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Throttle body issue?

codereddew

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Car has 23k miles on it; MAK delete pipes and Lund E85R tune, but otherwise stock engine wise.

I've been having an issue where the throttle body is clicking at idle which is accompanied by a drop in spark to <10, exhaust note change, and a small twitch in the vacuum gauge as demonstrated in videos below (may need headphones to hear exhaust note change).


Throttle body clicking at idle



Spark drop to <10



Vacuum gauge movement



I've had the issue for a couple thousand miles now, so I decided to take the the throttle body out today to clean it but overall, it really wasn't dirty. I was wondering if this much "play" in the TB is normal?

TB cleaning



I've cleaned the TB, MAF sensor, and replaced the battery but this issue still remains.

Overall, car drives okay although a bit clunky with lower gear downshifts when coming to a stop (even when ABS plug is disconnected). My spark also goes negative when I'm coming to a stop and just wondering if this is normal (I never see +knockR). My STFTs can fluctuate up to approximately -10 to -15% for about 1 second when coming to a stop, but are usually <5% variance during idle or cruising (range from -5 to +3 usually), which I've read is essentially normal? My LTFTs are pretty stable @ around 0 to -2%.

TLDR;
• TB clicks at idle w/ spark drop & vacuum gauge movement
• Cleaned TB, MAF, and replaced battery but problem persists
• STFTs can fluctuate up to -15ish when coming to stop; stable at idle/cruising RPM
• LTFTs stable @ 0 to -2%
• Spark goes negative for brief moment when coming to stop, but no +knockR
• E85 physically tested & confirmed 85% ethanol content

I wanted to get some feedback from some seasoned veterans as my mechanical expertise is borderline zero. What would be the next steps to diagnose/fix the issue? I've logged and sent to Lund but they said "looks good, no revisions needed".
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codereddew

codereddew

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SHxTGUN

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When you say exhaust note changes, does your RPM fluctuate at all when idle? Can you see the needle moving at all when you get the exhaust note change/vacuum gauge movement?
 

Zrussian13

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If you search I'm pretty sure another guy just finished up a similar issue to yours with the TB clicking and had to replace it. Maybe he'll chime in here. Good luck.
 
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codereddew

codereddew

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When you say exhaust note changes, does your RPM fluctuate at all when idle? Can you see the needle moving at all when you get the exhaust note change/vacuum gauge movement?
Barely, fluctuates from like high 700s to mid 700s, so nothing too substantial
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