ICM keeps dieing?
11-07-2011, 02:32 PM
#1
ICM keeps dieing? im currently having an issue with my car. it keeps stalling and does want to crank up until its extremely cold and sometimes it just doesnt start.
ive bought around 3 ICM's.
Every one of them keeps getting error code16 low res. and last night i finally got error code 42 = ICM grounded? i think i have a sort of shortage somewere.
When im driving and i feel like its about to stall. i see the RPM's go down.
if keep my feet on the gas pedal. rpms start to go back to normal and car dies. after that car doesnt start until its cools down.
I got new Opti, New Sparkplugs and wireset and New Coil. New racetronix fuel pump.
No coolant leaks at all. trust me i double checked.
Has anyone else experienced this? If so, please help a brother out.
am i missing something?
ive bought around 3 ICM's.
Every one of them keeps getting error code16 low res. and last night i finally got error code 42 = ICM grounded? i think i have a sort of shortage somewere.
When im driving and i feel like its about to stall. i see the RPM's go down.
if keep my feet on the gas pedal. rpms start to go back to normal and car dies. after that car doesnt start until its cools down.
I got new Opti, New Sparkplugs and wireset and New Coil. New racetronix fuel pump.
No coolant leaks at all. trust me i double checked.
Has anyone else experienced this? If so, please help a brother out.
am i missing something?
11-07-2011, 02:49 PM
#2
There's a chance the pigtail that connects the opti to the main harness is at fault. Have a look at the ends at the opti and the connector to the main harness at the pass. side of the intake next to the purge solenoid. Might have crud or corrosion on the contacts...
11-08-2011, 08:53 PM
#5
i checked the ICM connector and the opti wiring harness. they both look good.
i did the opti harness voltage test with the key on without cracking car. as stated in shbox.com
A - 5vdc
B - 5vdc
C - 12vdc or system voltage
D - 0-0.2 ohms ground.
results i tested are as follows
A - 7.6vdc
B - 7.6vdc
C - 18.6vdc or system voltage
D - 0-0.3 ohms ground.
those are my testing results.
can there be something wrong with that?
im not really good with electric stuff. lol.
can having to much volts effect?
i have done all visual test on all connectors and they all seem good. i moved wires while car on and car didnt die.
i reved it like 3-6 times from 2-3,000 rpms and it died on me. turned car off and car wont start backup. w0wzerz.
i need fix asap. anyone close near garland, TX that can help me out. il buy u lunch and beer
i did the opti harness voltage test with the key on without cracking car. as stated in shbox.com
A - 5vdc
B - 5vdc
C - 12vdc or system voltage
D - 0-0.2 ohms ground.
results i tested are as follows
A - 7.6vdc
B - 7.6vdc
C - 18.6vdc or system voltage
D - 0-0.3 ohms ground.
those are my testing results.
can there be something wrong with that?
im not really good with electric stuff. lol.
can having to much volts effect?
i have done all visual test on all connectors and they all seem good. i moved wires while car on and car didnt die.
i reved it like 3-6 times from 2-3,000 rpms and it died on me. turned car off and car wont start backup. w0wzerz.
i need fix asap. anyone close near garland, TX that can help me out. il buy u lunch and beer
11-08-2011, 09:52 PM
#6
TECH Veteran
I don't know how you can get more than 5v when the PCM does not put out more than 5v. If your system voltage is really 18.6v, that could cause some damage to your car from over voltage. I'd be finding out why the voltage is so ridiculously high (right now, I'd suspect your readings are in error).
11-08-2011, 10:45 PM
#7
il double check, but just to make sure what im doing.
I am i suppose to check the A-D from the the optispark harness correct?
from the connector that goes to the optispark right.
if so, thats what im getting i tested it 3 timse to make sure.
thats why im like w0w that cant be right. maybe thats why im having ignition issues.
what do you recommend i do? il also try and test it and put a video link. just to make sure and let me know if i did it wrong.
I am i suppose to check the A-D from the the optispark harness correct?
from the connector that goes to the optispark right.
if so, thats what im getting i tested it 3 timse to make sure.
thats why im like w0w that cant be right. maybe thats why im having ignition issues.
what do you recommend i do? il also try and test it and put a video link. just to make sure and let me know if i did it wrong.
Trending Topics
11-08-2011, 10:55 PM
#8
I have been following this from thes idelines and I guess it is time to comment on it. First I have to agree with Rob (usually do). Your readings are way too high and honestly I don't know how they could even be that high...... that and the fact that you are supposed to test AC volts on one of those pins, and it should be 0-5 volts AC toggling back and forth while cranking. That ensures that the PCM is doing its thing, and what actually tells the coil to spark.
I suggest testing each of those pins again. Test them to an engine ground, and then to the harness ground that is in the connector. Make sure to switch the meter to AC and test the last pin ( I dont want to say which cuz I could be mistaken given my bad memory) and have someone crank it.
Get back to us when you have done this. I am confident we can walk you through this and get it figured out.
I suggest testing each of those pins again. Test them to an engine ground, and then to the harness ground that is in the connector. Make sure to switch the meter to AC and test the last pin ( I dont want to say which cuz I could be mistaken given my bad memory) and have someone crank it.
Get back to us when you have done this. I am confident we can walk you through this and get it figured out.
11-09-2011, 01:08 AM
#9
I don't know how you can get more than 5v when the PCM does not put out more than 5v. If your system voltage is really 18.6v, that could cause some damage to your car from over voltage. I'd be finding out why the voltage is so ridiculously high (right now, I'd suspect your readings are in error).
Al
11-09-2011, 06:36 AM
#10
TECH Veteran
I have been following this from thes idelines and I guess it is time to comment on it. First I have to agree with Rob (usually do). Your readings are way too high and honestly I don't know how they could even be that high...... that and the fact that you are supposed to test AC volts on one of those pins, and it should be 0-5 volts AC toggling back and forth while cranking. That ensures that the PCM is doing its thing, and what actually tells the coil to spark.
I suggest testing each of those pins again. Test them to an engine ground, and then to the harness ground that is in the connector. Make sure to switch the meter to AC and test the last pin ( I dont want to say which cuz I could be mistaken given my bad memory) and have someone crank it.
Get back to us when you have done this. I am confident we can walk you through this and get it figured out.
I suggest testing each of those pins again. Test them to an engine ground, and then to the harness ground that is in the connector. Make sure to switch the meter to AC and test the last pin ( I dont want to say which cuz I could be mistaken given my bad memory) and have someone crank it.
Get back to us when you have done this. I am confident we can walk you through this and get it figured out.
Last edited by shbox; 11-09-2011 at 07:44 AM.
11-09-2011, 08:37 AM
#11
11-09-2011, 09:10 AM
#12
What i do remember is that i got perfect results.
I did the following. from shbox.com
Disconnect the ICM connector. Leave coil connected.
Turn key to ON.
Check for dc voltage with a digital meter at harness terminal "A" to ground and and also "D" to ground. Note: Use a modern digital meter with at least 10 megohm impedance to protect the PCM (in case you measure anything in that direction).
Result should be 10v dc or more on both terminals. If you get no voltage, use the diagram and chase back toward the coil and the ignition fuse. Power for the ICM comes from the ignition fuse and through the coil, so any of that could be bad.
If you have good voltage, switch the meter to ac scale and connect test leads to terminal "B" and to ground. Observe meter while cranking the engine. You should see between 1 and 4 volts ac (those are the pulses that trigger the coil to fire).
I got 10v dc on both terminals A and D.
so im getting good voltage from the fuse and the coil.
On Terminal B to ground while cranking. I received about 2-4 volts ac.
then i tested the opti harness which i got the above results.
when car is on idle. i move icm wires, coil wires and ecm wiring harness. car doesnt shutoff which is good sign. il have my scanner plugged in. soon as i start revving car on warm of course. on the 3rd rev or more car just dies and then il get error code 16, after car dies. it start backup.
if the optio harness results are correct, this will be very scary.
all that testing is done when car is off and warm.
i will test with car cold.
that way i can verify if its a warming up issue.
back to the top. i will post a video after work and let me know what im doing wrong or what not. i appriciate you guys helping me out.
Last edited by davidc212k; 11-09-2011 at 09:18 AM.
11-09-2011, 10:17 AM
#13
ok. i watched the following video and it helped alot.
http://www.youtube.com/watch?nomobile=1&v=lFCjaz6zHfc
i remember when i bought the intake elbow. i never plugged in the inlet ventalation hose.
video stated it can cause misfires. i guess i will have to fix that 1st.
http://www.youtube.com/watch?nomobile=1&v=lFCjaz6zHfc
i remember when i bought the intake elbow. i never plugged in the inlet ventalation hose.
video stated it can cause misfires. i guess i will have to fix that 1st.
11-09-2011, 07:33 PM
#14
i did the testing once again. key was on without cranking. to test the voltage coming from the opti harness. about the inlet hose that goes from the opti vented line to the cold air intake elbow thing, il have that done by the weekend.
enjoy the video and my poor communication, lol.
http://www.youtube.com/watch?v=ooztX...ature=youtu.be
tested by having the red cable from the multimeter to the optispark harness terminals and the black cable to ground from the car.
i also disconnected the optispark harness from both connections.
so i got the following from the cars main wiring harness terminals A to D.
A - 6.79
B - 6.83
C - 16.09
D - 0.02
so that lets you know its not the optispark harness. in other words the incorrect voltage is coming from the LT1 complete wiring harness. i need to disconnect the coil connection and the CIM connection and do the test again. if i get lower voltages that means there a shortage in the ICM or coil wires. i could be wrong about that. since voltage comes 1st from the fuse to the PCM then to opti module - icm then to coil.
i hope i got that part correct. lol.
enjoy the video and my poor communication, lol.
http://www.youtube.com/watch?v=ooztX...ature=youtu.be
tested by having the red cable from the multimeter to the optispark harness terminals and the black cable to ground from the car.
i also disconnected the optispark harness from both connections.
so i got the following from the cars main wiring harness terminals A to D.
A - 6.79
B - 6.83
C - 16.09
D - 0.02
so that lets you know its not the optispark harness. in other words the incorrect voltage is coming from the LT1 complete wiring harness. i need to disconnect the coil connection and the CIM connection and do the test again. if i get lower voltages that means there a shortage in the ICM or coil wires. i could be wrong about that. since voltage comes 1st from the fuse to the PCM then to opti module - icm then to coil.
i hope i got that part correct. lol.
11-09-2011, 07:59 PM
#15
now i disconnected the coil wires and the ICM wire including the optispark harness.
connected the multimeter to the main wiring harness that goes to the opti harness.
The one in the black color.
got the same results.
A - 6.79
B - 6..79
C - 16.03
D - 0.03
so that rules out the opti, the coil and the ICM.
if im correct the issue is the cars wiring harness or the PCM. damn it. please tell im doing this wrong.
connected the multimeter to the main wiring harness that goes to the opti harness.
The one in the black color.
got the same results.
A - 6.79
B - 6..79
C - 16.03
D - 0.03
so that rules out the opti, the coil and the ICM.
if im correct the issue is the cars wiring harness or the PCM. damn it. please tell im doing this wrong.
11-11-2011, 12:51 PM
#18
I'm going to attempt to help you. Hook your meter directly across the battery and tell me the voltage it reads. Engine off, key off.
The ICM has four wires going to it. Put the red lead from your meter on the positive battery terminal and the black lead on ICM terminal A. You can unclip the back of the connector, pull out the rubber seal and get a small wire in the connector with it still plugged into the ICM. Do not unplug the connector from the ICM. With the key on engine off what's the voltage reading?
With the black wire of the meter on the negative battery terminal and the red lead on terminal C of the ICM what's the voltage? Again, key on engine off.
You can't really get any good information on terminal B or D of the ICM with your meter so don't waste time with it.
Are you running the stock coil?
Post the information and I'll get back to you.
Al 95 Z28
The ICM has four wires going to it. Put the red lead from your meter on the positive battery terminal and the black lead on ICM terminal A. You can unclip the back of the connector, pull out the rubber seal and get a small wire in the connector with it still plugged into the ICM. Do not unplug the connector from the ICM. With the key on engine off what's the voltage reading?
With the black wire of the meter on the negative battery terminal and the red lead on terminal C of the ICM what's the voltage? Again, key on engine off.
You can't really get any good information on terminal B or D of the ICM with your meter so don't waste time with it.
Are you running the stock coil?
Post the information and I'll get back to you.
Al 95 Z28
11-11-2011, 01:56 PM
#19
I'm going to attempt to help you. Hook your meter directly across the battery and tell me the voltage it reads. Engine off, key off.
The ICM has four wires going to it. Put the red lead from your meter on the positive battery terminal and the black lead on ICM terminal A. You can unclip the back of the connector, pull out the rubber seal and get a small wire in the connector with it still plugged into the ICM. Do not unplug the connector from the ICM. With the key on engine off what's the voltage reading?
With the black wire of the meter on the negative battery terminal and the red lead on terminal C of the ICM what's the voltage? Again, key on engine off.
You can't really get any good information on terminal B or D of the ICM with your meter so don't waste time with it.
Are you running the stock coil?
Post the information and I'll get back to you.
Al 95 Z28
The ICM has four wires going to it. Put the red lead from your meter on the positive battery terminal and the black lead on ICM terminal A. You can unclip the back of the connector, pull out the rubber seal and get a small wire in the connector with it still plugged into the ICM. Do not unplug the connector from the ICM. With the key on engine off what's the voltage reading?
With the black wire of the meter on the negative battery terminal and the red lead on terminal C of the ICM what's the voltage? Again, key on engine off.
You can't really get any good information on terminal B or D of the ICM with your meter so don't waste time with it.
Are you running the stock coil?
Post the information and I'll get back to you.
Al 95 Z28
11-11-2011, 11:47 PM
#20
Going to the drags tomorrow so I'm off to bed. If I have some time I'll check here tomorrow morning and see if you did the tests.
Al 95 Z28, TH400, S60 all loaded up and ready to go.
Al 95 Z28, TH400, S60 all loaded up and ready to go.