1997 JEEP TJ 4.0L won't start on first try

[rdeloach]

I've got a 97 wrangler w/ 112000 miles. Runs great, idles smooth.
The stupid thing will not start, even pumping the gas pedal.
However, if I stop and reverse the ignition and start cranking again, it fires right up. What is the deal? A local Chrysler mechanic said it could be several different things. Was wondering if anybody had this (or similar) problem and could point me in the right direction.
Money is tight and I don't wanna pay big bucks for diagnostics at the dealership. Would like to attempt the repair myself. Any ideas would be appreciated!

 

[xt master]

97 Should be fuel injected,dont pump the gas pedal.turn the key to the on position until you here the fuel pump stop running then turn the key to start it.

Has it had a tune up lately?
Check the fuel filter also.

 

[SteelHeadz]

I've got a 97 wrangler w/ 112000 miles. Runs great, idles smooth.
The stupid thing will not start, even pumping the gas pedal.
However, if I stop and reverse the ignition and start cranking again, it fires right up. What is the deal? A local Chrysler mechanic said it could be several different things. Was wondering if anybody had this (or similar) problem and could point me in the right direction.
Money is tight and I don't wanna pay big bucks for diagnostics at the dealership. Would like to attempt the repair myself. Any ideas would be appreciated!

If there's a possibility that you can borrow a fuel pressure tester, verify that your fuel pressure regulator is not leaking internally. if this issue occurs when the vehicle sits overnight or long periods of time , it's likely that your loosing prime at the fuel rail causing the long crank to start.

 

[DeadHammer]

I'm curious too, I have had the same issue with my 98 sport 4.0 from day one. I did checked the fuel system pressure and it was in spec checked all my electrical connectors for my under hood sensors, the fuel filter on my Wrangle is in the gas tank (part of the fuel pump / pressure regulator, as far as I know), it is a return less system. Some one once told me it could be a weak CPS sensor (crankshaft position sensor) but I don't have the right equipment or specs from the factory to check it so I always cycled the key twice.

 

[DeadHammer]

If there's a possibility that you can borrow a fuel pressure tester, verify that your fuel pressure regulator is not leaking internally. if this issue occurs when the vehicle sits overnight or long periods of time , it's likely that your loosing prime at the fuel rail causing the long crank to start.

When I checked mine it did seem to hold pressure for a long time at the injector rail, I left the gauge hooked up for about 30 mins.

 

[SteelHeadz]

When I checked mine it did seem to hold pressure for a long time at the injector rail, I left the gauge hooked up for about 30 mins.

If the Pressure drops 10 psi in 5 minutes, the fuel pressure regulator or the pump module itself could be at fault. What we've found was on some of the GC's the fuel rail pressure will drop 10 PSI within 2 minutes. the cause was 2 O-rings on the fuel pump within the module was leaking the fuel back into the tank instead of holding it on the lines and fuel rail. on some TJ's was the regulator itself. Some testing will direct you on which one is at fault.

 

[rdeloach]

OK gents, played around with it. If I cycle the key 3-4 times (not cranking) on & off, she fires up. Twice isn't enough, but 3 usually gets it. Not something I want to continue to do.Do we still think it's the losing prime at the rail? Is the pump built into the sending unit in the fuel tank? Can you purchse it seperate from the sending unit? Thanks again...

 

[SteelHeadz]

Yes, the regulator is part of the module. heres it's location.

 

[Crazy4diesels]

I wonder if the signal to turn on the fuel pump might not be getting through on the first try. The ECM is supposed to turn on a relay (located in the underhood electrical box) and the relay powers up the pump. If I recall, when you turn on the ignition the ECM runs the pump for a few seconds and then shuts it off until it sees the crank cycle. After cranking the ECM keeps the pump on as long as the engine is running. If you look closely at the relays in the electrical box you'll see that several are of the same part number. As a test you could try switching the fuel pump relay with some other one of the SAME part number. Then see if the problem is still there. While you have the relay out look at the male prongs and look into the female sockets - be sure there is no corrosion.

Some info on the pump module... The fuel pump is part of the module. You have a one piece pump, filter, regulator, sending unit device which comes pre-assembled as one convenient, expensive part. I think I've seen aftermarket filters out there but your filter probably won't clog for a long time (I think it's "self cleaning" - i.e. dirt falls off and settles in the tank). For the pump you might be able to find an aftermarket replacement which will require a little rework of the assembly to install - you might try NAPA for that. If your tank skid has been crushed upward the module may have been wrecked since there is almost no clearance between it and the bottom of the tank. Best of luck - John

 

[rdeloach]

Swapped fuel pump relay w/ horn relay. Didn't fix it. My problems are never that easy to solve. Gonna try and find a pump/unit thingamagig online. Drop the tank, pop the old one out, drop the new one in and plug up the wiring harness. That easy, wouldn't you think?

If it turns out to be bad o-rings, I can return the 300 dollar pump. I found several OEM replacements online.

 

[SteelHeadz]

And don't forget the Keg of beer.

 

[rdeloach]

And don't forget the Keg of beer.

The pump comes with the keg, doesn't it?

 

[SteelHeadz]

The pump comes with the keg, doesn't it?

Or is it the Keg that comes with the pump?

 

[black87yj]

when i bought my 98 tj it was the same , took it back to dealer who put a new fuel pump in ( free)and it worked just fine ever after !

 

[rdeloach]

Picked up a OEM pump on Ebay for $170. Plan on installing next weekend.
Wish me luck...

 

[riden dirty]

I'm having the same problem. Did the new pump do the job? Anyone recomend adding an exterior inline fuel filter to the system? If so,what are the specs or guidelines?

 

[Crazy4diesels]

I would not modify the fuel line for an external filter. These are "high pressure" pumps and a leak could spray gas all over the place. IMHO this is why there are so many car fires nowadays. A little leak, gas sprays all over the place and ignites - WHUMP the whole engine bay is in flames. The old cars which ran 2 to 4 PSI would only dribble gas out of a leak. The in tank filter should suffice for a long time (like over 100,000 miles). Best of luck - John

 

[bud21ko]

I bought a 2004 Jeep Wrangler. Here lately when I go to start it, the ignition will not turn over. I try it for about 10 sec, stop and try it again and it starts. Are you supposed to pump the gas pedal for 2004 model.

I've got a 97 wrangler w/ 112000 miles. Runs great, idles smooth.
The stupid thing will not start, even pumping the gas pedal.
However, if I stop and reverse the ignition and start cranking again, it fires right up. What is the deal? A local Chrysler mechanic said it could be several different things. Was wondering if anybody had this (or similar) problem and could point me in the right direction.
Money is tight and I don't wanna pay big bucks for diagnostics at the dealership. Would like to attempt the repair myself. Any ideas would be appreciated!

 

[superj]

no, you don;t pump any fuel injection systems.