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No spark on cylinder 1 and 4

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There are primary and secondary readings, I dont know which one you tested. Where are you taking the readings from?
 
Also after you test the MFI relay and nothing good. By pass it. And see if the car turns over. Oh also when testing make sure you ground it with a jumper wire.
 
This is a link to the electric diagram of a 2G courtesy of DSMLink.

http://www.dsmlink.com/images/forums/2GECUMFI.pdf

If you look at it (pag.3) you can see that if only 2 cylinders (1 & 4) do not fire it has to be one of the following:

1 - bad 1&4 coil
2 - bad wiring between power transistor and coil 1&4 (check also a-59 speed detection connector)
3 - bad power transistor
4 - bad wiring between ECM and power transistor (if ground was the problem 2&4 wouldn't fire either)
5 - bad ECM (power transistor drives)

That should narrow it down and allow you to exclude each point before moving to another. Keep in mind that sometime more than one part goes bad at the same time or one failure can be the consequence of another so once you replace a part with a known good part do not put the original back on just because the problem has not been solved.

For your reference (from the FSM):

Primary coil (power transistor side) resistance range is 0.70 to 0.86 Ohm
Secondary coil (Spark plugs size) resistance range is 11.3 to 15.3 KOhm

Also do not overlook:

Spark plug gap 0.7 to 0.8 mm (.028 to .031 in.)
Spak plug cable max resistance 22 KOhm
 
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1. Starter issue: Without looking at your profile I'm assuming you have a 5 speed. The clicking you hear is a relay located under your radio. Not going into detail about how it works but your problem is your clutch switch. There are two switches on the clutch pedal assembly, unplug the upper one. You probably won't be able to see the switch the connector is located on the front of the pedal assembly above the lower switch, I believe it is white. Boom now your car starts with the key, but you no longer need to have the clutch pushed in to start so keep that in mind.

2. No spark on 1 & 4: If you've tried all the above mentioned possibilities, you'll need to check for continuity between the power transistor plug (black/white pin 8) and the ignition coil plug (blue/red). If you don't have connection between those two your engine speed connector is bad (upper firewall), chop that bad dog off and solder those wires together.

If you do have continuity between those wires read the following posts and test for 12v at the power transistor connector.


http://www.dsmtuners.com/forums/newbie-forum/340317-ptu.html#post151903320
http://www.dsmtuners.com/forums/newbie-forum/358422-power-transistor-pinout-help.html

Hope this helps.
 
Coil 1 and 4 14.06, Coil 2 and 3 13.16.
These are secondary readings at the output side of the coil (Coil one is a little on the high side-almost a sign that this side is toast since it's out of range. Be nice to see 10.3 to 13.9 KOhms if possible).

The question is: did you do Ohm readings on the primary side which should between .77 to .95 Ohms per each oil. If these two numbers are out of range, the 1-4 primary coil is bad causing the secondary coil not to function very well, or not at all and coil needs replacing.

On the connector itself, you put black lead on pin 3 and touch 1 for one side to get that reading, then touch pin 2 for the other reading. Compare readings and see what you get.

Forget about that DSMLink nonsense - we need the hands on meter reading basics here.

Good luck - DSM
 
1. Starter issue: Without looking at your profile I'm assuming you have a 5 speed. The clicking you hear is a relay located under your radio. Not going into detail about how it works but your problem is your clutch switch. There are two switches on the clutch pedal assembly, unplug the upper one. You probably won't be able to see the switch the connector is located on the front of the pedal assembly above the lower switch, I believe it is white. Boom now your car starts with the key, but you no longer need to have the clutch pushed in to start so keep that in mind.

2. No spark on 1 & 4: If you've tried all the above mentioned possibilities, you'll need to check for continuity between the power transistor plug (black/white pin 8) and the ignition coil plug (blue/red). If you don't have connection between those two your engine speed connector is bad (upper firewall), chop that bad dog off and solder those wires together.

If you do have continuity between those wires read the following posts and test for 12v at the power transistor connector.


http://www.dsmtuners.com/forums/newbie-forum/340317-ptu.html#post151903320
http://www.dsmtuners.com/forums/newbie-forum/358422-power-transistor-pinout-help.html

Hope this helps.

I will check this when I get home today and post my findings. Thanks for the help I hope I get this problem solved soon.

Did you do any work to your car before it stopped working?

The car has been sitting for a couple of years while I was building the motor and now I am trying to get the car running but I encountered a couple of problems.

These are secondary readings at the output side of the coil (Coil one is a little on the high side-almost a sign that this side is toast since it's out of range. Be nice to see 10.3 to 13.9 KOhms if possible).

The question is: did you do Ohm readings on the primary side which should between .77 to .95 Ohms per each oil. If these two numbers are out of range, the 1-4 primary coil is bad causing the secondary coil not to function very well, or not at all and coil needs replacing.

On the connector itself, you put black lead on pin 3 and touch 1 for one side to get that reading, then touch pin 2 for the other reading. Compare readings and see what you get.

Forget about that DSMLink nonsense - we need the hands on meter reading basics here.

Good luck - DSM

Ill test the primary side of the coil later today and post the numbers.
 
Forget about that DSMLink nonsense - we need the hands on meter reading basics here.


I am not sure if your comment is aimed at the link I posted but as I mentioned it shows the factory electrical drawings for the ignition of the OP's car, it just happens to be available on the DSMLink website.

I corrected the measuring unit for the secondary, I must have misread the manual.
 
While out of nominal tolerance, if you take into account the accuracy of the ohmmeter and the fact that such a low resistance is possibly comparable to the one of the meter cables themselves I wouldn't worry about the coils. Keep in mind they are just that, a coil of electrical wire, if broken you would have a much higher value.
 
EDIT:(Sorry on jumping the gun on the "DSMLink" comment-my bad...)

Check plugs as well. Seen plugs go bad for some odd reason or another when you think it's sparking okey, but get it in a pressurized condition and they refuse to work.
 
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Did you check the wiring ?

(checked) 1 - bad 1&4 coil
(checked) 2 - bad wiring between power transistor and coil 1&4 (check also a-59 speed detection connector)
(checked) 3 - bad power transistor
(checked) 4 - bad wiring between ECM and power transistor (if ground was the problem 2&4 wouldn't fire either)
(checked) 5 - bad ECM (power transistor drives)

The only one I have not checked has been the wiring between the power tranistor and the coil pack but, I believe I actually did check this a couple of weeks ago but I will recheck today just to make sure.
 
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This is just a guess below, but can't help think since there is a common trail to follow:

I'm seeing here above is a very dry harness that has plenty of dried up insulation over the wires causing some corrosion to "creep in the cracks" so to say and causing some resistance issues in making a complete circuit.

It's like a bad battery cable connection going to the connector where the corrosion needs to be cut out and connector reattached to the bright copper wire to make good again.

That harness is under the hood with all of the heat surrounding it and baking it all in abundant heat.

Plus, all of our cars are well over 10 plus years which age is the punishing factor in anything vulnerable to this on main attribute.

..only a thought but one can't help but wonder.

-DSM
 
Ok guys I have an update. I installed a new crank sensor and now I have spark on cylinders 1 and 4 so im guessing that was one of my problems but now I have no spark on cylinders 2 and 3. Also a check engine light came on and the code was for a cam sensor so I check the wires first to make sure it was getting the proper volts and the wires were fine so I went and bought a new cam sensor thinking it was going to fix my problem and it didnt. So now I have spark on 1 and 4 but not 2 and 3 any ideas?

I think your crank sensor was installed 180 degrees incorrectly or just incorrectly. Or maybe a bad unit? I installed one when I was getting no spark on 2 cylinders and it fixed it :).I think you already tested the rest of your ignition system, Only thing I can think of that you haven't tested is the ecu, But my 90 ecu is still hardly damaged so I wouldn't think that is your problem, but if nothing else check that for damage and if anything looks messed up send a picture to ecmlink staff or just send it in for service they're the best(IMO) and do quick work.

If you think you might have installed it wrong do a search and there's a lot of info on it.
 
Ok guys I have an update. I installed a new crank sensor and I still do not have spark on 2 cylinders. Also a check engine light came on and the code was for a cam sensor so I check the wires first to make sure it was getting the proper volts and the wires were fine so I went and bought a new cam sensor thinking it was going to fix my problem and it didn't. I am not getting signal on one coil does anyone have a engine harness diagram?
 
Hello everyone I just wanted to keep you guys updated. I finally got the other 2 cylinders to fire. The problem was on the side of the CAS there is a small rotor that goes connected to the intake camshaft. There is a screw that connects the rotor to the camshaft and it was loose so the rotor wasn't spinning when I would crank the motor. Once I fixed that problem it started right up.
 
Im having this exact problem its great to find this thread, only question i have, is i have a 96 and thinking about changing the CAS to a 97 i know i need the 97 cam but is there anything else ill have to do?
 
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