You could. It could be the IAC and probably is. The IAC can make some crazy noise with a big TB. Take the intake pipe off and see if it’s worse. If it is, then you can get rid of it with a throttle plate adjustment and IAC cold start setting change.
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You know you've got me thinking. That might be it. Since I have my cold air intake down in front of the left front tire the noise could be coming from down there.
If it’s way worse with the intake pipe off, then that’s it. Easily resolved with 10-15 minutes of iac tuning. The issue is that you only have 30 seconds to check it at cold start up so it will take a week or two if cold startups. Or just cheat the dang thing.
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I don't have an intake setup yet. And I only have maybe 10 minutes of run time. Last time I started her I put my hand over the throttle body and I could feel it and hear a change in the pitch. I'm not worried as stated i should be able to tune it out pretty easily. The thing that gets me is how something so small as the iac port can whistle THAT LOUD!!!!
I know exactly how you feel when you hear it. It almost seems impossible but that's physics i guess
Next time you start it cold, have the IAC steps shown in the screen, then take note of what step it’s at when the noise goes away. Then get it to run and start properly with that many steps or less.
Pulled the intake tube off. It's definitely from the throttle body. Sounded down below because that's where the air filter is located.
Open the throttle plate 1/2-3/4 of a turn. Relearn the TPS and knock your starting IAC steps in half for less than 90 degrees.
I'm assuming you have one of Holley's base tunes loaded. They make those so that they will start and run with a stock TB. So you're larger one doesn't need all of that starting air.
Also, it might be that you are really noisy at a certain step, but not over that step. If that's the case, then you make your warmup enrichment for air jump over that area so that it makes that noise for less than a second.
But it sounds like you're onto it. WAAAAAAAAAAY to go!!!! Have you tried the clutch yet?
I'm assuming you have one of Holley's base tunes loaded. They make those so that they will start and run with a stock TB. So you're larger one doesn't need all of that starting air.
Also, it might be that you are really noisy at a certain step, but not over that step. If that's the case, then you make your warmup enrichment for air jump over that area so that it makes that noise for less than a second.
But it sounds like you're onto it. WAAAAAAAAAAY to go!!!! Have you tried the clutch yet?
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Wellllll, there's a slight issue with what you want me to do. Throttle plate is completely closed, IAC reads 0%, asking for 750 rpm, will only get to 795-ish. So this goes back a little ways. The IAC would NOT fit into the t-body. Period. Like it sat nearly 1/2" off the body. IAC was a used one. I tried several others all with the same out come. Even ordered a brand new one.. Come to find out, the inner step bore was too small for the IAC housing to fit into. Ended up using a die grinder to enlarge it enough and make it fit. Also ended up hitting the opening for the pintle. Hence, unwanted airflow :/ So long story short, I might just order another t-body and start over.
Oh and no, haven't tried bleeding the clutch any more. Father's day stuff kept me from it. But that's OK. Its all worth spending time with the family!
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Throttle plate fully
Closed tells me you have an intake leak somewhere. What KPA are you idling at?
Closed tells me you have an intake leak somewhere. What KPA are you idling at?
