Where to look next? Feedback/advice?
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spacecad3t
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Thinking about it more, the reason the hot idle has gone up since mucking with the TB is because I cleaned it, lol? It was dirty enough before to seal slightly better maybe...
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Tom
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Most are brass, yes, though I can't say for sure 100% whether they ever made any in another material like that. Another tell are the stampings. All of the factory plates I've seen have a number stamped on them, often the number 4...spacecad3t wrote: Sat Nov 15, 2025 11:09 amThanks Tom. Im not sure what would work ok there either... masking tape might be hard to get right. I'll wait for the other TB I have coming and try that first. It looks to have a factory plate, they should be plated yeah? Mine isn't plated looking...Tom wrote: Sat Nov 15, 2025 11:05 am I think the temp sensor is 'close enough' since the coolant is likely hotter than the outside of the motor where you are pointing the gun. I see 850 ohms which roughly equates to maybe 140F. Even if the reading were actually off by 40F, I really doubt that could cause your issue.
Kind of a hack suggestion, but I might be inclined to seal off that butterfly-to-bore gap (packing tape?) to see if that's where the air is getting by at idle. The plate looks replaced and there is some curious scratching near the bypass port -- all of which makes me suspicious of that throttle body...
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spacecad3t
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Ah brass, sorry- well mine does have a "4" stamped on it, but on the manifold side. I notice on others it's always(?) in the front?
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spacecad3t
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For what its worth, I realized I left out the photos from the DME testing.Tom wrote: Sat Nov 15, 2025 11:05 am I think the temp sensor is 'close enough' since the coolant is likely hotter than the outside of the motor where you are pointing the gun. I see 850 ohms which roughly equates to maybe 140F. Even if the reading were actually off by 40F, I really doubt that could cause your issue.
Kind of a hack suggestion, but I might be inclined to seal off that butterfly-to-bore gap (packing tape?) to see if that's where the air is getting by at idle. The plate looks replaced and there is some curious scratching near the bypass port -- all of which makes me suspicious of that throttle body...
This is where I got 0.75 k-ohms, sorry, it was the first value I saw. Then 0.78 and then my videos of 0.85
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Did someone previously rebuild the throttle body and put the plate in backwards? The edges might have a slight bevel which is keeping it from closing completely if installed upside down.spacecad3t wrote: Sat Nov 15, 2025 12:06 pm Ah brass, sorry- well mine does have a "4" stamped on it, but on the manifold side. I notice on others it's always(?) in the front?
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Tom
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I had that same thought...944er wrote: Sat Nov 15, 2025 3:41 pmDid someone previously rebuild the throttle body and put the plate in backwards? The edges might have a slight bevel which is keeping it from closing completely if installed upside down.spacecad3t wrote: Sat Nov 15, 2025 12:06 pm Ah brass, sorry- well mine does have a "4" stamped on it, but on the manifold side. I notice on others it's always(?) in the front?
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Tom
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The 4 is on the front on the two throttle bodies I just checked.spacecad3t wrote: Sat Nov 15, 2025 12:06 pm Ah brass, sorry- well mine does have a "4" stamped on it, but on the manifold side. I notice on others it's always(?) in the front?
I have the opposite issue. My idle is struggling to stay running. It starts fine for about 5-10 seconds than it starts to cough up and almost die out. Sometimes the idle comes back alive then starts the cycle again.
Following this thread since it’s giving me a lot of ideas to look at.
Following this thread since it’s giving me a lot of ideas to look at.
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spacecad3t
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Start a thread! Happy to contribute to the braintrust. Sounds like fuel delivery on your part...Efren wrote: Sun Nov 16, 2025 7:14 am I have the opposite issue. My idle is struggling to stay running. It starts fine for about 5-10 seconds than it starts to cough up and almost die out. Sometimes the idle comes back alive then starts the cycle again.
Following this thread since it’s giving me a lot of ideas to look at.