- Thread starter
- #41
Yep, I figured as much.
I was playing with it to manually release pressure from the fuel system, then starting it up again. Started up just fine and right back to a normal pressure.
Crank no start - Not Immobilizer - Fuse Box (1 Viewer)
- Thread starter drjman
- Start date
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I was playing with it to manually release pressure from the fuel system, then starting it up again. Started up just fine and right back to a normal pressure.
YardPig
SILVER Star
Leave the gauge connected until it does the no start. Don't relieve pressure, it will slowly leak down over night as the check valve bleeds pressure. This is normal.
You can drive with the gauge attached. I always recommend carrying a fire extinguisher when your dealing with opening the fuel system.
You can drive with the gauge attached. I always recommend carrying a fire extinguisher when your dealing with opening the fuel system.
- Thread starter
- #43
Finally received my new VCI cable and got techstream again. The only codes I had stored was for the steering wheel telescopic motor (disconnected and not working).
I cleared those to start fresh and now i have the P1600 code again. I've had this off and on over the year since I put in the immobilizer fix with the EFI relay. I'm wondering if my fuse box is just getting worse and might be the culprit of the crank/no starts.
My rig has been starting up with no issues since I've had the fuel pressure gauge on. All the numbers on techstream looked good and the health check came back fine.
I really don't want to drop $600 on a new fuse box. ugh.
I cleared those to start fresh and now i have the P1600 code again. I've had this off and on over the year since I put in the immobilizer fix with the EFI relay. I'm wondering if my fuse box is just getting worse and might be the culprit of the crank/no starts.
My rig has been starting up with no issues since I've had the fuel pressure gauge on. All the numbers on techstream looked good and the health check came back fine.
I really don't want to drop $600 on a new fuse box. ugh.
YardPig
SILVER Star
Bypass - EFI Relay Bypass Kit (Immobilizer Fix) for UZJ100/LX470
There are other threads on Mud with a search dealing with the fusebox and bypassing it.
There are other threads on Mud with a search dealing with the fusebox and bypassing it.
- Thread starter
- #45
Maybe I wasn't clear, but that's exactly what I did about a year ago. It's been working great. I have my fuse line coming directly from the battery. My old 20A fuse slot was too far gone unfortunately.
Based on the FSM, it appears the EFI relay is linked to the fuel pump as well. On the new 100's, there's a separate fuel pump relay. I'm wondering if this is the next step in a deteriorating fuse box?
The crank no start feels the same as the immobilizer, but never a flashing red light. I did have a no start with a red light last week and an adjustment of my EFI bypass fixed it up quick. At least I know my red light is working!
YardPig
SILVER Star
Have you confirmed the fuel pump is getting constant voltage? There is a possibility of the fuel pump control module going south intermittently. Wire to the fuel pump direct with a test light in line...
100 Series Fuel pump relay location
100 Series Fuel pump relay location
- Thread starter
- #47
Should there be voltage even when not cranking over?
YardPig
SILVER Star
The relay/ecm will cycle the fuel pump for approx. 3 seconds to build fuel pressure when you turn the key to on. The relay will then become deenergized until such time as the ECM sees crank signal, then the pump will turn on constantly.
YardPig
SILVER Star
You could build a simple test light with a 12v automotive bulb, run two wires from driver to under the seat inspection panel. Could even run one 12v hot wire if you want to ground either end at point of termination. Can get a cheap universal taillight socket from the parts store or just use a test light with alligator clips.
Be nice to know for sure if it's fuel related and if something is interrupting the fuel pump voltage supply.
Be nice to know for sure if it's fuel related and if something is interrupting the fuel pump voltage supply.
- Thread starter
- #50
I'll get the panel in the rear torn out for access the next time the issue comes up. It's been running fine since Monday morning....I can't fix what is not broken!
YardPig
SILVER Star
So this issue actually has nothing to do with the level of fuel in the tank....or...?
I'd just tap into the fuel pump plug under the seat and confirm voltage when the truck dies or doesn't start. I guess in reality if you leave the fuel pressure gauge attached it will tell you the same thing.
I'd just tap into the fuel pump plug under the seat and confirm voltage when the truck dies or doesn't start. I guess in reality if you leave the fuel pressure gauge attached it will tell you the same thing.
- Thread starter
- #52
In the beginning, maybe 4-5 months ago, I noticed it only happened when there was a 1/4 tank or below of fuel. Recently, in the last month now, it has cranked and no start regardless of how much fuel is in it.
I'm currently below half and i'm running it down to see if that will trigger it.
YardPig
SILVER Star
I want to see this issue solved and a solution posted. Keep on it! Thanks.
- Thread starter
- #54
I appreciate the help! I'm thinking about changing the thread title to help with others searching with a related issues.
I'm thinking "Crank No Start Not Immobilizer"
I could not get fuel pump to run whatsoever by just turning IG to ON, without engine cranking.
Draining Fuel from gas tank?
Draining Fuel from gas tank?
I could not get fuel pump to run whatsoever by just turning IG to ON, without engine cranking.
Draining Fuel from gas tank?
Draining Fuel from gas tank?
- Thread starter
- #57
It FINALLY didn't start this morning. I've had the pressure gauge on since last Monday.
When I turned it over it cranked and didn't start and there was no fuel pressure. When it finally started, the pressure gauge went to where it needed, but it died immediately. Took another few cranks (3 I think) and it started up. This time I kept the rpms up for a bit to help out. It ran fine after that.
It was around 50 degrees this morning and dry out. I drove it all over yesterday with no issues.
When I turned it over it cranked and didn't start and there was no fuel pressure. When it finally started, the pressure gauge went to where it needed, but it died immediately. Took another few cranks (3 I think) and it started up. This time I kept the rpms up for a bit to help out. It ran fine after that.
It was around 50 degrees this morning and dry out. I drove it all over yesterday with no issues.
I've be waiting on @YardPig to comment, as was his idea to attach fuel PSI gauge. I've never done this test, but let me throw a few thoughts out here:
You may not have cranked long enough to build pressure. How long did you crank without starting?
Have you notice on the times it does start first try. Did pressure build on gauge before it actually started.
Not having meter on wiring at pump, we don't know if current was present at time of long crank no start. So: You may have a defective new pump. But you may have a short, so that power was not getting to pump.
You may not have cranked long enough to build pressure. How long did you crank without starting?
Have you notice on the times it does start first try. Did pressure build on gauge before it actually started.
Not having meter on wiring at pump, we don't know if current was present at time of long crank no start. So: You may have a defective new pump. But you may have a short, so that power was not getting to pump.
