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Discussion Starter #1
I have had this issue for a while now, and the person I took my car to has never fixed it. The car will start and die twice, then it doesn't start. It will turn over but doesn't start. I can't figure out what causes this in the car. Any help is appreciated, if you need anymore information let me know.
 

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Do the basics like checking to see if you have spark, fuel, and compression. You can't know where to start if you don't know what you're missing.
 

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Discussion Starter #5
Do the basics like checking to see if you have spark, fuel, and compression. You can't know where to start if you don't know what you're missing.
The car will start and stay on if I give it gas, so it has all the requirements to start, and run, but once you let off the gas it will die.

Is there an engine light on?
Check engine light has been on since I got the car, but I think it is an electrical issue. Codes for the O2 sensors, but all the o2 sensors have been replaced on the car.
 

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Check engine light has been on since I got the car, but I think it is an electrical issue. Codes for the O2 sensors, but all the o2 sensors have been replaced on the car.
So there are still codes? What are they? You may need to record your LTFTs, see to your possible electric issues, possible exhaust leaks (as they can affect O2s), ECU capacitor degradation, and vacuum leaks.

You aren't painting a complete enough picture for us to help you.
 

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So there are still codes? What are they? You may need to record your LTFTs, see to your possible electric issues, possible exhaust leaks (as they can affect O2s), ECU capacitor degradation, and vacuum leaks.

You aren't painting a complete enough picture for us to help you.
Exactly. I wouldn't dismiss engine codes as simply electrical issues. O2 codes don't always mean the O2 sensors need to be replaced. Sometimes there are other issues that are causing the problem and those issues could be causing your engine to not run correctly.
 

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So there are still codes? What are they? You may need to record your LTFTs, see to your possible electric issues, possible exhaust leaks (as they can affect O2s), ECU capacitor degradation, and vacuum leaks.

You aren't painting a complete enough picture for us to help you.
Here is the Data I have from the scanner I have to monitor the car. The P0171 is odd because my car guzzles fuel like crazy, and the MAF has been replaced as well. I checked the wires that are easily accessible and didn't see and fraying so I am at a loss.
If you need anything else as I said just let me know.

42952
42953
 

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If it's reading lean and it's consuming too much fuel, that O2 sensor likely isn't functioning correctly. I'd track down the malfunction in the O2 circuit and see if that fixes your problem.
 

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Also I should have noted this before, but bank 1's LTFT is pegged at max. I bet you that whatever is causing that is your problem. For future reference, the fuel trims for the different banks should be similar. Not necessarily equal, but at least close. Bank 1 is pegged positive while bank 2 is negative. That's a red flag.
 

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Also I should have noted this before, but bank 1's LTFT is pegged at max. I bet you that whatever is causing that is your problem. For future reference, the fuel trims for the different banks should be similar. Not necessarily equal, but at least close. Bank 1 is pegged positive while bank 2 is negative. That's a red flag.
Do you know what the average Fuel trim is on the eclipse?
 

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Do you know what the average Fuel trim is on the eclipse?
I don't think there is one. It's based on the condition of your fuel system and engine and the stacking of manufacturing tolerances your car ended up with from the factory. Also depends on fuel quality and ambient temperature. Only thing that is constant is that the max long term trim is 12.5% if I remember correctly.
 

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If it starts and you can keep it running with your foot on the gas but dies at idle, you have a major vacuum leak. It could be the brake power booster or the seal on the shaft for the intake manifold butterflies. I've had to fix that on my GTS more than once. I replaced the little seal with an o-ring packed with grease.
 

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Ok, there is a lot going on with your logs. It unfortunately brings up more questions that I have to ask. When this log was taken: 1) had the ECU been reset recently (unplugging the battery terminals)? 2) verifying you were driving the car since your speed was 60, your engine load was 85, and your temp was 79. Yes?

Based on your log, the LTFT are f'ed. Super lean on one side and super rich on the other. And obviously that's from all your O2 sensor codes. You've got to solve those codes. Otherwise the engine will never run properly in close loop.

If the car is drivable, I may want you to do a 'clean' log. This involves resetting the ECU (disconnect both terminals from the battery and touch them together for a few seconds. This drains the capacitors in the ECU and prevents any data and codes from being stored.) Start the car and keep it idling until it gets to operating temp. (180* F). Observe and note your long term fuel trims at idle or close to idle... if you gotta keep it running with your foot on the gas slightly. Then take it for a drive. Preferably on a highway where you're not changing gears and you're maintaining between 2500–3500 rpms. I want to see a snapshot of the log with the above condition. Hopefully your car is drivable. The numbers will be likely the same but I want to see corresponding load, engine temp, speed and codes under normal circumstances.
 

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Taking things further: I would flash my ECU disabling close loop. This takes the O2 sensors off-line and your car refers to the fuel and ignition maps only. This is an advanced process that requires ECU flash and the proper Tactrix flashing cable.
 

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Discussion Starter #17
If it starts and you can keep it running with your foot on the gas but dies at idle, you have a major vacuum leak. It could be the brake power booster or the seal on the shaft for the intake manifold butterflies. I've had to fix that on my GTS more than once. I replaced the little seal with an o-ring packed with grease.
Ok, there is a lot going on with your logs. It unfortunately brings up more questions that I have to ask. When this log was taken: 1) had the ECU been reset recently (unplugging the battery terminals)? 2) verifying you were driving the car since your speed was 60, your engine load was 85, and your temp was 79. Yes?

Based on your log, the LTFT are f'ed. Super lean on one side and super rich on the other. And obviously that's from all your O2 sensor codes. You've got to solve those codes. Otherwise the engine will never run properly in close loop.

If the car is drivable, I may want you to do a 'clean' log. This involves resetting the ECU (disconnect both terminals from the battery and touch them together for a few seconds. This drains the capacitors in the ECU and prevents any data and codes from being stored.) Start the car and keep it idling until it gets to operating temp. (180* F). Observe and note your long term fuel trims at idle or close to idle... if you gotta keep it running with your foot on the gas slightly. Then take it for a drive. Preferably on a highway where you're not changing gears and you're maintaining between 2500–3500 rpms. I want to see a snapshot of the log with the above condition. Hopefully your car is drivable. The numbers will be likely the same but I want to see corresponding load, engine temp, speed and codes under normal circumstances.
Currently it is not starting, I think the Engine Immobilizer is stopping it, I am going to pull the battery cables off tomorrow to see if that will reset it, and it currently dies immediately after starting, so I need to get that fixed. Then I can get the information you need.

The ECU has been recently reset, I had to change the battery. the car sat dead for a couple weeks.

Taking things further: I would flash my ECU disabling close loop. This takes the O2 sensors off-line and your car refers to the fuel and ignition maps only. This is an advanced process that requires ECU flash and the proper Tactrix flashing cable.
Do you know of a good place to get the Flash cable?
 

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Do you know of a good place to get the Flash cable?
I'll give you the link, but after thinking about it, you have a lot of work to do before you starting messing with the programming of the ECU. You can actually make things worse. The PO 134 "..No Activity..." means you got a short/open circuit some where. Get a multi-meter/circuit tester and start checking the harness connectivity. Check from where the harness connects to the ECU and where the signals are supposed to terminate. If the O2s are new, you can check the resistance to make sure they didn't fail. Its going to be a lot of work. All the info you need are in the manuals.


A smoke machine would be good to check for vacuum leaks. After all the electrical checks, this is what I would check next.

Just know, you can brick your ECU if you start flashing it incorrectly. You shouldn't start here. Be careful!

 

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I'll give you the link, but after thinking about it, you have a lot of work to do before you starting messing with the programming of the ECU. You can actually make things worse. The PO 134 "..No Activity..." means you got a short/open circuit some where. Get a multi-meter/circuit tester and start checking the harness connectivity. Check from where the harness connects to the ECU and where the signals are supposed to terminate. If the O2s are new, you can check the resistance to make sure they didn't fail. Its going to be a lot of work. All the info you need are in the manuals.


A smoke machine would be good to check for vacuum leaks. After all the electrical checks, this is what I would check next.

Just know, you can brick your ECU if you start flashing it incorrectly. You shouldn't start here. Be careful!

I agree with this. Fix your codes first and see where it gets you. No need to change anything with the ECU when it's clearly showing faults. If it weren't showing any DTCs, then I'd say start playing with the flash for diagnostics, but that's absolutely not necessary right now and could actually make things more difficult.
 

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Discussion Starter #20
I'll give you the link, but after thinking about it, you have a lot of work to do before you starting messing with the programming of the ECU. You can actually make things worse. The PO 134 "..No Activity..." means you got a short/open circuit some where. Get a multi-meter/circuit tester and start checking the harness connectivity. Check from where the harness connects to the ECU and where the signals are supposed to terminate. If the O2s are new, you can check the resistance to make sure they didn't fail. Its going to be a lot of work. All the info you need are in the manuals.


A smoke machine would be good to check for vacuum leaks. After all the electrical checks, this is what I would check next.

Just know, you can brick your ECU if you start flashing it incorrectly. You shouldn't start here. Be careful!

Yes, of course, the first priority is to get those fixed, fixing those could very well make the car run better, I want to do that, then clear the ECU again and check the fuel trims.
 
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