Lt1 hesitation/screech when starting
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Lt1 hesitation/screech when starting Completely stock 96 z28 with a rebuilt engine and 90,000 miles with an automatic transmission. When I turn the key to start it, it hesitates for a couple turns and when it finally turns on it makes a horrible screeching noise. The noise doesn't seem to come from any of the belts or anything, and the starter is relatively new. It's 2 years old or so but the car has been sitting for the past 4. But the sound was happening beforehand too, just not as bad as it is now. Any ideas on what it could be? I tried shimming the starter earlier but it didn't change much. Should I replace the starter and flex plate? Or what else could cause it
I mean obviously first thought is belt. I know when the water pump bearings start to fail they can screech, as can any other bearing like the crank bearings and such. You could try spraying a lil lube just behind each pulley in case one of them is dry and screechin. What do you mean by hesitates?
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The engine has 0 miles on it since the rebuild, so I don't think it's anything internally and it just sounds like it's coming from the starter area. And by hesitate I means it turns over a couple times and sounds like it's dying, then fires up and makes the screeching noise. But the noise goes away instantly right after the engine is started. It just sounds awful while starting.
I would have someone start it with your head under the hood to confirm weather or not it is comming from starter area or belt area, or even get under it by the starter. I would think if it had anything to do with the starter area it would do it while it was turning over before it fires right?
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Yes, that's where the hesitation comes in. Sounds like it barely engages and when it fires up that's where I was thinking the screeching came from was the starter disengaging. But I'm not 100% sure. And the mechanics shop it's at thinks it's the starter, which is why I was trying to shim it but it didn't help much.
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Well you said it sat for a couple years, so a lot of dust and **** could have got in there. Take it off and give it a lil spray of WD in there maybe? If the hesitation isn't the battery and is the starter, then no sense keeping it; just replace. Could be starter bearings too. You could also look at the starter teeth and flex plate, see if it's rubbing when disengaging. I've never had to shim any of mine...
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I just sprayed all the dust and everything out today. But it's made the same sound before and after replacing the starter as well. Unless I just got really bad luck and got another bad starter? But there definitely looks like there's some wear on the outside gears of the flexplate. And the battery is new as well so I highly doubt it's that.
Idk, I just know there is a metal shield there. If you just replaced the starter and it still does it, and is definately comming from the starter area, I'm kinda out of ideas. Then again why does it hesitate with a new batt and starter? Is there a bearing or something up in there that the flexplate/output shaft rides on that is maybe going out, causing a screetch and resistance which causes hesitation as it tries to power through the resistance? And you said the rebuild has 0 miles on it so I would be suspecting something wasn't done properly.
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I'm not to sure, but I took the cover off the flexplate. But from what I've read if I had a broken flexplate it'd be far worse with vibration, which the car doesn't have. That's why I'm so confused, plus all the other things I've read so far have different issues or the videos sound drastically different from mine. Which is why I've come here. Hopefully when I get a video of it it will be more helpful for you.and the reason I had to replace the starter in the first place was because one of the bolts snapped off inside the block. Could there be an underlying condition to that that would be causing it? To much torque from the starter or something? I'm pretty clueless right now. 
If it had too much torque it wouldn't hesitate lol. What kind of starter you put on it anyway? I just run an Advance Auto Parts reman, and it works fine. Yes, video would be a big help. Plus you need to confirm where exactly it is comming from. You may just have another shitty starter. But, what about this. Was the flex plate removed or tampered with during the rebuild, or ever for that matter? If it was improperly installed this could definately cause issues.
Yeah I mean for the moment I'd guess starter. Take it back and try another. They have a warranty right? The starter is installed correctly right? You sad something about broken bolt and shims, so is it rigged up or mounted like it should be?
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The starter isn't under warranty anymore. I got it a couple years back but since I got it I've put less than 100 miles on the car. And as for the rig, everything looks like it's right but I like to have another car to compare it to to see if anything looks off, and I don't. And can't find pics of the starter with the flexplate cover off
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Well that's definitely not the type of starter I have. Do you know if the gears fully engage with each other? Because from the looks of the wear patterns they don't appear to be fully engaging, just about halfway and the starter gears have quite a bit of wear compared to those. So from what it looks like, the starter appears to be slipping. Any idea how I could fix that?
