Sputtering and Struggling to Accelerate

Gavin_Danitz

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I need help diagnosing my car. Fbo, e30, rv6 turbo. I noticed that my car was sputtering when I left this morning. I thought it was either the head gasket or bad fuel. Found no leaks, no codes, normal temps, fuel trims, and knock control. I had a quarter tank and filled it with Sunoco 93 thinking it might be fuel but that didn’t work. I reflashed my tune thinking it might be electrical but no luck. I pulled the spark plugs and they seemed fine upon inspection. I have no idea what’s going on at this point.
 
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Gavin_Danitz

Gavin_Danitz

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I really don’t run ethanol very often but that’s a good idea. Has anyone experienced this?
 

xXoVrKiLLXx

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Check engine flashing makes me think misfireing. I know you said you inspected them but when is the last time you checked the gap on your plugs. Log it happening it may help you identify whats going on. My bet is on plugs - coil packs or something fuel related. Checking the gap is free (Id start with a log though then post it up here so someone can take a look). Keep us posted.
 
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Gavin_Danitz

Gavin_Danitz

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I wanted to check the gap but I didn’t have a tool with me. Changed them 20k miles ago. I’ll make a log tomorrow.

Honda Civic 10th gen Sputtering and Struggling to Accelerate 44D0556D-176A-4968-AA40-3EA6F60DADED
 


LBP

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Check engine flashing makes me think misfireing. I know you said you inspected them but when is the last time you checked the gap on your plugs. Log it happening it may help you identify whats going on.
Actually, this is an excellent suggestion. Quick and free to check, assuming you already have the tools.

OP, check this first, and if the plugs are fouled or worn, you need to re-gap them, or better yet take the opportunity to replace them with new, properly gapped plugs. With your mods and tunes you really should gap the plugs more narrow than stock spec (which I think is 0.028"). Aim for about 0.025" at most down to 0.020" at the minimum, and be sure to have identical gaps on every plug.

For plugs with fine-tipped electrodes like the iridium plugs our cars come with, I highly recommend using feeler gauges to check the gaps, instead of other styles of tools. Much less risk of damaging the plugs with feeler gauges.
 

xXoVrKiLLXx

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I wanted to check the gap but I didn’t have a tool with me. Changed them 20k miles ago. I’ll make a log tomorrow.

44D0556D-176A-4968-AA40-3EA6F60DADED.jpeg
Pick up a feeler guage from the auto parts store while your at it not the round disc type though they can jack up the electrode. I use something like this https://www.amazon.com/Hotop-Blades...x=plug+feeler+gauge,aps,77&sr=8-1-spons&psc=1

Amazon has some pretty cool kits that come with a gapping tool I have one and they are decent but it was from my BT FoST and those plugs NGK 6510's ITV 24's wernt 14mm so its literally a paper weight now lol.
 

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Your fbo e30 with turbo, sputtering with misfires and your middle plugs look cleaner. I'd say head gasket. I blew a couple on fbo e30 without the turbo. If your stft and ltft are good and it's running decent enough at low power it's gotta be that head gasket. Their cooling chanel between each cylinder is bogus.
 


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Gavin_Danitz

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I’ll check the gap later. Ironically enough I ordered head studs almost 2 months ago to try and prevent a possible head gasket but it’s l been on backorder. I’ll create a data log too. Let you all know later 🙏
 

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