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Tomlouns

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You said you have a misfire... but your not getting any codes? If you are not getting codes or a flashing CEL then what you are feeling is not a misfire...

Get what your feeling on a log and send to your tuner,




Yep that was my meth kit
really... I was wondering why there are no codes... when first starting off it sputters / sometimes a knock / then kicks in hard... if I aply the gas really slow I can avoid the sputter... on wet roads it goes from sputter to ripping tire... it also has very long hot start... I will keep everyone posted on what I hear from PBD. Older logs from 3 weeks ago were fine and the car ran fine...
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Totally possible you have multiple issues.
Hmmmm...Voltage booster....
Get the car into long hot start condition.
Bypass the voltage booster and try simply starting on the stock pump alone?
Pull the pump hat and check for debris?

Car is garage or street parked?
 

Notagain

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Man for the random hail marry troubleshooting in here.

A. check the gap on ALL the plugs. simple and free.
B. Log the car find out what cylinders are misfiring. Simple and free.
C. Monitor the fuel trims and see if one or more are skewed compared to others they should all be close. This will determine if its a fuel issue.


Lastly if you can data log trouble shooting can be easy and damn near free but for the love of god not random guesses. It must be methodical and one step at a time.

Edit. Reread this again and I think you need to check fuel pressure. Is it dropping off while driving?
 
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Tomlouns

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Man for the random hail marry troubleshooting in here.

A. check the gap on ALL the plugs. simple and free.
B. Log the car find out what cylinders are misfiring. Simple and free.
C. Monitor the fuel trims and see if one or more are skewed compared to others they should all be close. This will determine if its a fuel issue.


Lastly if you can data log trouble shooting can be easy and damn near free but for the love of god not random guesses. It must be methodical and one step at a time.

Edit. Reread this again and I think you need to check fuel pressure. Is it dropping off while driving?
A. check and even put new plugs in...
B. I can take the logs but don't know how to read them... They are attached at the beginning og the thread.
C. Same as B.
I like what you said about fuel pressure... How do I go about testing that? I have a DW400 with a voltage booster.
 

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Wait are you using SCT or an NGauge or what for Data logging?

I didnt catch or maybe missed what platform you are using.

I have an SCT X4 and its simple to read logs.

Those logs are gold once you figure out how to read them.
 

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Tomlouns

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SCT x4 - what is the best resource I can use to learn to read the logs? I can read what is says but I need to lean what is the expected range... for different conditions...
 
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Tomlouns

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This is the range quote for the 3rd log at the top of the page.
log pic_7037.jpg
 

Notagain

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SCT x4 - what is the best resource I can use to learn to read the logs? I can read what is says but I need to lean what is the expected range... for different conditions...
Youtube AED Sct x4 data logging shaun at AED has a few really good how to videos
 

Notagain

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This is the range quote for the 3rd log at the top of the page.
log pic_7037.jpg
Need to data log fuel trims and rpm and start with that IMO. Just my 2 cents but if it was fuel pressure the trims would be all over the place as the rpms climb and there is more load on the engine.
 
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Tomlouns

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Totally possible you have multiple issues.
Hmmmm...Voltage booster....
Get the car into long hot start condition.
Bypass the voltage booster and try simply starting on the stock pump alone?
Pull the pump hat and check for debris?

Car is garage or street parked?
Garage parked... the car has a DW400... should I reinstall the factory pump? or bypass the voltage booster with the DW400? I am also thinking about sending the pump back to DW to get the check value install... I bet they can bench test it for me... and make sure it is doing its job... do I even need a voltage booster with dw400? It was my installers idea to install it...(he thought he could tune it for e85. but once on the dyno he didn't think it had enough pressure) I wish we just stayed with the factory with a voltage booster. I am just running 93.
 

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Notagain

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Start with these 2.





Dataloggings not that daunting once you take it little at a time and realize whats going on. I think most people over complicate it and try read too many things at once so the log looks messy and crowded.
 

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Garage parked... the car has a DW400... should I reinstall the factory pump? or bypass the voltage booster with the DW400?

Im not too sure yet that pump and booster seem a little suspect but i dont know forsure what it is or isnt doing.
 

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Just saw @ugstang17's thread, could it be oil build up for you already? I don't see any catch cans mentioned for your setup.
 

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GHOST misfires are common problem with longtubes. I see it all the time. If you are sure plugs and fuel are good have them reduce misfire sensitivity and be done. This is also very common with the DW pump. It gets very hot and honestly is not a great option for what you are doing. This is what causes the hard starts.
 
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Tomlouns

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