Injectors not firing; crank / no start

[surfin cj7]

Hello everybody,

History:

I helped my buddy purchase an 1987 4Runner with a 22re that has ~165,000 miles about a month back and we have been trying to get the rig running. The previous owner thought he had a head gasket issue so he replaced the head gasket but in the process stripped a bolt on the lower intake manifold where one of the coolant lines is connected.
We replaced the intake manifold and started it up and let it run for a few minutes. We shut it off to check the coolant and oil levels and found that the "milk shake" had appeared. Long story short the guides were broken on the timing chain so we replaced the timing chain cover, chain, guides, etc. and tried to start it up and now it will only crank but not start. I have searched and used other threads and FSM to conduct troubleshooting and based on that troubleshooting below I believe the fuel injectors are not getting the ground signal from the ECU and the cold start injector is not getting the right signal but have not been able to fix it.

Completed troubleshooting:

Spark/timing
- I get good spark at the plugs when cranking the engine (grounded to block)
- I have verified TDC, made sure the timing mark was at zero and the rotor was pointing at 11:30. atleast 5 times.
- I have double checked the wiring & firing order
- 175 psi compression on all four cylinders

Air
- I have checked the voltages & resistances listed for the AFM and all within spec
- the intake tube is in good shape
- all vacuum hoses connected and in okay shape

Fuel
- Fuel pump is heard when key is in "on"
- Fuel pressure is 38 psi after fuel filter going to fuel rail.
- Fuel injectors and cold start injector "fire" when battery power and ground applied to terminal.
- Truck starts and runs until starting fluid burns off when starting fluid sprayed into CSI hole

Electrical
- All fuses checked and looked good
- New EFI main relay installed
- New Circuit Opening Relay
- Solenoid resistor checked, input and output voltages within spec
- known working ecu swapped in
- dedicated ground from fuel injector harness to neg battery ran (ground normally connects to manifold)
- same voltage out of solenoid resistor to fuel injector connectors (not a splice issue then?)

ECU checks (per FSM)
- voltage in specs at +B - E1
- voltage in specs at BATT - E1
- voltage in specs at IDL - E2
- voltage in specs at Vcc - E2
- voltage in specs at VTA - E2 with throttle valve closed
- voltage not in spec at VTA - E2 with throttle valve fully open
- voltage in specs at STA - E1
- voltage in specs at No. 10 - E01 & No. 20 -E02
- voltage in specs at Vc - E2
- voltage in specs at Vs - E2 with measure plate fully open & closed
- voltage in specs THA - E2

I could not do any voltage checks that were done at idle obviously and didn't check coolant temperature voltage.

Things left to do/check:

The ECU is giving fault codes 4 & 11.

4 = TPS sensor fault
11 = coolant temperature

I am going to get a new TPS sensor and have another coolant sensor to install.

Again, it appears that the injectors have the correct voltage but are not receiving the "ground" signal to fire. Also the cold start injector is not firing.

Any suggestions for additional tests or checks would be appreciated. We want to get this puppy running soon b/c the temporary registration is about to expire.

Thanks,
Matt

 

[SV_Dude]

Depending on how bad your TPS is, that will stop your engine from starting.

What makes you think that your injectors aren't firing? Since you have the FSM, check the pinout on the ECU and do a continuity test between each injector and the pins on the ECU. As long as the connection is good then that would rule out your injectors.

My bet is your TPS. Your temp sensor won't stop your motor from running but it will give you bad mileage and possibly make your motor run bad.

Check the adjustment on your TPS before you decide that you need to spend $100 on a new one. Sometimes the TPS spring just wears out and you need to adjust it.

 

[KidVermicious]

My bet is your TPS. Your temp sensor won't stop your motor from running but it will give you bad mileage and possibly make your motor run bad.

Check the adjustment on your TPS before you decide that you need to spend $100 on a new one. Sometimes the TPS spring just wears out and you need to adjust it.

I concur with this. A poorly adjusted TPS can do all sorts of funny things. I'd check the one you've got before replacing it, and if it passes all your tests you'll know it's good and doesn't need replaced at all.

Toyota 22RE Throttle Position Sensor