Pinging or Timing Chain Rattling under Heavy Acceleration, Please help me..

Ok it's a 1995 ford thunderbird LX 4.6liter V8 w/123,000miles. Now, lets say i'm at a light, and just floor it, everything will shift fine except i'll get a pinging noise-more like a tic tic tic tic tic noise. Almost like when a bicycle chain is rubbing accross the frame on the bike. This only happens when i really get on the gas. Again, driving on the highway, at around 55, and you wanna pass a car up-so you kinda hit the gas hard, i'll get the noise when accelerating. This does not happen under normal driving. I can put the pedal to the floor slowly-and this WILL NOT happen. Funny, at first i thought the idler wheel was at fault-mechanic thought so also. Then i got another guy to take a look(ex pulling into a station and letting the mechanic guess as i described the problem) and he said it's most likely the timing chain, and basically don't be so rough on the car. He said if the timing is off, that when your flooring it, it's making that chain tic tic noise cause it's not timed right. Could this be the problem?? Is it that major?? I really got NO money to start fixing things, just enough for my next insurance payment.

ps.. once again, that is the only time it will tic tic, normal driving this car is a beauty. Another thing, the noise is not that loud, just enough to hear it. And it's coming from the front drivers side of the block. This noise doesn't happen when i rev it up high either.

please folks if you have any input to this, tell me. I'm a bit worried.

It can be your timing chain But I thought Ford did away with timing chains in the 80's and moved to belts.( I could be wrong.) Does the bog down as you punch the pedal down? Can you pin point the noise, while the car is parked and you punch the pedal down OR does it only happen while driving?

Hey bm2boats, thanks for responding. It only happens when the car is floored at any time. Especially when i'm on the highway, and quickly accelerate from like 55-80. It doesn't happen at idle at all, even if revved high. And yes, this 4.6 ford does still have timing chains inside the block, but also one belt outside for all the pulley's etc. As far as bog down, no no, this baby sets you in your seat when pushed. I wonder if it is spark plug knock? If it was that, wouldnt it make the noise at idle??

my guess is it is your Timing Chain. I know When I had a Ford back in the early 80's, I blew a timing chain. Not fun stuff, I know. Get it fixed now before it POPS and screws your Valves all up.

actually it sounds very much like a engine knock. It wont happen at idle, unless its really really bad i suppose. What octane gas do you purchase? If its 87, or 89, try buying 93. Engine knock does not actually sound like someone knocking on the door or something. It sounds very much like what you describe, a chain or something similar hitting hollow metal. You may only be starting to have this problem now because as your car ages, the compression ratio can, and does increase, so you will in turn need a higher octane rating gas. Try it, its an easy fix, although with the prices these days....

Hey timberdoodle, thanks alot man, the 93 fixed my knock/pinging. It's gone about a good 80%. I got the tank down to like 90% empty, then filled her up on the 93. Over two days driving, got it down to a half tank, then filled her up again with 93. I also notice a power differance, it seems to be more peppy but i think thats cause "i think" it does.

Also put in a bottle of chevron w/techron today. In the past, this stuff always helped me. BTW, i did find out that i do have minor spark plug knock, gonna get it tuned next week sometime. I'll here alittle tick tick tick tick tick when the car is running, and the hood is open. It's coming from the top/back of the engine(last spark plug).

Anyway, i'm gonna stick with 93 it's worth it, thanks alot..

no problem man, glad to hear it solved your problem. Tune ups never hurt anybody so that is a good idea. Good luck with it.