2000 Tacoma 2.7L Cranks and Dies: Please Help

Glamisman, the FSM troubleshooting for all of these symptoms starts at fuel pump control circuit. The first step in that troubleshooting is to jump the FC pin of the ECM to ground, this causes the fuel pump to operate. The next step (in the manual) is to squeeze the fuel return line at the fuel rail and observe if there is fuel present and flowing (There is). As far as how much, or rate I don’t know because the troubleshooting does not call for using a pressure gauge or collecting and measuring a quantity. I can and will certainly do these things next to see if it’s a fuel pressure issue. One of the first things I did for the crank immediate stall was to replace the fuel pump with an OEM Denso pump and the fuel filter. Recently I replaced the fuel pressure regulator with OEM Denso. Yes one of those parts could be faulty but I doubt it, you can audibly hear the new pump running, there could possibly be some sort of blockage downstream though for sure.

Slater, I am not driving the truck. It has been sitting/being worked on since late November 24. The misfire happened and CEL popped last summer before any of the upgrades or parts installs. I then swapped everything I could think of to remedy that, plugs, wires, coils, injectors l, cleaned MAF etc. the misfire wasn’t persistent. It happened a couple times as previous mentioned. Then other symptoms would appear such as stall after 30+ minutes of driving (truck was running and idling fine and it would randomly run rough and stall). Every time an issue would appear, l would troubleshoot and attempt to fix it, not just wantonly drive with disregard of the issue.

Also, the truck has a single exhaust not a dual so there is no Y pipe.

Thanks for the suggestions, I will keep working on it and you all will be the first to know if I ever figure out the issue.

 

Diagnosis car problems is having a set proceedure and everytime I have "just known" that that was the problem and skipped diagnostics from the beginning it has always bitten me. Hearing the fuel pump running is one thing all that tells me is that the control circuit is probably OK. I have had instances where the 4" section of fuel line that sits above the pump that connects the output to the fitting that feeds the fuel to the oputside of the tank split... yes, you can hear the pump run. The truck starts but wont accelerate due to insufficient pressure. I had an 05 F150 with multiple cylinder misfires and intermittant poor performance. There is a rubber surge valve just past the pump that smooths out the fuel pulsations from the pump, it had split but had enough spring in it to keep it "kind of" closed. On high demand, inital crank and WOT, the truck would misfire, this was a brand new Ford pump, $600+, you could hear this pump run also. If you test the pump and it isnt the problem then that can be crossed off the list.

 

Update:

Today I did a compression test. As per the FSM, I removed the air intake, disconnected the plug wires from the coil packs, removed all the spark plugs and removed then EFI relay before beginning. For each test I cranked the engine for approximately 6 seconds. The FSM says that this test should be done with the engine warm but that’s not possible due to the truck immediately stalling every time it’s cranked. The FSM calls for minimum pressure in each cylinder to be 127 psi.

First test (Dry)
Cylinder 1: 74 psi
Cylinder 2: 58 psi
Cylinder 3: 88 psi
Cylinder 4: 180 psi

Second test (wet) approximately 0.5-1 oz of oil added to the cylinder through plug hole
Cylinder 1: 90 psi
Cylinder 2: 90 psi
Cylinder 3: 116 psi
Cylinder 4: not conducted due to it being within spec dry

So obviously there is a large issue. I think the head gasket is blown. There is no evidence of coolant mixing with the oil but I’ve heard that isn’t always the case with Toyotas so I will try to get a combustion leak tester/dye in the next couple days to see if combustion gases are leaking into the coolant. If that comes up negative I will start tearing the head down to see if the valves are toast or if the head is cracked.

If you have experience with these kinds of numbers on the compression test and know where to go from here please let me know.

 

Kudos for having enough bravery to find the problem
Many don’t want to do a CT to avoid the bad news…….(me included few yrs ago)

man, those 3cyls are low
Not to pour salt on the wound…..
IMO
I think head has cracks between those cylns (intake/exhaust valves)
Just not making enough compression

I’m no expert, but I have seen multiple threads about cracked 2rz/3rz heads….pictures

do some searching
Everyone here can guide you through this maze NP
Sorry.

 

If you have an air compressor you can preform a cylinder leak down test. Put the cylinder you are testing at TDC compression stroke and with the special tool you put a know amount of air pressure in and the gauge reads the difference. 100 psi on the input side gauge and a reading of 50 on the tool says there is 50% leakage. You listen for air leakage at the oil fill hole, the throttle body and the exhause pipe. If it is at the oil fill hole save the step of removing the head and just pull the motor. Sorry for the bad news.

 

Old School
I Like
Accurate