2LTE EFI Troubleshooting (1 Viewer)

[Tristan Perry]

Hi all, having a bit of a rough time and thought I'd reach out with some of my experiences.

Truck ran great, no problems starting, no problems overheating. Stopped for groceries and 10 minutes ater she just would not start. Messed around bleeding injectors for some time before towing home. (Thanks BCAA). Note: when I initially lifted the hood I found my racor filter empty, hmm..

Once home I got everything primed upto the pump well, good head pressure. And after ages of priming and cranking, the injection pump was only sending a little fuel to #1 & 2 injectors. I have clear fuel lines installed, and could see no fuel returning from the pump. Tear the pump off and send it to fred Holmes along with the injectors. FH finds all three sensors in the pump are bad and presents a $2400 repair estimate.

I bought a pump off a running engine from a friend, tested all the electronics to find no faults and installed it along with rebuilt injectors and hot tanked high pressure lines. New timing belt, oil pump gasket, and water pump, etc as well. Engine spins over by hand nicely, all timing Mark's are consistently lining up. All installed and primed, the IP is returning fuel on manual priming alone, all good signs.

On cranking with the starter, the engine is spinning freely and making good compression, but will not try to start. Not even the slightest bite or tick. It will almost run on starting fluid, but it does not sound like any fueling is happening. Cracking the new injectors shows fuel there, but maybe not enough volume/pressure as before. Cracked nozzle nuts dont lead to spraying fuel like it would under normal running condition.

Back to the diagnostic port; i got code 5 and 11:
-code 5 turned out to be a shotty connection on one of the resistor connectors, fixed and cleared
-code 11 persists...

Regarding code 11 I have read it can he tied to the TPS. I have tested the tps through the obd port to find ok values, and did the bench testing, all OK.

My inclination now is this code 11 is preventing proper runtime volume/pressure due to a fault in the park/neutral switch. (Starter engagement is not locked out, and I've tried starting in both park and neutral.) Everything I've found online related to this code 11 problem with a badly running engine, not a no start like mine.

I've found via manuals that on the ECU connector, there is a terminal NSW that has 12v on the park/neutral condition from an inhibitor somewhere. This will be my next area of investigation. (Anyone found this?)

Can anyone offer any tips, pointers, or suggestions on this?

All appreciated, thanks!

 

[GTSSportCoupe]

Just a simple thing to try: check your grounds from the battery to chassis. There is one ground in particular from the battery to the rad/grill support (or whatever is just in front of the battery) that I can tell you will cause the symptoms you're having. I've been there myself; exactly the same symptoms. Make sure it is a very clean good tight electrical connection. Maybe use some emery cloth/wire brush to clean it all up. Maybe it'll make the difference?

 

[Tristan Perry]

Thanks mate. I believe I have narrowed it down to a problem within the ecu.

My ecu is part 89661-60111, for vehicles built 1990/07 - 1991/08.

I have found readily avaliable replacements of the previous year's ecu, part 89661-60110, produced 1990/04-1990/07.

My question is now if you or anyone knows if I can fit an a/t ecu from the previous production year with success?

Thanks in advance

Just a simple thing to try: check your grounds from the battery to chassis. There is one ground in particular from the battery to the rad/grill support (or whatever is just in front of the battery) that I can tell you will cause the symptoms you're having. I've been there myself; exactly the same symptoms. Make sure it is a very clean good tight electrical connection. Maybe use some emery cloth/wire brush to clean it all up. Maybe it'll make the difference?

 

[Tristan Perry]

Hey there,

I've confirmed all grounds, and also swapped in a known to be good ECU. Still no start.

Still getting very low fuel delivery pressure at the injector. When the pipe is disconnected, it's just dripping out of the pipe when cranking.

Feeling very much at the end of my rope after replacing the injection pump, rebuilding injector nozzles, and now replacing the ecu.

The onboard diagnostics are also giving a 'normal' indication for insult to injury.

Any help greatly appreciated, thanks!

 

[roscoFJ73]

Note: when I initially lifted the hood I found my racor filter empty, hmm..

I think you should have paid more attention to your own observations. The problem may be in the fuel delivery from the tank. I didn't see any mention of it.
Filters going empty are a classic air leak symptom as the fuels flows back to the tank.

 

[GTSSportCoupe]

I think you should have paid more attention to your own observations. The problem may be in the fuel delivery from the tank. I didn't see any mention of it.
Filters going empty are a classic air leak symptom as the fuels flows back to the tank.

Exactly what I was thinking too when I re-read that in his post.

 

[roscoFJ73]

Bad inj pumps dont usually empty the fuel filter.