Very rough idle at cold start
#21
It is more of a preventative maintenance procedure than a fix, though.
The BG44 or Techron Concentrate fuel additive in an almost empty tank (again, use as directed!) would serve better to clean the inner workings of the injectors.
#22
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#23
So I reset my codes and took the car out for a drive to see if I got any codes. It looks to me that something is wrong with the passenger bank 1 side of he motor. Either spark plug, injector, or vacuum leak or? I drove it for 10 minutes before it threw the codes. Besides the codes it seemed to run fine except for the usual rough idle at cold start. I am just learning how to read the freeze frame data. Anybody see anything wrong with the data??
#24
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#25
#27
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If the situation is not corrected, catalyst damage is the result with DTCs P0420 and or P0430 being set turning on the MIL.
#28
How do if find out which injectors are sticking? Can a run something throu the gas? I already ran a 20oz bottle of Chevron Concentrate Plus last week with a fuel tank of gas. What else can I use to clean the injectors? I suspect the carbon clean process earlier in this thread is not the solution since that would cause "blocked' injector and a lean condition not a rich condition ?
#29
#30
So I recently started the car and it did this. Keep in mind that usually it runs great except for rough cold start. It has done similar to what I caught on the video one time before.
Here is the youtube shortcut. https://youtu.be/t5zC4-INHr4
Here is the youtube shortcut. https://youtu.be/t5zC4-INHr4
#31
Originally Posted by omegac1
I already ran a 20oz bottle of Chevron Concentrate Plus last week with a fuel tank of gas.
You need to follow the directions (yeah, who reads those). Pour the concentrate into a nearly empty tank of gas, drive for 20 miles or so, then fill the tank. THAT is how it works best. (same for BG44 too)
Fuel additives are more for preventative maintenance than for resolving issues, though.
#32
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#35
I appreciate the various comments. Keep in mind that the car usually starts fine with only minor shaking.Running like the video shown is very rare. It has only cold started that bad twice in the last 4 months. Once it warms up it idles and runs smooth as butter. Therefore the issue must be something intermittent. For example, in the video, after a few minutes the car was idling okay and Ieven took it out for a drive and it ran great. There were no dead cylinders etc. However, It does seem to idle worse on a cold start after it has sat for a few days vs started every day.
Could it be a bad injector(s) that has some crud in it and sometimes sticks open and sometimes works okay? How would I narrow it down to a particular injector? Would the CRC clean the carbon treatment or BG with almost empty fuel tank fix a stuck open injector or should I just bite the bullet and replace all the injectors? I read in other threads that replacing these injectors is a common issue?
Could it be a bad injector(s) that has some crud in it and sometimes sticks open and sometimes works okay? How would I narrow it down to a particular injector? Would the CRC clean the carbon treatment or BG with almost empty fuel tank fix a stuck open injector or should I just bite the bullet and replace all the injectors? I read in other threads that replacing these injectors is a common issue?
#37
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#38
I am trying to determine if I need to replace the injectors on both banks or just bank 1. I want to avoid double the cost and repair time if one of the banks injectors do not need to be replaced. I just bought a Bluedriver Bluetooth Pro real time scanner to see what it tells me. Attached is some "interesting" live data captures. This is my first live scanner so I need some help interpreting the data. I think that the first picture shows the Bank 2 O2 senor moving from lean to rich by the PCM as expected but the Bank 1 O2 sensor seems to be all over the place? The second picture includes the ST trims and it also shows the B2 trims look reasonable but the B1 trims are all over the place. Can someone help me if this data points to some injectors leaking and/or which if not both banks need to be replaced?
#39
Disclaimer these are just my thoughts, I am not a certified Jag tech. Take my comments accordingly.
First, your code indicates an issue with your O2 sensor being stuck rich. Is there any chance a bad O2 sensor is doing some of this? I’m thinking your heated O2 sensor (sensor 3) isn’t heating properly. After your car warms up it works better as it is heated by the exhaust instead of the electronic heating mechanism. Could always swap o2 sensors between bank 1 and 2 and see if the code follows.
Second, both banks are reading rich according to your LTFTs. Therefore I would guess an air restriction is at play (could be high fuel pressure but that seems unlikely). Therefore I would change your air filters for sure and clean your MAFs as that is cheap and rules out the simplest problems.
Best of luck.
First, your code indicates an issue with your O2 sensor being stuck rich. Is there any chance a bad O2 sensor is doing some of this? I’m thinking your heated O2 sensor (sensor 3) isn’t heating properly. After your car warms up it works better as it is heated by the exhaust instead of the electronic heating mechanism. Could always swap o2 sensors between bank 1 and 2 and see if the code follows.
Second, both banks are reading rich according to your LTFTs. Therefore I would guess an air restriction is at play (could be high fuel pressure but that seems unlikely). Therefore I would change your air filters for sure and clean your MAFs as that is cheap and rules out the simplest problems.
Best of luck.