Random Misfires

[ecjr173]

Hey guys, so I keep going through some rough starts and when I scan it I get misfires on 2,3,4. I just replaced the plugs with some NGK Laser Platinum plugs and new coil packs from ECS Tuning about 2-3 weeks ago. I have cleared the codes and it runs good. But if I let it sit for a few hours I go through the same thing. Or even if I don't clear the codes right away it's rough for about 5-10 seconds after I start it then it gets smooth and drives fine. Until I let it sit for a while. What can it be. Are those the wrong plugs. Could I have gotten bad could from ECS. Any info or tips will be appreciated.

Thanks,
Eli


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[old guy]

Clicky click®

[Seerlah]

Question: If I were to take all your informative posts and create an "internet" non-for profit E-How TO book or blog spot for it, would you sue me for copyright infringement? And what if I countersued under the precept of a false claims with malicious intent? Would you still be my friend?

[old guy]

I hereby give rights to Mitch for all of my clicky clicks to use in any format that he desires.

And yes you will still be my friend.

[ecjr173]

Well my battery is brand new. The rear coolant temp sensor was replaced about 3-4 months back. I just tried starting it up and had some hesitation. Scanned it and showed random misfires on cylinder 2 & 3. All of this really started after I did my thermostat replacement. Ran good for a few days but now keep getting the misfires.


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[Seerlah]

I hereby give rights to Mitch for all of my clicky clicks to use in any format that he desires.

And yes you will still be my friend.

[old guy]

Well my battery is brand new. The rear coolant temp sensor was replaced about 3-4 months back. I just tried starting it up and had some hesitation. Scanned it and showed random misfires on cylinder 2 & 3. All of this really started after I did my thermostat replacement. Ran good for a few days but now keep getting the misfires.

Before your next cold start check the IAT reading as well as the rear CTS reading and compare them to each other. If the car has sat overnight the two readings should match each other.

[ecjr173]

Ok. I'm not to familiar with how to take those reading. How would I do that.


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[diztek]

Before your next cold start, check spark plugs to see if there is any coolant residue. Head could be leaking. It runs rough till the coolant burns off the plugs, then it's all good. Once the car sits for a while coolant begins to get the plugs wet again and then after a few minutes of idling, the coolant burns and it runs fine.

[old guy]

Ok. I'm not to familiar with how to take those reading. How would I do that.

You can always break out the VCDS. But by far the easiest way would be to use the TorquePro app on your cell phone. TorquePro and a ELM-327 OBDII bluetooth transmitter has got to be the best $15 I ever spent. You can configure the display any way you want. Here's one of my screens that I monitor every time I drive the B6.

[IMG][/IMG]

[IMG][/IMG]

[ecjr173]

Diztek- I checked my plugs and no coolant in there so I'm good.

Old guy- is that only for android. Cause I have an iPhone.


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[old guy]

Check out engine link for iPhone. I believe it is similar to Torque Pro.

[ecjr173]

So I try to start my car just now to go to work and just as I thought I get a rough start. Took me like 4 tries just to start it and check engine light comes on. But it drives fine. Then my display starts to flash the coolant symbol and my temp needle goes up just past the 3/4 mark then goes down to normal. I will scan it in the morning and see what's up. Any more ideas. Also would the SAI pump be contributing to all of this. I know mine is going bad. I posted a video a while back about it whining at start up.

Also thanks old guy for the iPhone app info. Gonna look into carrying one of these in my car.


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[ecjr173]

I should also mention that when I was doing the thermostat replacement, I had a hard time putting the belt back on the alternator. It moved around a bit but was able to get it on. Could that also be causing this issue.


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