Eng inj fuse repeatedly blowing on RX7
01-30-12, 02:53 PM
#76
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Jumpered the brown and black wires in that connector by the steering column and it did not change the situation.
If a vacuum leak is next then where to check first and how?
Thanks.
01-30-12, 03:11 PM
#77
It's rather hard to check for a vacuum leak when the engine is not running for if it did run you would spray some cleaner here some cleaner there and the sound of the engine will tell you if you found something. Since you cannot get the engine running you would need to create a tool used to hold vacumm at the intake duct and check for leaks. They make these components for rather cheap but perhaps there is still something else you can do in the meantime. You might want to look over the AFM and see if the flapper moves open when pressed upon w/o much resistance. If it is stuck rather closed then it could cause the engine to die out. Also, you might want to disconnect the single plug to the AFM and w/the Circuit Opening Relay jumpered try to start the car. You also want to review the important fuses to see if they are still holding up. These would be the Comp fuse, INJ fuse and the Engine fuse.
01-30-12, 04:12 PM
#78
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It's rather hard to check for a vacuum leak when the engine is not running for if it did run you would spray some cleaner here some cleaner there and the sound of the engine will tell you if you found something. Since you cannot get the engine running you would need to create a tool used to hold vacumm at the intake duct and check for leaks. They make these components for rather cheap but perhaps there is still something else you can do in the meantime. You might want to look over the AFM and see if the flapper moves open when pressed upon w/o much resistance. If it is stuck rather closed then it could cause the engine to die out. Also, you might want to disconnect the single plug to the AFM and w/the Circuit Opening Relay jumpered try to start the car. You also want to review the important fuses to see if they are still holding up. These would be the Comp fuse, INJ fuse and the Engine fuse.
After that I unplugged a big black electrical connector to the AFM.
Again jumpered the brown and black wires under the dash.
THE CAR STARTED!
It ran with LOTS of smoke coming out of the exhaust for a few minutes.
I decided to turn it off and the try again.
On the second attempt I couldn't even get it to initiate the start, it just turned over.
Maybe, it was by chance that these correlated??
Last edited by mszlazak; 01-30-12 at 04:42 PM.
01-30-12, 04:52 PM
#79
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OK, I checked the flapper and it moves easily.
After that I unplugged a big black electrical connector to the AFM.
Again jumpered the brown and black wires under the dash.
THE CAR STARTED!
It ran with LOTS of smoke coming out of the exhaust for a few minutes.
I decided to turn it off and the try again.
On the second attempt I couldn't even get it to initiate the start, it just turned over.
Maybe, it was by chance that these correlated??
After that I unplugged a big black electrical connector to the AFM.
Again jumpered the brown and black wires under the dash.
THE CAR STARTED!
It ran with LOTS of smoke coming out of the exhaust for a few minutes.
I decided to turn it off and the try again.
On the second attempt I couldn't even get it to initiate the start, it just turned over.
Maybe, it was by chance that these correlated??
Battery is getting low and I'm currently recharging.
01-30-12, 06:38 PM
#80
OK, I checked the flapper and it moves easily.
After that I unplugged a big black electrical connector to the AFM.
Again jumpered the brown and black wires under the dash.
THE CAR STARTED!
It ran with LOTS of smoke coming out of the exhaust for a few minutes.
I decided to turn it off and the try again.
On the second attempt I couldn't even get it to initiate the start, it just turned over.
Maybe, it was by chance that these correlated??
After that I unplugged a big black electrical connector to the AFM.
Again jumpered the brown and black wires under the dash.
THE CAR STARTED!
It ran with LOTS of smoke coming out of the exhaust for a few minutes.
I decided to turn it off and the try again.
On the second attempt I couldn't even get it to initiate the start, it just turned over.
Maybe, it was by chance that these correlated??
The smoke was from all the excess fuel being burned off. You have to let the smoke clear off first. You should not have turned the engine off after all the trouble it has had trying to start. Now its probably flooded once again. You tried to out think the car and now you pay the reaper. You need to pull the lower plugs (make sure they are not wet) and disconnect the fuel pump, disconnect the White plug to the leading coil, disconnect the two plugs w/six wires to the trailing coil and then turn the engine over when the battery is charged enough so as to blow the excess fuel out of the rotor housings. Then try to start the car once again. And when it starts let it run followed by letting it run...........................
01-30-12, 09:11 PM
#81
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Nooooooooooooooooooooooooooooooooooooo!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!
The smoke was from all the excess fuel being burned off. You have to let the smoke clear off first. You should not have turned the engine off after all the trouble it has had trying to start. Now its probably flooded once again. You tried to out think the car and now you pay the reaper. You need to pull the lower plugs (make sure they are not wet) and disconnect the fuel pump, disconnect the White plug to the leading coil, disconnect the two plugs w/six wires to the trailing coil and then turn the engine over when the battery is charged enough so as to blow the excess fuel out of the rotor housings. Then try to start the car once again. And when it starts let it run followed by letting it run...........................
The smoke was from all the excess fuel being burned off. You have to let the smoke clear off first. You should not have turned the engine off after all the trouble it has had trying to start. Now its probably flooded once again. You tried to out think the car and now you pay the reaper. You need to pull the lower plugs (make sure they are not wet) and disconnect the fuel pump, disconnect the White plug to the leading coil, disconnect the two plugs w/six wires to the trailing coil and then turn the engine over when the battery is charged enough so as to blow the excess fuel out of the rotor housings. Then try to start the car once again. And when it starts let it run followed by letting it run...........................
We do learn by our mistakes
So I basically did everything OK but stopped to soon.
OK, so what about that AFM connector and jumping the brown and black wires under the steering column?
Do that again then let it run out and then connect things up afterward? That's what I did previously when trying to start again.
Satch, thanks for the guidance and patience, it's much appreciated.
01-30-12, 09:31 PM
#82
You might have some interference from the AFM for this or that reason so you should check some of the pins at the ECU which relates to it. Pin 2E should read 4 volts w/key to on. Pin 2J reads 2 to 3 volts when the air temp is 68 degrees (this reading is less important than the first one).
The jumper at the relay is to take the place of one of the roles of the AFM and it causes fuel to flow w/key to on so you don't really want to leave the key in the on position more than necessary to prevent flooding. You can also look in the FSM in section 4A page 54 for the procedure to test the AFM.
Since your only start occurred w/o the AFM I would try it again to get the car running so it could idle and burn off the excess fuel and in the meantime check the AFM according to spec. The AFM does have a Brown wire as part of the Emission harness and possibly this is one of the wires that was damaged. Could it be playing a role in the whole scheme of things? Can't really tell at this point.
The jumper at the relay is to take the place of one of the roles of the AFM and it causes fuel to flow w/key to on so you don't really want to leave the key in the on position more than necessary to prevent flooding. You can also look in the FSM in section 4A page 54 for the procedure to test the AFM.
Since your only start occurred w/o the AFM I would try it again to get the car running so it could idle and burn off the excess fuel and in the meantime check the AFM according to spec. The AFM does have a Brown wire as part of the Emission harness and possibly this is one of the wires that was damaged. Could it be playing a role in the whole scheme of things? Can't really tell at this point.
01-30-12, 10:01 PM
#83
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You might have some interference from the AFM for this or that reason so you should check some of the pins at the ECU which relates to it. Pin 2E should read 4 volts w/key to on. Pin 2J reads 2 to 3 volts when the air temp is 68 degrees (this reading is less important than the first one).
The jumper at the relay is to take the place of one of the roles of the AFM and it causes fuel to flow w/key to on so you don't really want to leave the key in the on position more than necessary to prevent flooding. You can also look in the FSM in section 4A page 54 for the procedure to test the AFM.
Since your only start occurred w/o the AFM I would try it again to get the car running so it could idle and burn off the excess fuel and in the meantime check the AFM according to spec. The AFM does have a Brown wire as part of the Emission harness and possibly this is one of the wires that was damaged. Could it be playing a role in the whole scheme of things? Can't really tell at this point.
The jumper at the relay is to take the place of one of the roles of the AFM and it causes fuel to flow w/key to on so you don't really want to leave the key in the on position more than necessary to prevent flooding. You can also look in the FSM in section 4A page 54 for the procedure to test the AFM.
Since your only start occurred w/o the AFM I would try it again to get the car running so it could idle and burn off the excess fuel and in the meantime check the AFM according to spec. The AFM does have a Brown wire as part of the Emission harness and possibly this is one of the wires that was damaged. Could it be playing a role in the whole scheme of things? Can't really tell at this point.
Thanks.
Last edited by mszlazak; 01-30-12 at 10:05 PM.
01-31-12, 12:26 AM
#85
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Did everything you suggested to de-flood and the car runs.
In fact it started running with little smoke.
However, as things went on and the car eventually got to running temperatures hotter than normal, the smoke progressively seemed to be getting worse. It even seemed to also be coming up in the engine compartment from behind the fuel injector and not just out the tail pipes. Maybe it drifted from the pipes ... but that would be a second guess.
The car eventually stalled as the idle dropped low enough.
I restarted it two more times, smoke was still present and it stalled when rpm dropped low enough.
After all that I checked readings at pin 2E w/key on, jumper removed, & connector replaced at AFM. 2E reads 4 volts.
However, I decided to take a reading at 2I again and it read 0.6 volts!
In fact it started running with little smoke.
However, as things went on and the car eventually got to running temperatures hotter than normal, the smoke progressively seemed to be getting worse. It even seemed to also be coming up in the engine compartment from behind the fuel injector and not just out the tail pipes. Maybe it drifted from the pipes ... but that would be a second guess.
The car eventually stalled as the idle dropped low enough.
I restarted it two more times, smoke was still present and it stalled when rpm dropped low enough.
After all that I checked readings at pin 2E w/key on, jumper removed, & connector replaced at AFM. 2E reads 4 volts.
However, I decided to take a reading at 2I again and it read 0.6 volts!
Last edited by mszlazak; 01-31-12 at 12:28 AM.
01-31-12, 08:35 AM
#86
Pin 2I, Water Thermosensor, should drop to about .5 volts as the engine finally heats up so that is a proper reading you have. You should test the AFM according to the FSM and if it checks out properly then try to start the car w/it connected up. It was good for you just to get the car started but running the car w/o the AFM causes the car to run fairly rich I think so that would perhaps explain why it eventually bogged down in addition to the fair amount of smoke.
02-02-12, 08:46 PM
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Pin 2I, Water Thermosensor, should drop to about .5 volts as the engine finally heats up so that is a proper reading you have. You should test the AFM according to the FSM and if it checks out properly then try to start the car w/it connected up. It was good for you just to get the car started but running the car w/o the AFM causes the car to run fairly rich I think so that would perhaps explain why it eventually bogged down in addition to the fair amount of smoke.
Thanks again for all the help Satch, it was much appreciated.
08-20-12, 03:38 AM
#88
if the 15 amp Engine fuse (interior fuse box) is blown, will that cause the "eng inj" fuse to blow
or am i still looking at a grounding issue with the "Eng Inj" fuse?
08-20-12, 07:15 AM
#89
Assuming you have an S4, the INJ fuse has a Black/Green wire coming from it that connects to the Main relay at the 4 wire relay plug. When does the fuse blow? Is it when trying to start the car or just sitting there after you replace the fuse? Since the fuse has a Black/Green wire connected to it you can isolate this section of wiring to see if a resistance test gives you any clues. The wire runs from the fuse to the 4 wire Main Relay plug. Disconnect the plug from the relay and w/the fuse pulled from the engine fuse box take a resistance reading on this wire and see if it is abnormally high. If it tests out normal then the problem is likely after the relay but before either the coils or injectors. If the 15 amp Engine fuse was pulled and the INJ fuse continued to blow then the problem is occuring at a point before the Main Relay.
Last edited by satch; 08-20-12 at 07:26 AM.
08-21-12, 03:27 AM
#90
Thanks satch, yeah S4
it had been blowing as soon as i turned it on reds
i disconnected the relay, it didnt blow this time
definitely after the relay somewhere.. its doing my head in
it had been blowing as soon as i turned it on reds
i disconnected the relay, it didnt blow this time
definitely after the relay somewhere.. its doing my head in
08-21-12, 07:47 AM
#91
You can bypass the relay by jumpering the Black/Green wire to the Black/Yellow wire and see if that causes the fuse to blow or not. You could also jumper the White/Blue wire to Black/White and attempt to start the car if the fuse does not blow when the respective wires are jumpered. If the car is able to start and run w/o the fuse blowing then there is a problem w/the relay. Jumpering these wires could drain the battery when the car is not in use so this is just a temporary jumpering to help diagnose things. If the fuse blows when jumpered then the wires running to the coils and injectors would be suspect. Doing a resistance test on these wires would indicate where the short is. Also, the injector wires run to one of the large Orange connectors near the ECU before being routed to the injectors. If you believe it is the injector wiring causing the short then you can disconnect the necessary plug and narrow down the short as being before or after the Orange connector.
08-22-12, 05:38 AM
#92
what readings should i get when i do the resistance test on the injectors and coils?
also i should have mentioned i am running individual coil packs
and a microtech lt10.
I think the big orange wire might be a different colour..?
also i should have mentioned i am running individual coil packs
and a microtech lt10.
I think the big orange wire might be a different colour..?
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