94 Accord thumping noise from wheel area, dealer can't diagnose - HELP!!!

I have a 94 Accord, manual with 135,000 miles on it. Early this year (it was still winter here on the east coast) I started to see this problem - after I start the car and have driven about 4-5 miles on the
highway (the temperature gauge at midway point), a 'thug...thug...' kind of sounds starts up and I can feel the vibrations in the steering wheel and the floor. It starts off soft and then gets really loud - as thought the car is just going to go 'plunk' on the highway. I have to slow down to almost 30mph on the highway to safely get home. The sound is continuous with a frequency of 2/sec. It happens in all the gears BUT only when my foot is on the gas. It does not happen when I am coasting in gear (foot not on gas) or in neutral, say downhill. It is more prominent when the wheel is straight or turned to the right, not to the left. It does not happen if I am driving in the city or on the local streets (STOP & GO). It also seems to decrease when I get off at an exit and am back to driving at 25-30mph.
I have taken it to a Honda Dealer (O'Donnell Honda Service Center, Ellicott City, MD) 4 times.
First time then had me replace the Reman Shaft - $900 odd. I had barely driven out of the shop, and the noise started again - so I turn around and go back. They ask me to leave it in the shop. Now they say that the brake calipers are hanging and so, they replace that along with the whole brake assembly, drum etc, etc. - over $700
Then summer came along and I never heard the noise again. A few weeks ago, as it started to get cold, the problem crept up again.
I took it back to the dealer and told them that they had made me spend all this money and the problem is not gone. Since the repair was under warranty - they agreed to take a look at it. I told them that they need to drive at least 4-5 miles before they'll begin to hear the noise. I am sure they did not, they made a note on the work order, that it was raining and so they could not hear the noise. The noise again seemed to have disappeared.
Last week, 'whatdoyouknow', the noise started again. Took it back to them and this time I expressed my frustration that this is happening way too often and for them to fix it for once and all. I get a call after they 'diagnosed' it and the service rep. tells me that the exhaust is an after-market on, so the whole assembly needs to be changed. I told them that if that was the case, then it should happen all the time, plus the sound and the vibrations seem as though they are coming from the front wheel area and not from under the body of the car.
Even the Service Shop Manager could not diagnose the problem, even after expressing frustration; I got him to go on a test drive with me and demonstrated the noise. He then says it may be from the balancing of the wheel - and I know that is not the case, since I had got that done less than a year ago, plus, again, if that is the case, shouldn't it be happening all the time.
I give up - does any one here have a clue???
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Sorry for the long post, to summarize...The noise starts under the following conditions only,
After having driven 4-5 miles at highway speeds When foot is on gas All gears Outside temperature is slightly cold (less than 60 deg F) Wheel is straight or turned right
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if anyone is intersted...
turns out it was indeed the left axle. took my car this time to an independent mechanic. he put it up on the lifts and showed me the reason the sound was coming. there was quite a bit of play on the left axle, compared to none on the right-new one. his explanation as to why the sound started only after driving 4-5 miles was that it took some time for the grease in the boot to be less viscous - *who knows*. the motor mount was also cracked - but he said that there is no urgency to replace that. he changed the axle, along with the boot and we took it for a test drive - *NO SOUND* . thanks everyone - (^_^)
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Yes - we do care! The lack of responses was a measure of how much we were scratching our collective heads. Noises can be a real beast to diagnose long distance. Next time we will have something to offer.
Mike
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Michael Pardee wrote:

aint that the truth. bought a '94 Accord VTi-S last week and every time i turned the engine off, there was a dull banging noise about a few seconds after. also, when i turned the engine on, a few seconds later that thumping noise was there again. it came from behind my posi in the drivers seat and none of my workmates could work it out - I was just happy it came from the opposite direction as the engine. a workmate suggested it could be the sunroof 'motor' trying to close the sunroof even though it was closed - as a safety feature :) - but anyway, it turned out to be the rear aerial (antenna) making the noise right at the end of it's retraction... and it was happenning when the radio was turned on and off, rather than the car engine. hehe gotta love those thumping noises.
deker
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