Cranks, but no start 08 Tacoma 2.7L 5 lug base model

Hello

I'm helping a friend with his Tacoma, and I need some help. Here is the story I was told. The truck wouldn't start, so he had the fuel pump replaced. It still wouldn't start. The mechanic gave up on it and told him he could not fix it.

No CEL, and my scan tool can't connect to ECM

This is what I have done so far:
Charged Battery just to be sure
Checked all fuses in both locations and tested for voltage
Checked and swapped relays around
Pulled fuel tank and checked connections
I tried spraying starting fluid to test for ignition (Didn't start or even try to start)
It's the 5 lug base model, so I don't think it has the immobilizer (The light never comes on and he was using an aftermarket key with no chip (I even got the original key and tried that)
New plug & play ECM, (scan tool still can't connect)
Jumped the OBD pins for 30mins to reset everything (per youtube videos)
New OE Denso Crankshaft sensor

I'm completely stumped!

I've searched and read a lot of posts on here, but haven't found a solution.

Thanks,
JR

 

If you have no CEL with the key on and can't communicate with the PCM you could have:

A power or ground feed problem at the PCM.
A problem with the CAN network (unlikely to cause a no start and no CEL).
A shorted 5v Ref circuit.
A wiring problem.
A bad PCM.

I'd start with checking all powers and grounds at the PCM with a test light just be careful that you don't spread the pins in the connectors.

 

Thank you Sir! I will start checking everything out

 

Did it start with starting fluid or not?

I assume it did not.

I too would begin by checking power to the ECM.

The US 2.7 liter Tacoma's do not have an Immobilizer System and doesn't have or need a chipped key.

 

No, it did not start

 

So was the truck running fine then one day would not start?

 

Check pin 16 on the OBD port for voltage as well as all the ECU voltages and grounds.

What OBD scanner are you using? Something like a scan gauge or a wireless and using an app? If it is a wireless does it light up when you turn the key on as mine does?

 

Yes

 

Have you checked for spark?

 

Pin 16 has 12v, OBD Link MX+, it lights up

 

Have you gotten around to checking powers and grounds at the PCM yet?

 

As mentioned, check your spark and electical.

Also what happened when you sprayed fuel? any stutter? I'm getting at the fuel filter/fuel line may be clogged but seems unlikely.

 

I'm about to start on that right now

 

Check your fuel pressure and with nothing to lose, pull the starter and battery and go have both loaded tested.

 

The pins with the red circles have 12v with the key on. Pin 3 (brown wire) does not have any power with key on or off. Is pin 3 supposed to be 12 battery (always on) according to the ECM pinout?

 

Brown wire looks like it should be a ground according to the wiring diagram.

 

I'm having trouble understanding what connector pins to look for. In the red circled area, I would look for Connector E4 pin 3. Is that correct?

 

Yea, Mitchel must have something screwy with their pinouts because I looked on both wiring diagrams (06 OE and 08 Mitchel redrawn) and connector e4 pin3 brown goes to a ground at the rear of the cylinder head.

 

I have the 06 FSM on my PC at home I'll have to see what the pinouts show on there when I get home.

 

Thanks, I appreciate it