No Injector Pulse EJ22 1992 Leg Wag

[GRANDLOYALE]

Hello,

 

I have a 1992 Legacy Wagon, EJ22, AWD.  A few days ago the motor would not fire up and has not fired up since.

 

The wagon has not had any motor work done to it for over 3 years.  It ran and drove great over these past 3 years.  The wagon has never been in an accident.  The timming belt was replaced 3 years ago.

 

What I've checked:

-Fuses (both under the hood and Under the dash)

-Ran the codes (24, 11, 13)

-Inspected crankshaft position sensor.  Tested sensor and found it to be working and within spec.

-Inspected camshaft  position sensor.  Tested sensor and found it to be working and within spec.

-Swapped out both sensors with known working ones just to be sure - no change in problem.

 

  ALSO did this test

- disconnected crank sensor, connected cam sensor, sprayed fuel into intake, turned over motor, no run

- disconnected cam sensor, connected crank sensor, sprayed fuel, turned over motor, no run.

- connected both sensors, sprayed fuel, turned motor over - runs like a frickin champ.

 

*** Cant test the Air Control Valve (code 24) because the Haynes manual does not have that part listed in the book.

 

-Inspected Coil, All plugs are getting spark and sparking properly when the motor is turned over.

-Inspected Fuel Filter.  Good volume of fuel flows through filter.

-Fuel Pump.  I did not have the proper gauge to test fuel pressure, so I replaced the fuel pump with a brand new pump.  Fuel filter sock is new to.

-Tested fuel injectors, all 4 have proper ohm reading.

 

What I've discovered is the fuel injectors are not pulsing. 

 

-I tested each electrical lead and found that there is no power getting to any of the injectors.  When I switch the key on, I should have 12V.

 

I dont know what else to look at. 

 

Any suggestions?

 

Thanks.

[GRANDLOYALE]

UPDATE:

 

#1. Discovered that the voltage meter I was using had a bad battery and was not accurate.  

 

NOW, I register only 3V at each injector.

 

- Removed ECM and installed it into a Good Running Leagcy of the same vintage.  Good Legacy ran fine.  ECM is OK

- Removed Crank sensor from bad wagon and installed into Good Running Legacy.  Good Legacy ran fine.

- Removed Cam sensor from bad wagon and installed into Good Running Legacy.  Good Legacy ran fine.

 

Tested Air Control Valve on Good Running Legacy, then compared with the bad wagon.  Bad Wagon's Air Control Valve had same readings, so I assume it is good.

 

Good Running Legacy has 10.5V at each injector.  When the motor is running the voltage increases to 11.5V.

 

Bad Wagon only has 3V at each Injector.  When the motor is turned over the voltage drops to 2V.

 

Thats all I know at the time.

[1 Lucky Texan]

is the big hose from the IACV connected under the intake tubing?

 

I would pull the covers and check timing.

 

I'd say possibly a bad ECU ?

Edited May 9, 2016 by 1 Lucky Texan

[GRANDLOYALE]

is the big hose from the IACV connected under the intake tubing?

 

I would pull the covers and check timing.

 

I'd say possibly a bad ECU ?

Thank you for the reply.

 

The big hose is connected.

 

Dont need to check the timing marks, because when I spray starter fluid into the intake manifold, the motor will run perfectly.  

 

I check the ECU.  I removed the ECU from the non running wagaon (1992) and installed it into a running wagon (1994).  The ECU worked perfect in the 94.  So the ECU is fine.

 

Thanks for your suggestions.

[mikaleda]

Inspect the connecters to the motor by the battery I've accidently dislodged them before changing a battery. Its kind of a long shot, but is the only thing I can think of that would cause this issue.

[1 Lucky Texan]

is it possible the gas is bad? water in it or a vindictive neighbor sabotaged the car?

 

maybe try some HEET?

[GRANDLOYALE]

Inspect the connecters to the motor by the battery I've accidently dislodged them before changing a battery. Its kind of a long shot, but is the only thing I can think of that would cause this issue.

I did look at this and press both block together.  Thanks for the idea.

[GRANDLOYALE]

is it possible the gas is bad? water in it or a vindictive neighbor sabotaged the car?

 

maybe try some HEET?

 

I dont think this is the issue either.  When we had the fuel pump out, we looked at the tank and it looks brand new.  I saw no funky pools or puddles of water at the bottom or top of the tank.

 

Also, I'm not getting any fuel into the combustion chamber at all.  I can crank and crank, then pull the plugs - they are dry - sniff the exhaust pipe - no fumy gas odors of any kind.  

 

I'll post some pics in a minute.

[GRANDLOYALE]

So, we have checked many things on the 92 wagon which wont start.  We've compared those findings with the 94 which does run.

 

When we measured volts at the injector plug, we found that the 92 was different than the 94.

 

Here is a graphic showing you the electrical plug which connects to the injector.  

 

We read the voltage in three ways - Key in Run Position,

1 - Placed the (+) & (-) lead on each electrode [bLUE READING] at top of graphic - 10.3 volts

2 - Placed the (+) on the left electrode and (-) to ground [GREEN READING] - 12 volts

3 - Placed the (+) on the right electrode and (-) to ground [RED READING] - .02V

 

We assume this is normal.

 

Here is what we got with the 92 Legacy wagon with no Fuel Injector Pulse.

 

As you can see test number there is a difference in the readings.

 

1 - [bLUE] 92 Legacy only reads 3.3V compared to the 10.3V of the 94 runner.

2 - [GREEN] 92 Legacy reads 12V just like the 94 runner.

3 - [RED] 92 Legacy reads 9.5V compared to the 0 volts of the 94 runner.

 

I dont know what is causing this variation in the 92.  We think it might be something to do with the ground.  

 

There are some more tests that we have read about and will try them next.  

 

Hopefully we will be able to find a solution to this mystery and in turn, get the motor to run again.

 

Any suggestions or similar stories are welcome here, something might connect.

Edited May 12, 2016 by GRANDLOYALE

[GRANDLOYALE]

Bump to top.

 

I'd love some feed back, I'm at a dead end.

[Crazyeights]

Try checking all of the ECM grounds.

[mikaleda]

It definitely seems to be some sort of grounding issue, I would check all grounding points under hood and under the dash.

Edited May 22, 2016 by mikaleda

[Fairtax4me]

Injectors share common power.

ECU grounds the injectors separately which makes them spray.

 

The main engine harness has three plugs on the front left side of the engine. I would check inside those first. The largest is the one with the injector grounds IIRC, and also carries the ground wires for the ECU. Corrosion there could create high resistance and cause your lack of ground, though it would more likely affect only one injector.

It could also be a poor connection of the engine harness ground which is bolted to the back of the number 4 intake runner. It's down low near the junction for the fuel supply line from the fuel rail.

Edited May 23, 2016 by Fairtax4me