Rattling When Stepping On Gas?

[CSRMarc]

The dealer said the same thing when it gets hot the metal expands but they couldn't find where it was due to the metal expanding. They told me it was sealing the leak but to me I heard it more when it got hotter, may have been in my head.
When they did the cold start the next morn. they said they could hear excactly where it was coming from.
I don't know what would have caused it, but it's fixed. I sure would like to know though.

Curious on how they found out what was causing yours and what did they do to fix the misfire?

Thanks,
Marc

 

[Dr. Overkill]

Curious on how they found out what was causing yours and what did they do to fix the misfire?

My dad helped me diagnose that misfire. Luckily it had set a code that narrowed it down to cyl #3, so that really narrowed down the search. I cranked the engine over while he tested the spark and we determined that the problem was in the dizzy cap.

I had a new dizzy installed a month or two prior, and apparently one of the "circuits" inside it for the #3 cylinder had developed a break. Installed a new cap and all was well.

(Then another month or two later it developed another misfire that did NOT set a code, and I found that the terminal inside the coil had corroded and had a lot of white crud in it. I cleaned it up and it got rid of the misfire. That was my stock coil, with over 130k miles on it, so I decided to go ahead and replace it. The first one I put in--a NAPA Echelin--caused my truck to lose 2.5 MPG. I put my old one back in and got over 2 MPG back. Just last week I replaced it again with a new AC Delco coil and will see how my mileage does.)

_dennis