Laps at Talledega, now engine issues
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Laps at Talledega, now engine issues
Ran Vetts4vets Saturday at Talladega. Second run was more fun as speeds were a little higher. Skipped third session and headed home early because the engine had some "misfires" at higher speeds. ('08 ls3) No DTC's, just did not run right. Got about 150 miles down the road and stopped at a rest area. Engine stumbled bad and died. Noticed it running worse and worse at idle and stumbling at highway speeds as trip home progressed. DTC light came on and it began random hard misses. Eventually lost power and went into reduced power mode. luckily made it to an exit where it died and would not restart. Trailered it home the last 150 miles. Got home at 2 A.M.
Plugged the diablo into it to run trouble codes. The battery is still good but the code reader will not read anything. It just keeps saying turn the ignition on. The ignition is in the acs mode. No starter engagement at all now when I try that. It had one long crank - no start attempt last night so I'm thinking that may have locked out any more restart attempts. Any suggestions on how to get trouble codes without a code reader? First place that I want to look is connections at the PCM but without codes I'm just looking around for obvious damage to sensors or wiring. I don't think that will fix anything.
Plugged the diablo into it to run trouble codes. The battery is still good but the code reader will not read anything. It just keeps saying turn the ignition on. The ignition is in the acs mode. No starter engagement at all now when I try that. It had one long crank - no start attempt last night so I'm thinking that may have locked out any more restart attempts. Any suggestions on how to get trouble codes without a code reader? First place that I want to look is connections at the PCM but without codes I'm just looking around for obvious damage to sensors or wiring. I don't think that will fix anything.
Melting Slicks
Joined: Mar 2016
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From: Indianapolis IN
If you don't have a reader there are many auto parts locations that offer the use of one without having to purchase it. Id ask to see if you could borrow it and take it home. You may as a last resort pick one up from a local store and return it if you don't want it. Good Luck!
Last edited by User Omega; May 29, 2016 at 11:25 AM.
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From: Below the bottom of Berby Hollow, NYS
If you don't have a reader there are many auto parts locations that offer the use of one without having to purchase it. Id ask to see if you could borrow it and take it home. You may as a last resort pick one up from a local store and return it if you don't want it. Good Luck!
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I appreciate all responses. I have a diablo tuner. I was able to get the scanner to read codes a few minutes ago. The engine actually cranked after we unloaded the car. It's in my shop now. The diablo tuner stated
"1 code". It will not show the code. I do not want to clear it yet. Going straight to fuel pressure and pcm connections. Any other suggestions where to start. Again I have one code but cannot see what it is.
"1 code". It will not show the code. I do not want to clear it yet. Going straight to fuel pressure and pcm connections. Any other suggestions where to start. Again I have one code but cannot see what it is.
Le Mans Master
Joined: May 2016
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From: Florida
I appreciate all responses. I have a diablo tuner. I was able to get the scanner to read codes a few minutes ago. The engine actually cranked after we unloaded the car. It's in my shop now. The diablo tuner stated
"1 code". It will not show the code. I do not want to clear it yet. Going straight to fuel pressure and pcm connections. Any other suggestions where to start. Again I have one code but cannot see what it is.
"1 code". It will not show the code. I do not want to clear it yet. Going straight to fuel pressure and pcm connections. Any other suggestions where to start. Again I have one code but cannot see what it is.
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More information. The fuel pressure is 62 psi. Oil pressure normal.
One of the issues that I'm looking for is the erratic control of the starter. Engine will spin sometimes and stop when I release the button. Then sometimes it will try to recrank the engine on it's own if the engine does not start on the first attempt. In other words, spin the engine, no start and the starter disengages on it's own then without hitting the button again it tries to restart the engine. Almost like a short in the wiring. But the starter issue, I think, is only happening because of another issue. If the engine does start, it runs OK for a few seconds then dies or quickly seems to loose ignition of fuel. Just like last night on the interstate, engine shuts down but quickly reengages. But the reduced engine power shows other issues also.
Does the BCM control the starter and ignition circuits?
One of the issues that I'm looking for is the erratic control of the starter. Engine will spin sometimes and stop when I release the button. Then sometimes it will try to recrank the engine on it's own if the engine does not start on the first attempt. In other words, spin the engine, no start and the starter disengages on it's own then without hitting the button again it tries to restart the engine. Almost like a short in the wiring. But the starter issue, I think, is only happening because of another issue. If the engine does start, it runs OK for a few seconds then dies or quickly seems to loose ignition of fuel. Just like last night on the interstate, engine shuts down but quickly reengages. But the reduced engine power shows other issues also.
Does the BCM control the starter and ignition circuits?
Drifting
Joined: Oct 2010
Posts: 1,513
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From: Rocheport Missouri
More information. The fuel pressure is 62 psi. Oil pressure normal.
One of the issues that I'm looking for is the erratic control of the starter. Engine will spin sometimes and stop when I release the button. Then sometimes it will try to recrank the engine on it's own if the engine does not start on the first attempt. In other words, spin the engine, no start and the starter disengages on it's own then without hitting the button again it tries to restart the engine. Almost like a short in the wiring. But the starter issue, I think, is only happening because of another issue. If the engine does start, it runs OK for a few seconds then dies or quickly seems to loose ignition of fuel. Just like last night on the interstate, engine shuts down but quickly reengages. But the reduced engine power shows other issues also.
Does the BCM control the starter and ignition circuits?
One of the issues that I'm looking for is the erratic control of the starter. Engine will spin sometimes and stop when I release the button. Then sometimes it will try to recrank the engine on it's own if the engine does not start on the first attempt. In other words, spin the engine, no start and the starter disengages on it's own then without hitting the button again it tries to restart the engine. Almost like a short in the wiring. But the starter issue, I think, is only happening because of another issue. If the engine does start, it runs OK for a few seconds then dies or quickly seems to loose ignition of fuel. Just like last night on the interstate, engine shuts down but quickly reengages. But the reduced engine power shows other issues also.
Does the BCM control the starter and ignition circuits?
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Why would the code reader show that I have one trouble code and not be able to show what it is and it cannot clear the code? It may be a hard code so it cannot clear it, but what code would not be available for the code reader?
Team Owner
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From: Southern Utah
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Checked those easy to see things last night while waiting for a trailer. Starter wires are fine. PCM and BCM wiring is good and clean. Sometimes it starts and sometimes it just spins and sometimes it does nothing.
Race Director
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From: T-Town WA
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Thinking the PCM has an issue. Intermittent problems and a wide range of problems. It's not the starter or connections, those wires are only for the starter power feed. Gona look inside the fuse box and after that, PCM. Should be able to buy a new PCM for about $300. Should be able to buy a new PCM and not have to program it. Am I correct on that?
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Le Mans Master
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From: Atlanta GA
Thinking the PCM has an issue. Intermittent problems and a wide range of problems. It's not the starter or connections, those wires are only for the starter power feed. Gona look inside the fuse box and after that, PCM. Should be able to buy a new PCM for about $300. Should be able to buy a new PCM and not have to program it. Am I correct on that?
Dave
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Yes, an open circuit, or bad connections in all the associated connectors. But also looking for any chaffing of wires. Covered most of that today. Can't do much else right now.
Does the starter circuit go through the ECM? It works erratically.
Can't remove the diablo tune that is installed. No communication from the car to the tuner right now, but that is random. It might work the next time I go out to the shop. The starter function does not work now and when in the acc mode, the fuel gauge does not read. It cranked a few times earlier today.
Does the starter circuit go through the ECM? It works erratically.
Can't remove the diablo tune that is installed. No communication from the car to the tuner right now, but that is random. It might work the next time I go out to the shop. The starter function does not work now and when in the acc mode, the fuel gauge does not read. It cranked a few times earlier today.
Team Owner
Joined: Mar 2008
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From: Southern Utah
Yes, an open circuit, or bad connections in all the associated connectors. But also looking for any chaffing of wires. Covered most of that today. Can't do much else right now.
Does the starter circuit go through the ECM? It works erratically.
Can't remove the diablo tune that is installed. No communication from the car to the tuner right now, but that is random. It might work the next time I go out to the shop. The starter function does not work now and when in the acc mode, the fuel gauge does not read. It cranked a few times earlier today.
Does the starter circuit go through the ECM? It works erratically.
Can't remove the diablo tune that is installed. No communication from the car to the tuner right now, but that is random. It might work the next time I go out to the shop. The starter function does not work now and when in the acc mode, the fuel gauge does not read. It cranked a few times earlier today.
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Just successfully removed the diablo tune and reinstalled the factory. Tomorrow I start looking for a new ECM/PCM. Diablo tune was removed in the acc mode. The start circuit is dead. When it does start, it runs bad for a few seconds and dies. Only one code and I still don't know what it is. Who agrees ECM?
Race Director
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From: Peoria/Phoenix AZ
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Yes, an open circuit, or bad connections in all the associated connectors. But also looking for any chaffing of wires. Covered most of that today. Can't do much else right now.
Does the starter circuit go through the ECM? It works erratically.
Can't remove the diablo tune that is installed. No communication from the car to the tuner right now, but that is random. It might work the next time I go out to the shop. The starter function does not work now and when in the acc mode, the fuel gauge does not read. It cranked a few times earlier today.
Does the starter circuit go through the ECM? It works erratically.
Can't remove the diablo tune that is installed. No communication from the car to the tuner right now, but that is random. It might work the next time I go out to the shop. The starter function does not work now and when in the acc mode, the fuel gauge does not read. It cranked a few times earlier today.
Although rare, you might check plugs to see if the iridium tips are still there and could be the initial cause of misfires.
Once you run out of self-diagnose choices, pay someone to check codes with a tech II or equivalent before spending anything for the parts swapping routine.