2000 4Runner Won't Start but Cranks after Battery Replacement

[FD7683]

Hello, my old runner finally needed a new battery after 7 years of light use. I figured no biggie, i'll just replace with another 24F battery and move on - nope it is not firing up. It keeps cranking and cranking it will not fire up no matter what. I replaced the corroded terminals and still same problem. I know I popped a fuse somewhere but can't locate it. Connections all look good nothing seems out of the ordinary but the truck is 26 years old a broken wire could be a possibility. This is a first after 15 years of ownership.

Please help! I know its not either reaching spark, gas or no communicating to ECU. Thanks.

 

[olerunner]

You know you popped a fuse? How do you know? And if you know you have popped one, it is critical you find the fuze. This will tell you what component to track down. I assume youve checked both fuze boxes. Does your rig have aftermarket battery leads with an independant fuze in them?

"I know its not either reaching spark, gas or no communicating to ECU."

I'm not sure what you mean here. Have you eliminated these three as possibilities or are all three of those possible culprits in the issue?

 

[FD7683]

You know you popped a fuse? How do you know? And if you know you have popped one, it is critical you find the fuze. This will tell you what component to track down. I assume youve checked both fuze boxes. Does your rig have aftermarket battery leads with an independant fuze in them?

"I know its not either reaching spark, gas or no communicating to ECU."

I'm not sure what you mean here. Have you eliminated these three as possibilities or are all three of those possible culprits in the issue?

Its all pure guesses I don't really know whats going on. I checked the EFI fuse and its good. Only one I haven't checked is the main starter relay. The connections are OEM. Is there any other fuse I need to be on the lookout?

 

[Hungryhawk]

Can you hear the fuel pump with key on?
Old battery cables can corrode under the insulation. Very hard to troubleshoot unless cable terminal is suspect.

 

[phattyduck]

Can you hear the fuel pump with key on?

3rd gen 4Runner does not prime the fuel pump with key on. It only runs in the START position or the engine is actually running (ECU controlled).

Do things like the radio work? Any lights on the dash with key-on, engine-off?

-Charlie

 

[FD7683]

All the lights work and everything like it should. I was thinking the immobilizer was not reading the keys but it doesn’t make sense if both master keys were erased from the computer. I haven’t really had time to dig into it but tonight I will check the fuel pump operation and crank sensor. I may also buy a spark plug and check for spark to eliminate that but it’s very odd how it’s not firing up.

Also the battery terminals look good but not perfect I think I will replace the ground again later since the corrosion from the old battery was pretty bad. Will also check relay fuses again but with multimeter this time.

 

[olerunner]

Not any specific fuse no but there are many that can cause a no start. So unless youve confirmed all of them are goos to go I'd start there

 

[FD7683]

Update: The truck is bipolar, it started right up like nothing happened to it when I was beginning to diagnose. My theory is the spark plugs were soaked in gasoline and not creating a spark. Going back to when the new battery went in I reused the old trash terminals and broke the negative post clamp. Tried to start anyways and didn't want to. Kept cranking and cranking and nothing. Next day with new posts same thing but switched the EFI relay with another and still nothing. Today it fires up like nothing... Not sure if I should trust the runner.