No spark after injector swap. PLEASE READ

[2g 6 bolt swap]

For the past 4 days i have been trying to figure out a problem that start after an injector swap. The first thing i did was disconnected the fuel pump to clear the line of gas, but i didnt realize when i did that i still had the key on. I was not sure if that could be part the problem i have having now but after i touched the clip on the fuel pump my car no longer got spark. So my mpi relay are both good. Got a click from both relays inside of the gold box. Fuel pump relay also clicks when i turn the key. Would the relays on top of the interior fuse box have anything to do with my car not having spark?

 

[dave99gst]

the CAS would have somthing to do with it - is it hooked up and good? ( i assume you have a 6bolt)

 

[steve]

Other than blowing a fuse somewhere I can't see how unplugging the connector for the fuel pump would cause you to stop having spark.

I'm afraid there isn't enough information here, or should I say too much missing information.
If you actually got the injectors swapped you may have unhooked the power transistor or coil.

Try to explain exactly what you did, when you did it, when you noticed that you no longer had spark and how you noticed. That might help uncover whats wrong.

 

[2g 6 bolt swap]

After the car wouldnt start after disconnecting the fuel pump we just kept working on putting my injectors in and taking off the intake mani to clean it. We figured we would figure out what was wrong putting it all back together but that didnt happen. The first thing i did to check for spark was i took a plug out and put it to the valve cover to see if it would spark. Got nothing on all four plugs. Checked power to the coil pack and even tried swaping a different coil pack in and still no spark. CAS is reading 4.5 volts of power at the green wire w/ the yellow stripe but when i took the CAS out to do a spin test on it, the injectors nor the spark plugs fired. With the key on isnt the powerwire to the CAS suppose to be 12 volts and when it cranks the CAS turns it down to 5 volts? MPI relay is good because it turns on when i turn the key, and the fuel pump relay is good because that clicks when the car is cranking. Another thing i dont get is when i crank the car over my rpms do not move at all. Also my afc isnt reading throttle or rpm. We took the ecu out and tested it on another 2g and it started right up, so isnt that ruled out also? I dont know what else to do. Thanks

 

[steve]

i have a 6 bolt.

Kind of guessed this one but important to include. 1G head and intake or 2G? What about the CAS, TB and TPS, PTM and coils, are they early 1G (90 style), 91+, or 2G parts?

The first thing I did to check for spark was I took a plug out and put it to the valve cover to see if it spark. Got nothing on all four plugs.

One plug at a time or all at once?

Check power to the coil pack and even tried swapping a different coil pack in and still no spark.

How/where did you check? Did you look at the two outputs from the PTM while cranking to see if they were pulsing?

CAS is reading 4.5 volts of power at the green wire w/ the yellow stripe but when i took the CAS out to do a spin test on it, the injectors nor the spark plugs fired.

Green/yellow? I don't think it connects to the CAS. Depending on how the swap was done the wires would be:

Red = +12v
Black = Ground
Blue/White = Crank Position
Blue/Red = Cam Position

Both of the position wires are pulled up to 5v by the ECU and the sensor(s) pull them to ground to signal the position. The ECU sees the change in voltage and clocks the edges when the voltage changes.

MPI relay is good because it turns on when I turn the key, and the fuel pump relay is good because that clicks when the car is cranking.

Just seeing the CEL turn on lets you know that the MPI is getting power, the ignition switch is putting out 12v in the IG1 terminal, the ECU is seeing it and activating the MPI relay.
On a 2G there isn't the extra input for activating the fuel pump during cranking so if you are really seeing the pump turn on the ECU has to be seeing some signals from the CAS.

Another thing I don't get is when I crank the car over my rpm do not move at all. My SAFC isn't reading throttle or rpm.

Everything is plugged back in from when we did the swap.

Also we took the ecu out and tested it on another 2g and it started right up.

The SAFC should be seeing both. Where did you wire up the RPM signal from for the SAFC.
The Apexi manual has you incorrectly use one of the transistor output from the ECU.
If you used the White wire on pin 58 that might explain why the Tach and SAFC don't see any RPM and point to looking more closely at the Power Transistor.

Does the connector on the Power Transistor still have the metal clip?

 

[2g 6 bolt swap]

Kind of guessed this one but important to include. 1G head and intake or 2G? What about the CAS, TB and TPS, PTM and coils, are they early 1G (90 style), 91+, or 2G parts? Has 1G head and intake. I believe all the other parts are from a 1G also. I bought a complete 1g motor from a 91.


One plug at a time or all at once?
Checked one plug at a time.


How/where did you check? Did you look at the two outputs from the PTM while cranking to see if they were pulsing? Checked for coil pulse and its not getting one with an ohmn meter and there is no pulse at the power transistor while cranking.



Green/yellow? I don't think it connects to the CAS. Depending on how the swap was done the wires would be:

Red = +12v
Black = Ground
Blue/White = Crank Position
Blue/Red = Cam Position

Both of the position wires are pulled up to 5v by the ECU and the sensor(s) pull them to ground to signal the position. The ECU sees the change in voltage and clocks the edges when the voltage changes.



Just seeing the CEL turn on lets you know that the MPI is getting power, the ignition switch is putting out 12v in the IG1 terminal, the ECU is seeing it and activating the MPI relay.
On a 2G there isn't the extra input for activating the fuel pump during cranking so if you are really seeing the pump turn on the ECU has to be seeing some signals from the CAS.




The SAFC should be seeing both. Where did you wire up the RPM signal from for the SAFC.
The Apexi manual has you incorrectly use one of the transistor output from the ECU.
If you used the White wire on pin 58 that might explain why the Tach and SAFC don't see any RPM and point to looking more closely at the Power Transistor. I hooked up a scan tool to see if there were any codes and i got a P0120 code saying the throttle position circuit has a malfuction.

Does the connector on the Power Transistor still have the metal clip?

Metal Clip? Confused here....

 

[steve]

Metal Clip? Confused here....

My mistake, the power transistor doesn't have a metal clip lock like the TPS.

http://www.dsmtuners.com/forums/151528353-post8.html

People report them coming loose and that would cause a proble, lile the one your having.

 

[2g 6 bolt swap]

All of my connections are fine. Even swapped a diff power transistor off a running dsm. I found two relays on top of my interior fuse box. Would those have anything to do with my ignition system and if not what are they?

 

[steve]

My thought processes are blocked until you answer the questions in post 5.

 

[2g 6 bolt swap]

All of my igniton components are for a 91 6 bolt motor. Also has a 1g head. When i checked for spark from the plugs i checked them one at a time but i dont see how that can make a difference because my injectors are not even firing. To check the pulse at the PTM do you just use an ohmn meter? Coil is not getting a pulse either. As far as my CAS wiring goes the green wire w/ the yellow stripe is my power wire. I guess its just the way it was wire at the shop i had it done at. Am i suppose to get a 12v reading at the power wire on the CAS with the key on? Finally i hooked up a scanner to my car today and it gave me a P0120 code which is the Throttle position circuit malfuction. Not sure if that has anything to do with it but i hope this info helps more.

 

[DDash]

If it is not your cas and it was working before you put the injectors, try checking your fuses, ecu, ignition,etc. Could be something simple.

 

[DDash]

About the tps sensor, i ran my car without one for weeks. It starts up everytime but acts funny on the throttle response.

 

[2g 6 bolt swap]

What would cause my afc to all of a sudden just stop reading. The car was in perfect running condition before all of this. It is no longer reading throttle or rpm when the car cranks. I thought it could possibly be my ecu, but me took it out and put it on another car and it started right up. If im not getting power a full 12v reading from my CAS with the key on what do i check from there? Is there a relay for that or does that have something to do with the ecu?

 

[rush2252]

okay ive been helping him out. All fuses double checked.. all connections are good. He has 12v+ to the three pin connector at the coils. His Fuel pump is priming. Hes getting zero injector pulse and zero pulse to the coils. The two relays he was referring to in the upper post are for heater and defrost. The ECU worked in another car.

 

[steve]

All of my igniton components are for a 91 6 bolt motor. Also has a 1g head.

When i checked for spark from the plugs i checked them one at a time but i dont see how that can make a difference because my injectors are not even firing.

To check the pulse at the PTM do you just use an ohm meter?
Coil is not getting a pulse either.

As far as my CAS wiring goes the green wire w/ the yellow stripe is my power wire. I guess its just the way it was wire at the shop i had it done at. Am i suppose to get a 12v reading at the power wire on the CAS with the key on?

Finally i hooked up a scanner to my car today and it gave me a P0120 code which is the Throttle position circuit malfunction.

I asked about the plugs because I'm not sure you will get a spark on either of the two plugs if both aren't grounded. The injector circuit is different than the ignition circuit. They share the CAS and ECU but have different power and logic.

There are 3 green/yellow wires going into the ECU but none for the CAS.
Pin 2 is for injector 3.
Pin 18 is for the ISC.
Pin 81 is the +5v sensor power. (It should be going to the TPS and MAF)

The 12v source for the CAS should be a red wire to pin 3 on the CAS.
Pin 4 should have a black wire and is ground. These two power the circuits in the CAS.
Pin 2 on the CAS is the Crank Position and should go to pin 89 (blue/white) on the ECU.
Pin 1 on the CAS is the Cam Angle and should run to pin 88 (blue/red) on the ECU.

With the CAS unplugged and the ignition both pin 1 and 2 should have 5v from the ECU on them. With the CAS plugged in they should either be at 5v or 0v depending on the position of the CAS and should toggle as you turn it.

There are test procedures for the PTM on the site but what your looking for is for the power transistor to pull the pin from the coil low to charge the coil and then let it go back to 12v and stop the current to fire the coil. You would use a the voltage scale for this too on a multimeter.

Typically I'd look first that the CAS and make sure the ECU is getting timing information, then look at the coils and make sure they are getting power along with the PTM driving them. If you don't see the PTM pulling it's side of the coil low then I'd check the signals going into the PTM from the ECU. Since your ECU runs in another car I would expect it to be outputting the correctly to the PTM if it's getting CAS information.

Double check the cause of your TPS CEL. I don't remember if the stock ECU cuts fuel and spark if it thinks your holding the throttle open during cranking.

 

[rush2252]

im gonne give a quick update. Weve been on the phone for a few hours and it looks like he is headed in the right direction. Somehow the TPS connector and the Connector to the CAS got mixed up. he switchede them and now He has injector pulse and fire to the plugs but I think the plugs are fouled they were wet when he pulled them out and it wont start. If not IDK what else man! im going to bed its late good luck

 

[steve]

I guess the green/yellow wire was the clue after all and all the connections weren't fine.

 

[rush2252]

he sent me a pic and I noticed the connectors looked similar on the CAS and TPS as I myself havnt worked on many 6bolts. He swapped them around and got fire but not enough to get it to start. He said it sounds different when cranking now also w the coil firing and injectors pulsing.

 

[2g 6 bolt swap]

Ok with connectors switched around the car turns over easy for a few revolutions then i abnormal sounds like the starter grinds. It gets spark now with the 4 prong clip that was hooked up to the TPS that is now hook up to the CAS. Something still doesnt sound right about how its turning over... Would this now how something to do with CAS timing since i removed it to spin check it when i thought it was bad. Also i took the CAS back out with the wires switch around and i hear the injectors pulse when i turn it and i hear the fuel pump at the same time. IS THAT RIGHT????

 

[rush2252]

ahh I forgot you pulled it out and switched it around.. I read somewhere that there is a notch that lines up but im not sure as Ive never messed with the 1g personally. Try getting on all data and see what it says. I know it can either go in correctly or 180 out and this can cause it to backfire and sound strange. Because the plugs arent firing in sync with the injector pulsing. I think your 80% there

 

[steve]

Would this now how something to do with CAS timing since i removed it to spin check it when i thought it was bad. Also i took the CAS back out with the wires switch around and i hear the injectors pulse when i turn it and i hear the fuel pump at the same time. IS THAT RIGHT????

Yes...

The CAS can only go into the cam two ways, correctly and 180 degrees off.

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Make sure that you are really grounding the pin for the timing adjust connector and not the plastic guard and that you have disconnected any datalogger (grounding pin 10 on the DLC at the same time will set the BISS adjustment mode not timing adjust mode)

Steve

Once it's correctly installed you still have to set it to sync the ECU and crankshaft to the same timing.