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The car was running fine before then one day went to garage to start car up and its running like crap. I come to find out that the number 2 and 3 cylinder are not sparking. I replaced both the coil pack and the ignitor, and still no spark. Was wondering if there may be a problem with the ecu or something else that I'm overlooking. Any help would be appreciated. Thanks
 

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I have a similar problem, but it's 1 and 4. I'm not getting a code reading through turning on and off the ignition, is there any way to tell the difference without just replacing parts?

I do have a Fluke 79 III and I know how to use it.
 

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First and foremost; I'm old school but not retarded... for the most part.

Ok, here's what I've done so far:

I crossed the signal (after remembering that Japanese technology breaks on the neutral) and I obtained spark on 1 & 4. I tested the ignition module per Haynes and it failed on 1 & 4, so I replaced the module... no it didn't cure the problem. I tried to trace and dug through the car and managed to dig what I believe is the ECU from under the center section of the dash. There, I grounded the signal coming from the coil and looked for it at the ECU. I didn't find it, nor the working signal.

So, is there something that breaks connection when the car is off?

I found the same color code at the ECU, but the gage was different, or am I looking at the wrong thing?

The more I look at this thing, the more I miss my '72 Stang.

Sorry if I offended.
 

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Cat Skinner said:
So, is there something that breaks connection when the car is off?
Nope, is this for the '95?

The VFAQ site has both the 1G and 2G pinouts but I have some doubts about how valid the 2G one is. I think there were some errors in one of the FSM that got copied into the VFAQ.

Steve
 

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first did you check the plugs and wires? after my re-build i couldnt get 2&3 to fire and i was clueless. came to find out i forgot the brake booster vac line and it was causing those 2 cyls to have a lean misfire
 

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stevep said:
Nope, is this for the '95?

The VFAQ site has both the 1G and 2G pinouts but I have some doubts about how valid the 2G one is. I think there were some errors in one of the FSM that got copied into the VFAQ.

Steve
Ummm... vfaq.com? Just found the place thanks to you. Stoopid question: what's the difference between a 1G and a 2G? And yes, this is '95 Eagle Talon.

Oh, and if vfaq explains the difference, I apologize... I haven't had time to explore yet.
 

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91awdtsi said:
The car was running fine before then one day went to garage to start car up and its running like crap. I come to find out that the number 2 and 3 cylinder are not sparking. I replaced both the coil pack and the ignitor, and still no spark. Was wondering if there may be a problem with the ecu or something else that I'm overlooking. Any help would be appreciated. Thanks
Sorry if I hijacked your thread, but I figured the symptoms were similar. If you want, I can move.
 

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dsm239 said:
first did you check the plugs and wires? after my re-build i couldnt get 2&3 to fire and i was clueless. came to find out i forgot the brake booster vac line and it was causing those 2 cyls to have a lean misfire

I'm not sure about 91awdtsi's case, but I took a timing light to verify spark as well as pulling each plug individually. And with the plume of gasoline vapors when I cranked her over, I'm pretty sure she's getting plenty of go juice.

Plugs and wires are brand new, had no idea what life was left on the old, just bought the car last summer.
 

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stevep said:
Nope, is this for the '95?

The VFAQ site has both the 1G and 2G pinouts but I have some doubts about how valid the 2G one is. I think there were some errors in one of the FSM that got copied into the VFAQ.

Steve
Now I really feel stoopid.
1G, 1rst generation...

duh.
 

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stevep said:
I have some doubts about how valid the 2G one is.
I checked the manual against the VFAQ for the ignition. ECU Pin 10 (Brown/Red) is the output of the ECU for the power transistor A to fire the coil for 1 & 4. Pin 23 (Black/Blue) is for power transistor B to fire the coil for 2 & 3.

The output of power transistor A (White) runs to the RPM check connector under the hood, turns into a red wire and goes to its coil. The output of power transistor B (Black) only goes to its coil.

So I retract my earlier comment, The power transistors (Ignition Module) are between the coil and the ECU. You talked about swapping the ignition module and then talked about grounding the output at the coil.

Sorry I misunderstood before.

Steve
 

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stevep said:
The output of power transistor A (White) runs to the RPM check connector under the hood, turns into a red wire and goes to its coil. The output of power transistor B (Black) only goes to its coil.
Sorry to interrupt the turkey and games, but you lost me on this one... the RPM check connectoer, is that another name for the crank shaft position sensor?

BTW, great information. You've given me something to chase.
 

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There is a connector under the hood used when setting the Base Idle Speed so you can hook up a tach while you adjust the BISS. It's connected, like I said, to the output of power transistor A and pulses everytime the coil for 1 & 4 is charged and fired.

The coils are fed battery voltage on one side of the primary and the other side of the primary is connected to one of the power transistors in the power transistor module (PTM). The ECU causes the power transistor to pull that side to ground so current flows through the coil and when the ECU switches it off the plugs fire. I haven't spent the time to look at what the signal from the ECU to the power transistors looks like.

The ECU figures out which power transistor to switch and when from the crank and cam angle sensors.

So, the first thing to check is the output of the ECU to the transistors, If both are pulsing when you crank the engine then check at the PTM inputs for the same signal and at the outputs of the PTM for battery voltage being pulled to ground.

Steve
 

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stevep said:
There is a connector under the hood used when setting the Base Idle Speed so you can hook up a tach while you adjust the BISS. It's connected, like I said, to the output of power transistor A and pulses everytime the coil for 1 & 4 is charged and fired.

Steve
Dude, you are a blessing... lemme guess, you've owned a couple of these before...
 

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OK, bear with me, this isn't going to be short. First, no I didn't get the problem corrected, just had to drop it for a while.
I had the ECU tested, works fine. Replaced the ignition module (failed according to Haynes), still nothing on cylinders 1 & 4. Tested cam angle sensor, things went weird. First, Haynes has the pins as 1: Power 2: Ground 3: Signal. When I took readings, I got the following: 1: 12 VDC 2: 5 VDC 3: 0 VDC, but terminal 3 had 40 ohms to ground when ignition was on and 0 ohms to ground when off (I assume that's my ground). The result of these readings were with the ignition on and the engine off. I disconnected the plug wires and took the readings again while turning over the engine, 1: still 12, 2: a steady 5 and 3 still 0. Assuming 2 is the signal (BTW, 1 is red, 2 is blue and 3 is black), Haynes claims that it should fluctuate between .4 and 3 volts. It also states that if you have supply voltage but no signal (I had 5 volts) that you need to replace the sensor.

Can anybody interpret this??

This also leads me to a few questions:

- Am I correct in assuming what my wires are 1 power 2 signal 3 ground?

- Why does my ground go to 40 ohm when the ignition is energized but 0 when turned off?

- Steve mentioned the RPM check connector under the hood, I'll be dipped if I can find it, any clues where it would be or what it might look like?

- If the sensor is bad... why the hell does 2 & 3 fire??

If someone can help, please do. The next step is to tow it to a garage and that would do insurmountable damage to my ego.
 

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On a side note, my cam angle sensor is located next to the intake timing gear, not on the back side of the block as stated in haynes, if that makes any difference.

I've been thinking about using that manual for toilet paper....
 
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