LT1-- intermittent hard starting
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From: Bagpipes put the "fun" in "funeral"
LT1-- intermittent hard starting
This has happened the past couple of cold starts.
Initially, I'll turn the key to engage the starter, and it'll turn the engine over once and then stop. It's as if the starter suddenly hits a dead spot and isn't getting any more power. But then on the second try it fires right up and the engine runs normally. This hasn't happened on warm starts.
Voltage is 12.6 with the engine not running, and 14.6 with the engine running and the battery is less than a year old.
Is my starter on the way out, or could this be something else? About 90k miles on the odo.
Initially, I'll turn the key to engage the starter, and it'll turn the engine over once and then stop. It's as if the starter suddenly hits a dead spot and isn't getting any more power. But then on the second try it fires right up and the engine runs normally. This hasn't happened on warm starts.
Voltage is 12.6 with the engine not running, and 14.6 with the engine running and the battery is less than a year old.
Is my starter on the way out, or could this be something else? About 90k miles on the odo.
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From: Mexico Beach FL
Re: LT1-- intermittent hard starting (Thud)
These were the exact symptoms I had when my Opti-Spark was carbon tracked. The carbon track allowed the next cylinder in the firing sequence to fire against the starter prematurely while the piston was coming up.
Tom Piper
Tom Piper
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From: Bagpipes put the "fun" in "funeral"
Re: LT1-- intermittent hard starting (Tom Piper)
These were the exact symptoms I had when my Opti-Spark was carbon tracked. The carbon track allowed the next cylinder in the firing sequence to fire against the starter prematurely while the piston was coming up.
Tom Piper
Tom Piper
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From: Mexico Beach FL
Re: LT1-- intermittent hard starting (Thud)
The best time to check battery voltage is under load. There are battery testers that load the battery when testing. But, for most people, it is easier to check the battery voltage while the starter is engaged. The battery voltage, measured at the battery terminals, should be at least 10 volts while the starter is engaged. If it is, the battery is OK. However, there could be a bad connection in the battery cable, etc. This would cause a voltage drop so some of the voltage is not available right at the starter.
Tom Piper
[Modified by Tom Piper, 11:48 AM 11/15/2001]
Tom Piper
[Modified by Tom Piper, 11:48 AM 11/15/2001]
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From: Bagpipes put the "fun" in "funeral"
Re: LT1-- intermittent hard starting (Tom Piper)
The best time to check battery voltage is under load. There are battery testers that load the battery when testing. But, for most people, it is easier to check the battery voltage while the starter is engaged. The battery voltage should be at least 10 volts while the starter is engaged.
Tom Piper
Tom Piper
Do you know of any conditions that would cause premature carbon-tracking in a new opti? The opti+wires are pretty new, the plugs have about 25k miles on them.
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From: Mexico Beach FL
Re: LT1-- intermittent hard starting (Thud)
Do you know of any conditions that would cause premature carbon-tracking in a new opti? The opti+wires are pretty new, the plugs have about 25k miles on them.
When my Opti-Spark carbon tracked, there were no trouble codes set. The only way I could confirm the problem was to take a "snapshot" of the data with the Vetronix Tech-1A scan-tool (http://www.vetronix.com/diagnostics/tech1a/). After graphing the data, I could plainly see that there was significant, but intermittent, spark retard and knock sensor detection during driving under crusing conditions. When cruising, there should be no knock. Since the problem was intermittent, I had to manually trigger a "snapshot" at the moment I felt the miss.
Tom Piper
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From: Bagpipes put the "fun" in "funeral"
Re: LT1-- intermittent hard starting (Tom Piper)
OK well so far I haven't felt a miss when driving the car, but I'm going to replace the plugs soon anyway. I still have the stock coil though.
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From: Mexico Beach FL
Re: LT1-- intermittent hard starting (Thud)
OK well so far I haven't felt a miss when driving the car, but I'm going to replace the plugs soon anyway. I still have the stock coil though.
Tom Piper
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From: Bagpipes put the "fun" in "funeral"
Re: LT1-- intermittent hard starting (Tom Piper)
OK well so far I haven't felt a miss when driving the car, but I'm going to replace the plugs soon anyway. I still have the stock coil though.
When my problem started, I had no miss, just intermittent starting problems like you mentioned. It became worse over time and eventually started missing slightly while running.
Tom Piper
When my problem started, I had no miss, just intermittent starting problems like you mentioned. It became worse over time and eventually started missing slightly while running.
Tom Piper
