Need help pls..89' w/80k engine w/ knocking noise
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Joined: Oct 2001
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From: Seminole FL
Need help pls..89' w/80k engine w/ knocking noise
Just started making this knocking, pinging, clapping noise coming from the top rear of engine around distributor cap. Starts fine and runs strong when cold. I take her for a short run 20 mins or so just to keep her batt. charged and things lubed up once a week. She gets up to operating temp around 200 degrees then I put her back in the garage. The past 3 times she started making this funny noise when at idle before pulling into garage. If I rev her up the noise goes away but she runs rough and then the noise returns at idle. Never heard this sound before. Thinking maybe bad dist.cap, cross firing or coil???? Any suggestions?
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From: indy indiana
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Joined: Oct 2001
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From: Seminole FL
Thx for the replys.
1. I can have the timing checked once i've ruled out any other stuff. I don't have a timing light or know how to do it. Can't be that hard to check.
2. Yes I can pull the distributor and look for ??? I replaced it several years ago along with the coil and rotor...autozone stuff. Prob. has 2k miles on them. I was just gonna replace everything again at $54.00. I did hear a pop, like I cracked the plastic when I tightened down the last bolt that holds the distributor cap in place when I replaced it. Never checked it out and has been running fine for the past few years. Can a cracked dist.cap cause this problem?
3. Never taken a video on the phone and no clue how to post it here but can try to figure out how to do so if I can't find a simple solution.
4. I'm really busy this time of year so just trying to get some ideas from you so I have some things to check when I jump on it.
1. I can have the timing checked once i've ruled out any other stuff. I don't have a timing light or know how to do it. Can't be that hard to check.
2. Yes I can pull the distributor and look for ??? I replaced it several years ago along with the coil and rotor...autozone stuff. Prob. has 2k miles on them. I was just gonna replace everything again at $54.00. I did hear a pop, like I cracked the plastic when I tightened down the last bolt that holds the distributor cap in place when I replaced it. Never checked it out and has been running fine for the past few years. Can a cracked dist.cap cause this problem?
3. Never taken a video on the phone and no clue how to post it here but can try to figure out how to do so if I can't find a simple solution.
4. I'm really busy this time of year so just trying to get some ideas from you so I have some things to check when I jump on it.
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Joined: Oct 2001
Posts: 55
Likes: 0
From: Seminole FL
Oops, I replaced the distributor cap not the distributor. Visual check around the outside of the cap doesn't show any obvious cracks. Can't really see around back by firewall tho. Don't understand why the knocking goes away when u rev it up?? Only does it at idle. Car runs rough when reved up tho but no noise???
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