Cherokee's I6 engine

.

I'm running out of ideas too. You've got spark and gas, but maybe not at the right timing? Maybe there is another sensor or wire harness with a loose connection? Have you verified that the ignition switch isn't corroded internally and cutting off power? The injectors are controlled straight from the ECU (computer), so I'd lean towards bad sensor, possibly that Throttle Position sensor.

FYI, your Jeep doesn't have a carburator (I think you've been referring to the Throttle Body?) :mrgreen:

-Nick :!: