I was sitting in a mcdonalds parking lot the other day. I have an lg4. I gave it some gas before I went to start it so It would start like normal. After I gave it some gas I let off of the petal and turned the key. And HOLY CRAP, at first I thought that the high idle kicked on but it kept going. I realized my throttle was stuck and kicked at the throttle pettle to stop it but by the time it became unstuck it had tapped 5500(redline being 5000). It went down to idle and I put it in reverse. It was running rough(kind of like it was loping from a cam) but I was not sure if it was damaged or not because my car sometimes seems to do that when cold. But.... it was worse than that. When I took off it still drove. I drove out into the road and when it shifted into second it seemed to bog and die. I started it back up and heard what I thought sounded like rod nocking and so I coasted into walmart parking lot which was less than a block down the road. I just kind of left it in the parking lot. When I talked to one of my friends dads, he said that the fact that it was running rough made him wonder what happened. He said that it could have floated the valves or even just nocked some carbon loose from revving higher than normal. What do you guys think. Would it hurt it to start it up and let it idle even if a rod is knocking. I am not to worried about the 305, I am about to buy a 350 to put in it temporarily whether it is bad or not. I just dont want to put a hole in the block or anything. Sorry about the length of this post but I need help here.

Thanks

Ben

 

5500 is nothing for a SBC bottom end. I would not worry about a rod knock unless it was already on its last leg. If it still has oil pressure, then none of that is hurt.

More likely, it backed a rocker nut off or broke a rocker or a stud or something like that in the valve train. It doesn't sound from your description like anything terribly serious. You might want to determine where the noise is coming from, then pop a valve cover or whatever and look at the source of it and go from there.

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"So many Mustangs, so little time..."
ICON Motorsports

 

So you think it would be safe to start it to see where the sound is coming from then?

Thanks

 

Ummm, yeah... if it's toasted, then it doesn't matter if you start it; if it's not toasted then it doesn't matter if you start it... of course, you'll either tear it up worse, or do nothing at all to it, so that would be a 50% chance of either occurrence

But seriously, you'll have to start it (or at least try to) to figure out what's wrong. Just have a plan, and examine carfully what information is available to you, and you'll be able to figure out pretty quick whether the motor is fried or not. Like I said, check for oil pressure, that's the key indicator: if it's got that when it gets warmed up, then the bottom end is definitely OK (probably is).

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"So many Mustangs, so little time..."
ICON Motorsports

 

Well, I just started it. It runs but not well. It would keep running on its own to start with, but after a couple of minutes it started to try to die. After that it did. I restarted it but it would not run without me tending to the pedal. It was making a noise that I think that I could best describe as a clack. I tried but could not tell where the noise was coming from. It almost sounded like it was coming from whichever side you were on at the time. It is also kind of hard to tell because my car is kind of loud its self because it has no muffler or cat. It sounded kind of like the top of the motor but I couldnt say for sure. It was kind of inconsistant. It would come and go at idle but it would comback pretty quick if you raise the rpms a little. Does this help any.

Thanks

 

Oh yeah, I forgot, it does have oil pressure. It is running about normal. If anything it may have been a little higher than normal but that could be my imagination.

Thanks

[This message has been edited by Momar (edited December 06, 2001).]