To make a long story short, (or sorta long to ask one quick question)
My 1999 TJ 4.0 died on me in the woods the other day. Crank, but no start at times it sounded like it was about to try to.
At first I thought it was a water issue, but I couldn't get it dried out on the trail towed it out and trailered it home.
A few days later I winched it into the shop.
The more I thought about it the more it sounded like it was starving for fuel.
Checked for codes with a scan tool, no codes active or stored.
Plugs, wires cap and rotor were new about a thousand miles ago or less.
I put a fuel pressure gauge on the rail, key on and it came up to where it should. Cranked it over and the damn thing started.
I shut it off, and the fuel pressure dropped pretty quick. I isolated it to one or more injectors leaking.
I started it back up and ran it a little more, it was running a little rougher as it warmed up more.
I ordered new injectors. Even though I was skeptical that they would suddenly be so bad it would die and not start, they were still in need of replacement.
This morning I installed new injectors. Fuel pressure is now holding with engine off and running good in the shop.
I ran a few errands, about 10 miles of driving.
When I pulled in the yard, and it was idling every now and then I would hear a little lope or maybe a miss, intermittent and not severe.
Checked the plugs, all looked good, almost brand new looking yet.
I checked the signal voltage on the ignition pickup coil 5.153V, (Not cam sycro) I was expecting no more than 4.5V.
I back probed the connector and connected a scope, and consistently saw 5.153V on the signal.
I pulled out the FSM and the recommended check is crank it over until it's in a triggered position and it said you should have 5V....... 5V?
I didn't test the crank position sensor yet, because the 5V thing has me baffled.
Shouldn't that signal voltage be no more than 4.5V?
I was always under the assumption that any signal voltage under .5V or over 4.5V would generate an error code for a 5V referenced sensor.
Am I wrong?
My 1999 TJ 4.0 died on me in the woods the other day. Crank, but no start at times it sounded like it was about to try to.
At first I thought it was a water issue, but I couldn't get it dried out on the trail towed it out and trailered it home.
A few days later I winched it into the shop.
The more I thought about it the more it sounded like it was starving for fuel.
Checked for codes with a scan tool, no codes active or stored.
Plugs, wires cap and rotor were new about a thousand miles ago or less.
I put a fuel pressure gauge on the rail, key on and it came up to where it should. Cranked it over and the damn thing started.
I shut it off, and the fuel pressure dropped pretty quick. I isolated it to one or more injectors leaking.
I started it back up and ran it a little more, it was running a little rougher as it warmed up more.
I ordered new injectors. Even though I was skeptical that they would suddenly be so bad it would die and not start, they were still in need of replacement.
This morning I installed new injectors. Fuel pressure is now holding with engine off and running good in the shop.
I ran a few errands, about 10 miles of driving.
When I pulled in the yard, and it was idling every now and then I would hear a little lope or maybe a miss, intermittent and not severe.
Checked the plugs, all looked good, almost brand new looking yet.
I checked the signal voltage on the ignition pickup coil 5.153V, (Not cam sycro) I was expecting no more than 4.5V.
I back probed the connector and connected a scope, and consistently saw 5.153V on the signal.
I pulled out the FSM and the recommended check is crank it over until it's in a triggered position and it said you should have 5V....... 5V?
I didn't test the crank position sensor yet, because the 5V thing has me baffled.
Shouldn't that signal voltage be no more than 4.5V?
I was always under the assumption that any signal voltage under .5V or over 4.5V would generate an error code for a 5V referenced sensor.
Am I wrong?
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