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Discussion Starter #1
My 87 Milano Stopped Running. Fuel Pump is Working and the Cold Start Injector Works upon Start Cranking. With Starting Fluid sprayed into the intake Plenum, I can tell there is Spark on All Cylinders. BUT, Somehow the injectors have QUIT. Where do I look? Need to find a Sensor, or Sender that "Triggers" the Fuel Injectors on this 3.0 v6,?? help!! (riding my 10 speed now)
 

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Discussion Starter #3
Milano-GTV6 Fuel Injection BUG, Is it the ECU?

Greg's article is great!. There is no mention of a Crank Position Sensor or Cam position Sensor in the GTV6 or MILANO. Where does the Signal Originate to actuate the 6 Fuel Injectors? The I.A.P. Milano Manual References a Hale Effect in the Distributor, But Does not State its Purpose. ( Could that be the Source of the Signal to the fuel Injectors?)
I only am getting Fuel injection from the 7th(Cold Start) injector. Could the ECU have gone bad? The Injector's black wires are Grounded well to the Valve Cover hold down bolts.
 

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milano fuel injection

hall effect sender is in the distributor. the oddly shaped connector on the side of ithe dist is the cable for hall effect. they do go bad. however, it is used to trigger everything, including ignition timing. so, if you are getting spark, i doubt it is the problem.
ecus do go bad as well and the fuel ecu is a separate box... but first, i'd look at the wires and connectors to all the temp sensors, all the grounds, including on the plenum. make sure all are actually solid connections, clean grounds thoroughly.
if not getting values from some of this stuff, the system will not work.
andy
 

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Discussion Starter #5
The Milano has an "Jetronic" ECU ( 0028001 132) under the floor carpet under the passenger footwell. It is the 8 inch metal box with a 1 " cable connecting it to the wiring harness. There is a smaller second box about a foot off the floor where the passenger courtesy foot light is mounted. I think that is for the distributor Spark advance. . Do one of these control Fuel injection? Or is there another control unit somewhere else?
 

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Hi

You wrote

"...Need to find a Sensor, or Sender that "Triggers" the Fuel Injectors on this 3.0 v6...'

The L-Jet systems get their injector signal from the ignition system. So if you have a good spark, that's probably not the problem.

I strongly suspect that you have, either no power going to your L-Jet ECU or no ECU ground. I've dealt with this problem so you can PM me if you want.

There's a wiring diagram of the L - Jet system in then workshop manual Chap 01 page 79. You need this diagram.

The ECU is supplied with power via the Combo relay. The injectors are also supplied with power from the Combo relay. In fact if the Combo relay is working the injectors are always getting 12 V DC postive. The ECU pulses the injectors by turning the ground on and off, via pins 30, 31, 14, 32, 15, and 33.

Howver the first thing you should check is the L-jet system ground on the thermostat. This is G110 on the wiring diagram. It's a black wire that goes from the thermostat body to pin 35 on the ECU. If this ground isn't good then the ECU won't work.

Undo the bolt that secures the wire to the thermostat body, clean them both with sandpaper. Check the ring terminal for damage and then reinstall it.

Finally the cold start injector(CSI) is a free agent. It's not controlled by the ECU or the Combo relay. Tht fact that the CSI is working only tells you that the fuel pressure is good.

Here's some more detail on the injector signal.

Injector Signal

Terminal 1 – Is a low voltage tap off the secondary wiring, it pulses at the same frequency as the coil but at an easy to handle low voltage (12 volts or less). Traditionally this circuit was used to drive the tachometer, and that's what it does on the Milano.

More importantly it runs (via a shielded yellow wire) straight to pin one of the ECU where it constitutes the timing in signal that the ECU uses to generate the injector pulse out, to pins 30, 31, 14, 32, 15, and 33.


Hope this helps.

Bye for now
 

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One thing that you can check quickly is the coolant temperature sender and it's wiring. You will get no injector pulses if it is open circuit
 

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All good things to try. Ignore the ECU for now, those fail very rarely. Check all the grounds first, especially the ones on the passenger side (assuming the car is LHD) that attach to the valve cover near the firewall.

Check your battery voltage, needs to be a minimum of somewhere around 10.5-11v while cranking for the ECU to fire off the injectors.

Also as Ed says, check your Coolant Temp Sensor on the thermostat housing (Greg's article shows you which one).

Your Thermotime sensor seems to be working since your cold start injector is working.

Another common issue is with the combo-relay (double relay) that is attached to the firewall on the passenger side. First check the wires that are going into that connector, some folks have had issues with one or more of those pushing out over time. It is possible that the combo-relay itself could be bad, I've had that happen. A little trickier to test that, easier to pop in another to test it if you know someone close by that has a Milano or GTV6. There is a simplified test procedure in the Milano service manual on page 4-25.

Kevin
 

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The fuel pump requires both of the relays in the combo to be working. The old test of pushing open the flapper in the AFM with the ignition turned on is a comprehensive one. If the fuel pump runs then the combo is good but as you say, it could still be a connection at the relay.
 

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Discussion Starter #10
With ignition on, the injector wires (red or striped) are not showing any Volts there, with voltmeter. ( According to Milanoguy, shouldn't ALL injectors have a One wire always "LIVE", while ONLY the firing injector gets sequentially grounded?) I also noticed the dash warning lites for Oil fuel&Alt are not lighting when you turn on the ignition. Footwell lite not going on when door opens. All Fuses are good, I changed combo relay to another one with no effect. Re-grounded valve cover black wires for injectors and cleaned all thermostat sensors& Wires. (So- I have Spark and cold Start Injector, But 6 non firing injectors. Could some wire on the back of the fuse box making a bad connection?
 

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Discussion Starter #11
Milanoguy: What pin is the Power Input on the ECU?
Pin 35 is the Ground ( good connection) . Pin 1 checked is Where the Yellow Wire attaches which carries the Pulse for the Injectors. This Power source to the ECU could be the Problem
 

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Discussion Starter #12
Injectors are working!!

SOLUTION: DOUBLE RELAY terminals 88b and 88z should have 12 v with the ignition key ON. The 88z 's (red wire) DID. The 88b red wire had NO CURRENT with the key on. I jumped a + charge to 88b terminal directly from the ignition. This restored 12 volts to the 88b (red wire) . ALL the injectors immediately worked!!
There is an open circuit feeding the 88b terminal,(which I bypassed).
Maybe I can trace the open circuit under the dash harness. Meanwhile the Milano Runs!! Thanks MilanoGuy, Barbone 105, Kredden, LaVoce, & alfaparticle!!
 
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