93 wont start
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From: nc
still not starting and running ok checked the order on the wire there all correct the car trying to back fire like that seems like it is out of timing to me any advice on this. I replaced the opti but there is only one way it will go correct and also the plugs are less than a month old if this helps .
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From: Maricopa, AZ
ok checked the order on the wire there all correct the car trying to back fire like that seems like it is out of timing to me any advice on this. I replaced the opti but there is only one way it will go correct and also the plugs are less than a month old if this helps .
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Joined: Dec 2010
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From: Maricopa, AZ
That could be a problem. I think at this point you need to put an Oscilloscope on it and see if the pulses are sent out at the right time.
Did you take apart the old Opti and look inside of it? If it has the Mitsubishi sensor it may be worth putting it back on with the cap and rotor off the new unit. A little trick to this is to use a screw from the TB cover plate as a "socket" to the Optispark screws to get it apart.
Also, have you had the ICM tested yet? If not, have it tested at least 4 times in a row. It needs to get hot, these are prone to heat failure but work again when cold.
Did you take apart the old Opti and look inside of it? If it has the Mitsubishi sensor it may be worth putting it back on with the cap and rotor off the new unit. A little trick to this is to use a screw from the TB cover plate as a "socket" to the Optispark screws to get it apart.
Also, have you had the ICM tested yet? If not, have it tested at least 4 times in a row. It needs to get hot, these are prone to heat failure but work again when cold.
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From: nc
That could be a problem. I think at this point you need to put an Oscilloscope on it and see if the pulses are sent out at the right time.
Did you take apart the old Opti and look inside of it? If it has the Mitsubishi sensor it may be worth putting it back on with the cap and rotor off the new unit. A little trick to this is to use a screw from the TB cover plate as a "socket" to the Optispark screws to get it apart.
Also, have you had the ICM tested yet? If not, have it tested at least 4 times in a row. It needs to get hot, these are prone to heat failure but work again when cold.
Did you take apart the old Opti and look inside of it? If it has the Mitsubishi sensor it may be worth putting it back on with the cap and rotor off the new unit. A little trick to this is to use a screw from the TB cover plate as a "socket" to the Optispark screws to get it apart.
Also, have you had the ICM tested yet? If not, have it tested at least 4 times in a row. It needs to get hot, these are prone to heat failure but work again when cold.
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From: Maricopa, AZ
Oscilloscope- There are PC based Oscilloscopes available online. I've never had to use one. What you are looking for is that the low res signals line up with the pistons. You could also make your own timing marks on the crank pulley and block and use a timing light and see where that is in reference to commanded spark advance at start up in the tune.
ICM- Yes they can, I don't know if they will though.
ICM- Yes they can, I don't know if they will though.
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its alive but ok its running again and when I first got it running it would not idle and after going around the block a few it was idling low but it would stay running idling about 700 then went out to some back road got down on it a few times come home had a water leak fixed that just a hose loose then it started running funny like skipping but if I held the gas to keep it around a grand its fine let off and the voltage drops down to around 8 .so I checked the codes I have a 15 ,36 ,53 I know I probally need to change the coolant sensor ill do that tomorrow what about the 36 code
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I think you need to fix 53 before you replace the coolant sensor.
From what I see code...
15 is coolant temperature sensor (signal voltage high)
36 is Opti-Spark Ignition system (high resolution pulse)
53 is System Overvoltage
From what I see code...
15 is coolant temperature sensor (signal voltage high)
36 is Opti-Spark Ignition system (high resolution pulse)
53 is System Overvoltage
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still running Ok today I took the battery and alternator off and took it to the local parts store and the alternator checked good on three different test . Then I had to leave the battery and they charged it all day and it tested bad it would only show 4volts and only 89 ca amps . So new battery and the amps are back up on the gauge around 13 or so and idling better. Im also only showing the number 12 code now witch means its checking codes correct? Ok new problem last night car ran hot took rad cap off while running and it was throwing out water like it was throwing up lol it would come up big time then disappear and the again. today after I got the new battery in and alt I run the car again a few min and could not see any water flowing in the flues in the rad. and I checked the water pump shaft and it was turning so were should I start . I think if I can get this fixed and I going to replace the alt. anyways because I don't trust the test they put it threw today .
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lt1 still not starting Ok working on Camaro again was running pretty good had a lil skip and now will not start back up. I have replace the opti spark new msd coil and control model or icm .Please help with this I would love to drive the car again this summer since I have spent this money in it trying to get it back right and thanks for your help guys .
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From: Maricopa, AZ
93 wont start Ok working on Camaro again was running pretty good had a lil skip and now will not start back up. I have replace the opti spark new msd coil and control model or icm .Please help with this I would love to drive the car again this summer since I have spent this money in it trying to get it back right and thanks for your help guys .
If the coolant temp sensor for the PCM, the one on the waterpump, is reading high voltage, that means its failed, and it fails to -40 degrees. The PCM thinks its -40 degrees and pours fuel in to try to warm it up, but if its actually warm it causes very hard start and runs rough. Replace that first, its $12, or google the Ohms resistence it should be and measure it to see if its ok, then look at the wiring. my yukon had it fail and caused your problems. Not the one in the block on the driver side, that's for the gage, the one in the waterpump.
Are you still on the NAPA optispark that was "skipping" (Misfiring)? I've dealt with a few parts store optisparks....they all sucked and either didn't work at all or had sporadic misfires before they self destruct and won't start the car anymore. GM or MSD optispark is the only way to go.
If the coolant temp sensor for the PCM, the one on the waterpump, is reading high voltage, that means its failed, and it fails to -40 degrees. The PCM thinks its -40 degrees and pours fuel in to try to warm it up, but if its actually warm it causes very hard start and runs rough. Replace that first, its $12, or google the Ohms resistence it should be and measure it to see if its ok, then look at the wiring. my yukon had it fail and caused your problems. Not the one in the block on the driver side, that's for the gage, the one in the waterpump.
You can scan the car first to confirm that before throwing parts at it; the PCM knows the coolant temp. When mine had this issue the PCM was reading -40 coolant temp like you mention. The car would still start just fine however....just ran very rich and got very bad gas mileage.
I'm not sure if you fixed it but make sure you have spark start at plugs and work back and just a word of caution you may have spark all the way to plugs but not proper spark either weak or sparking at the wrong time. I had chased a no start for 2 months I had spark and fuel. But found out that my icm was pulsating but not at the right time to start so I throw a used one on from a blazer and it fired right up you could always just go to the junk yard grab a few off of any blazer or f body and try them and try to avoid none factory parts they don't have a tendency to always last long
42 - Ignition control circuit, short or grounded- check the ICM and it's grounds, wires, and connectors.
STOP REPLACING THE OPTI'S!!!!! Holy ***** people! If the injectors AND spark fails it's most likely an Opti failure. If EITHER work it's not the Opti!
So sick of this automatic blame the Opti's crap. Look at how many people replace the Opti's and it NOT fix the problem. It's nuts!
OP, put a spark tester on it (one that induces a load) and check for a GOOD spark. If your injectors are getting a signal the optical sensor is good. But the distributor (cap and rotor) could be bad.
Also, recently my machinist told me that the cheap Opti's have been pressed together wrong causing the timing disc to be more than a few degrees off from where they should be. This recently caused havoc on one of his customers cars (3 cheap Cardone Opti's in a row!). They bought a Delphi and problems were solved.
STOP REPLACING THE OPTI'S!!!!! Holy ***** people! If the injectors AND spark fails it's most likely an Opti failure. If EITHER work it's not the Opti!
So sick of this automatic blame the Opti's crap. Look at how many people replace the Opti's and it NOT fix the problem. It's nuts!
OP, put a spark tester on it (one that induces a load) and check for a GOOD spark. If your injectors are getting a signal the optical sensor is good. But the distributor (cap and rotor) could be bad.
Also, recently my machinist told me that the cheap Opti's have been pressed together wrong causing the timing disc to be more than a few degrees off from where they should be. This recently caused havoc on one of his customers cars (3 cheap Cardone Opti's in a row!). They bought a Delphi and problems were solved.
