LS1 NO spark any help please
#1
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first. sorry if this is posted in the wrong place, pretty new to this, never had a problem with my car. Went out to my 99 LS1 cranking but no start. Was running fine the night before. My friend(mechanic) suggested the crank postion sensor. Replaced with no luck. We checked and NO spark. Is there any other things we can check. He also suggested getting a ECM any chance someone knows if that can be checked. Also recommend a cam position sensor which seems like a bear to replace any way that can be checked, I would really appreciate any help guys. She has 209,000 miles and has never given me a problem. I really need some help. Thanks
#3
TECH Junkie
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Yes, check the fuses for fuel pump & coils.
Can you hear the fuel pump prime when the key is turned?
Then, rent a noid light set from AutoZone. You get your money back when you return the set. The light will be plugged into one or more coil pack harness plugs to check for ignition/spark signal. No light, no spark.
Bad fuel pump? You can spray ether into the TB while cranking. It'll start if the fuel pump is NG.
Just a couple of things to start you.
Can you hear the fuel pump prime when the key is turned?
Then, rent a noid light set from AutoZone. You get your money back when you return the set. The light will be plugged into one or more coil pack harness plugs to check for ignition/spark signal. No light, no spark.
Bad fuel pump? You can spray ether into the TB while cranking. It'll start if the fuel pump is NG.
Just a couple of things to start you.
#4
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thanks guys I can hear the fuel pump prime and there is fuel in the rail. I have had a bad coil pack before but it still started. Fuses are also good. Thanks for the replys any other help would be great
#6
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Still get the noid lights plug in to injectors and see if the fuel injectors are being told to fire. If they are being told to fire and you have spark you can rule out crank sensor and camshaft position sensor
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#9
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Had this before, totally out of the blue. Check the coolant temp sensor on the drivers side head, I was told bad sensor = crank but no start/spark. My problem turned out to be a bad ignition relay in the fuse block, Fan #2 uses the same relay, swapped them and it started right up.
Free test and free fix... worth a try
Free test and free fix... worth a try
#10
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Had this before, totally out of the blue. Check the coolant temp sensor on the drivers side head, I was told bad sensor = crank but no start/spark. My problem turned out to be a bad ignition relay in the fuse block, Fan #2 uses the same relay, swapped them and it started right up.
Free test and free fix... worth a try
Free test and free fix... worth a try
How true is this? Having A issue with no spark on my swap.. pcm is sending spark but the coils aren't getting it.. ground looks good fuses are good. But I have no temp sensor plugged in..