subpennyman Posted December 28, 2004 Share Posted December 28, 2004 If an injector can prime the sbfi, does that mean the injector is ok? Quote Link to comment Share on other sites More sharing options...
WJM Posted December 28, 2004 Share Posted December 28, 2004 is the fuel pump running and getting power? Quote Link to comment Share on other sites More sharing options...
subpennyman Posted December 28, 2004 Author Share Posted December 28, 2004 Yes, I can hear it. And all fuses are good. Quote Link to comment Share on other sites More sharing options...
Cougar Posted December 28, 2004 Share Posted December 28, 2004 Subpennyman, Did you read my last post to you on this in the other thread? Here is a copy of it in case you missed it: Yes, a scope would be better to see the pulses. It's just that not many people have one on hand or know how to use one so I didn't think about it. By all means use it if you would like to. You shouldn't need to have the injector tied to the lead to watch for the pulses. Since I don't know what the second set of higher resistance leads are for I thought it may be good to leave them in the circuit. Having them disconnected may change the test results. It sounds though that the ECU is not generating the pulses to open the injector. I think the ECU makes a ground connection to turn on the injector. The ECU needs to see the ignition pulses from the distributor to do this I believe. It may also need to see the signal from the crank angle sensor. I'm not sure what lead carries the ignition signal to the ECU but you may be able to find it using the ohmmeter. It would also be good to check the crank angle sensor signal also. The sensor is located near the flywheel I think. Quote Link to comment Share on other sites More sharing options...
Cougar Posted December 28, 2004 Share Posted December 28, 2004 You may be able to prove out the injector by tieing a resistor to the connection that runs back to the ECU for the ground connection. I would guess using around a 10 ohm resistor may work. Touching the other end of the resistor to ground should make the injector turn on if the resistor value is not too large. If you are not seeing drive signal pulses at the injector though you will still need to check other signals and votages at the ECU. Something is missing. I would check the CAS and the ignition signals going to the ECU as I mentioned earlier. As another poster mentioned, it may be beneficial to go to your local library and see if you can get a copy of a wiring diagram for your model car. This kind of problem is one of the most difficult to troubleshoot I know of for these cars, since it requires input from other areas to the ECU to make the injector work. Quote Link to comment Share on other sites More sharing options...
subpennyman Posted December 29, 2004 Author Share Posted December 29, 2004 With the Coil disconnected, I can look down the throat of the throttle body and see the injector consistently squirting fuel. The moment I connect the coil- the car starts and dies when all the fuel is burned up! Something is telling my ECU to turn off the injector! What devices have the capability to tell my ECU to kill the injector and how can I bypass these devices to narrow things down? Does anyone have a wiring diagram/schematic for a 93 Loyale Wagon/manual trans? Or a link to one? If so please contact me through this board or directly by e-mail scottyd9@nventure.com. Cougar- I appreciate all of your help. Sub. Quote Link to comment Share on other sites More sharing options...
Skip Posted December 29, 2004 Share Posted December 29, 2004 Scotty, One of the main components to the engine running is the MAF. It is on the air filter box and connected to the engine via the intake tube / plenum. You do NOT mention replacing the intake plenum any time you run these tests. The ECU will see no air flow and may not deliver fuel if it is not connected when the key is in the "run" position. The other main component in the firing of the injector is the crank angle sensor as Cougar pointed out. This unit is inside the distributor (it is the firing signal for the injector and for the spark) Gentle warning here - please do not start another post just do a continuation of the original. People that may want to help need the information. Quote Link to comment Share on other sites More sharing options...
subpennyman Posted December 29, 2004 Author Share Posted December 29, 2004 Skip, Thanks for all your words of wisdom. In the history of troubleshooting this problem, I was able to get the engine to run with the MAF assy diconnected from the throttle body-ie the engine was running but no airflow was going through the MAF. I also have tried to run the engine with the MAF disconnected- whether it is connected or disconnected, it failed to stay running. Also the device under the cap appears to be working because my injector is pumping fuel with the coil center wire disconnected. Sub. Quote Link to comment Share on other sites More sharing options...
Skip Posted December 29, 2004 Share Posted December 29, 2004 Sub, In all fairness the ECUs in these cars are very dependable. The next on my list of trials in your case would be to find someone on the board with a spare SPFI ECU and try it. Do you know what a "noid" is? FI noids -$11.00 It will tell you if the injector is quiting as It is still a possibility that the fuel pump shuts down - you do know the fuel pump control is tied into the seat belt system don't you? But you say you can see it shut down - the intake plenum must be removed. So let me get this straight You have the engine cranking over to start You look down the TB and see gas being injected You connect the coil primary side???? The engine fires - you release the key to the "run" position The engine runs for a short time and dies. Is this correct? The info on the system operating with the MAF disconnected is some what confusing. I have seen them run for several seconds (possibly 10 ) and then shut down. I am very sorry I should keep me cake hole shut. I own no SPFI cars - all of mine are carbed or hot wire MPFI. I have only worked on several of these beasts. Quote Link to comment Share on other sites More sharing options...
subpennyman Posted December 30, 2004 Author Share Posted December 30, 2004 Skip: So let me get this straight You have the engine cranking over to start You look down the TB and see gas being injected You connect the coil primary side???? The engine fires - you release the key to the "run" position The engine runs for a short time and dies. Is this correct? Almost.... I stop cranking-reconnect the center wire to the Cap- crank it again- it starts and runs for about 4 to 5 seconds and then dies- pumpiong the accelerator does nothing other than add more air to the mixture. Normally; upon cranking the car will start and run for 1-2 seconds and then die. If I chose to inject gasoline or starting fluid down the throat of the spfi after it is running- it will stay running as long as I give it fuel. Last week.... I disconnected the 4 pin connector(valve position sensor) at the SPFI body and attempted to take voltage measurements- 2 pair had approx 6 volts dc each. Not knowing what specifically to do with the information or where to go from here, I decided to put everything back together and go inside and think about it! But before I closed the hood, I tried to start it one last time- the thing started and stayed running! It was very rough- and thats when I realized I had never tuned it up since we bought it new-it has 155,000 on it. Well, I tuned it, plugs, wires, cap, rotor, air filter (it was plugged pretty good)! And the gap on the plugs was easily .88 twice of what the spec calls for. After the Tune Up, I am now back to my original problem! It starts and then dies! I had never heard of the NOID- Thanks for the info. I also tried the car with the seat belt and shoulder harness plugged in- no change. Sub. Quote Link to comment Share on other sites More sharing options...
Cougar Posted December 30, 2004 Share Posted December 30, 2004 After going over the newer posts am I understanding correctly that the motor seems to die after the key is released to the run positon and the residule fuel is exhausted? Edit: With regards to the following paragraph. After looking at my manual again I noticed that this lead is in the 'start' position and not the 'run' position as I first thought. My manual for an '88 shows a wire coming from the ignition switch that supplies power to the SPFI control unit through a 15 amp fuse #20, in the run position. If your car has the same setup, and if the ignition switch contacts are bad, then perhaps the SPFI unit is not getting power while in the run position. The lead from the fuse ties to pin 18 of the SPFI unit. You could try checking that pin and see if you have 12 volts there while cranking. If so, and the voltage drops out while the key is released then I think that this is the problem. Quote Link to comment Share on other sites More sharing options...
Cougar Posted December 30, 2004 Share Posted December 30, 2004 Skip, The injector for Subpennyman's Loyale has two pairs of wires going to it. One set measured about 0.5 ohms. I assume this is the coil to open the injector. The other set on contacts showed about 4.5K ohms. I have no idea what the other set of leads is for unless it provides some sort of feedback to the control unit. Any revelations on this? Quote Link to comment Share on other sites More sharing options...
subpennyman Posted December 30, 2004 Author Share Posted December 30, 2004 Skip- Not so - That is the Valve positioner 4 wires! My mistake. The injector has 2 wires that are soldered on right smack in the middle of the SPFI Throttle Body! GLEN- Also, the car will run after the key is released if starting fluid or additional fuel is poured down the throat of the SPFI! Sub. Quote Link to comment Share on other sites More sharing options...
Skip Posted December 30, 2004 Share Posted December 30, 2004 humor me on this one add a can of dry gas to the fuel tank remove the electrical plug on the MAF. run the same test where you see the fuel come out of the injector replace the plug into the MAF connect the MAF hose to the throttle body connect the coil wire start the engine and see if you can hold the throttle at around 2000 RPM print this procedure if ness. Quote Link to comment Share on other sites More sharing options...
Cougar Posted December 30, 2004 Share Posted December 30, 2004 Yes, I understand. The way I understand things is the injector seems to let fuel in while in the start position but is cutoff somehow in the run position. Correct? Everything else seems fine as it will run if fuel is supplied to the engine. It really would help to have the exact diagram for this engine. I may try going to the library if I have time, to research this. Something is turning off the SPFI control unit it appears to me. It could be a defective unit and it may be worth doing a swap with a known good one to see if things will work then; if you can get one from somewhere at a reasonable price. Thanks for the correction about the injector wire hookup. I had not heard of 4 wires to the injector before. Quote Link to comment Share on other sites More sharing options...
subpennyman Posted December 31, 2004 Author Share Posted December 31, 2004 Skip-What is a can of dry gas? Where do i find it and how many gallons do I add to my 1/2 full Loyale Tank? Cougar- That is exactly correct! I wonder if I should try try disconnecting the starter-rather than letting go of the key? I dont know exactly where to get another SPFI on a barrow basis. Would you? Sub. Quote Link to comment Share on other sites More sharing options...
Cougar Posted December 31, 2004 Share Posted December 31, 2004 Dry gas is methenol and is used to absorb water in the fuel. I think Skip is trying to eliminate that as a possibility for this problem. Most service stations will have this or auto stores. If you want to try a different control unit you may be able to find one at a locale salvage yard for a reasonable price. Since the control unit is having trouble running with the ignition switch in the run position I would see if you can find a problem with the switch. Maybe a connection is not making contact while in the run position. If you haven't checked the fusible links for a problem it might be good to do so. They may be in a black plastic box mounted on the coolant reservoir. That is the way my '88 was. Quote Link to comment Share on other sites More sharing options...
royboy159 Posted January 22, 2005 Share Posted January 22, 2005 This thread continues at:http://www.ultimatesubaru.org/forum/showthread.php?t=28753 Quote Link to comment Share on other sites More sharing options...
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