This story just keeps getting better. I couldn't make this crap up if I wanted to. About 3 hours after returning home form the dealer today I get a call from the Service Manager. He said that he and his mechanics finally heard the noise. He said he took the HOE for a road test one last time and no sooner he left the lot it started making the lifter noise. He returned to the shop and the noise stopped. He said he loaded two of his mechanics up and away they went. Less then a mile later the noise started again so he pulled over and raised the hood. He said that one mechanic crawled under the vehicle while the other checked under the hood. Again the noise stopped. They revved the engine just above idle and the noise returned. They headed back to the shop and the Service Manager called the area GM Service Representative. Here's where it gets good. The GM Rep told the Service Manager to go drive another brand new 07' Tahoe and see if he can get it to make the same noise, meanwhile the GM Rep was going to talk with GM's Engineers to get their opinions. So today was good news and bad news. The good news is finally somebody at the dealer heard the stupid noise and the bad news is they might have to tear into a brand new motor. They are planning to pull a valve cover off in the morning and use a stethoscope to pin point the noise. As always, I well keep y'all posted on this CONTINUING NIGHTMARE.

 

This afternoon the Service Manager gave me an update call. He said the GM Area Rep came by the shop and was able to hear the noise first hand. He called the GM Techs and they began researching past similar complaints and their fixes for the 07' HOES. They have discovered numerous complaints concerning the same kind of engine noise that plagues our HOE. These complaints were addressed with two types of fixes. The first one is not so bad. It's a computer update program to reprogram the Fuel Management System. According to the Techs this has fixed the tapping noise problem in several new Tahoes. The second fix is not so good. It turns out that over 10 new 07's have had a complete lifter replacement to cure the problem. So as of Friday afternoon GM is sending the new fuel management progran to the dealer but they may not have the time today to make an evaluation. We should know more by Monday afternoon when the Service Manager updates me again.

 

Tuesday August 29, 2006
This afternoon we finally get a call from the Service Manager. He said they think the problem is fixed with the tapping noise in the motor. He wants us to come and pick up the vehicle and drive it for a day to make sure. After the repairs were made he said they were unable to hear the noise after letting it run for over an hour and taking it for a short test drive. Good news I hope. Here's what was done to fix the problem. They pulled the valve covers off and found what they thought was a weak valve spring. It was replaced. Next, they serviced the complete injector system, then they changed the oil and filter. They checked the filter for debris and found none. They ran an updated computer program for the fuel management system or injector system. They also fixed the other problems we had with the A/C and the exit lighting on the outside mirrors. The cure for the A/C was a defective module and another updated computer program and the fix on the exit lighting was replacing the light sensor. I picked up the vehicle late this afternoon and drove it about 50 miles and brought it home so my wife could drive it. She drove it another 60 miles and I'm happy to report that everything if fine. She will take it to work on Wednesday and if everything checks out OK we will take back the loaner Yukon. I'm trying not to get too happy just yet, it's a wait and see thing now. One more thing i've got to say is that the Service Manager (Jeff) at Bruce Lowrie Chevrolet has been great to work with. He has done everything possible to please us. As always, I will keep y'all posted.

 

Wednesday August 30, 2006
Well we didn't have to wait too long before the noise reappeared. That's why I was reluctant yesterday to get too happy about the positive results of the repairs. Upon arriving at work this morning (about 20 miles from home) the noise was back and just as loud. My wifes coworkers knew it was her when she pulled into the parking lot. She drove it again at lunch time with the same results. This time they will tare into the engine because they have tried everything else. I'm wondering now when they go in and replace all the lifters and the noise still remains what's next? I guess we will have to cross that bridge went we get to it. Oh yeah, the exit lighting quit again but the A/C seems to be working fine for now. One fix out of three is not a very good batting average, you think? We will be leaving it at the dealership this afternoon. More to come.

 

Gman - The air appears to be working because we finally have relief from the heat. You need to test it when it gets back over 100!! Sorry to hear about your troubles, I don't know what I will do if we have the same problem we had on our vacation when we travel to El Paso in October. Keep us updated!

 

I was a wee bit apprehensive myself when you listed what the dealer told you that they did to correct the tapping noise problem.

It could be so many things, if this round doesn’t fix the problem I would ask that the mill be replaced if it were me.
We’ve seen bad spark plugs, loose exhaust manifold or head fasteners, faulty injectors, improperly seated wrist pins, bent or poorly cut valves, broken valve guides and springs, bad oil pumps, improperly machined oil galleries, improperly cut camshafts, (you name it cause) cause the noise that you describe.

 

GM Engines Are "Like A Knock"

Click the link above and read a bit. May be what you're experiencing. I don't have anything close to the noise you say you have. If your wife's friends can hear it, that's unacceptable in my book. Mine barely has a tick (and that still bugs me). Nobody else can hear it, except me.


Once again, good luck.

 

Thanks for all the support guys. TexasTahoe you're right the heat has let up some the last few days. I think it was only 89 or 90 today. Yes the A/C wasn't cooling very well but part of the trouble was the recirculate button would turn off by it's self. That part is now fixed and the A/C seems to be cooling. Like you say the real test will come when it gets over 100 again. Mr. ZX1100F1 my thoughts exactly, if this problem continues after this round of repairs I will be requesting GM put a new motor in our Vehicle. I'm sure there will be a fight but I'm losing patience at this point. sn75 I know what you are talking about. I bought a new 84' Monte Carlo and it had that little ticking noise. When I sold it there was 145,000 on the clock and it still ran fine. I wished my problem now was a little ticking noise but it's light years more then that.

Before completing this entry I checked out sn75 web-site on GM engines making noise. I played the piston slap demo and I've got to say that sounds real close to mine. But, when you have piston slap doesn't it make the noise all the time? Our sound comes and goes and it seems to be at it worst in the morning after it's sit all night. Doesn't piston slap effect the performance? Ours runs so smooth and the fuel milage is better then some on this forum.

Again, thanks for y'alls concern and maybe I can come back with some good news for a change.

 

Saturday September 02, 2006
Friday afternoon, we once again we picked up our Tahoe Friday from the Dealership. They did a complete lifter job on both sides of the motor. They want us to drive it over the long holiday weekend to see if the noise is gone. I took it out this morning and put about 50 miles on it before returning home. I drove it through the drive through at the Post Office and I heard that familiar click, click or tapping noise reflecting off the mail boxes into my open drivers window. The noise didn't return until I pulled into the driveway of my home where my wife was standing. Guess what, the curse of the Tahoe is back BUT not as bad. The tapping noise only lasted for a minute or two then went away. What a week I'm having. I drove it around the neighborhood for awhile and nothing. Three hours later my wife drove it to the Post Office again and she said she could hear it when acceleratiog away from a stop. She called me on her cell and wanted me to stand at the curb in front of our house and listen while she drives past. She did this three times with no noise that I could hear. Sunday is another day and she will take it to Church then after drive it around for awhile. Monday we will do the same but I'm not very optimistic at this point that the repairs did any good. We also have developed a new little problem. The right front window is making a scratching noise when it's rolled up or down. It sounds like metal scratching against glass. They said it was repaired but the noise is still there when compared to the other windows. As for the exit lighting they have parts on order. One last thing we have made a call to GM explaining our problems and expressing our displeasure with this vehicle. We are taking the first steps to get GM to replace this vehicle or return our money. Wish us luck and I hope that nobody else has to go through this kind of trouble with their brand new vehicle.

 

Sunday September 3, 2006
Today we continued our road testing with poor results. Yes, the noise is still there and just as bad as before. Now, there seems to be an antifreeze leak and the odor is very strong. Needless to say, we are very disappointed in this vehicle and General Motors. I have owned nothing but Chevrolets all my life and have never experienced anything like this before. Our anger is focused at GM and not the Dealership. The Dealership has done everything they could along with input from GM Engineers to alleviate the problems with our vehicle. Pulling the heads and doing a complete lifter job on a brand new vehicle with less then 1,000 miles is unacceptable to me, not to mention it didn’t fix the problem.

Therefore, Tuesday morning I will be returning the vehicle to the Dealership and demanding GM either replace it or return our money. It’s a shame it’s come to this because our family is very loyal Chevrolet customers. Everything in our driveway is Chevy, and I have taken great pride in telling our Ford and Chrysler owning friends what fine vehicles they are. I guess I will have to keep my mouth shut from now on.

I do have one new observation about this vehicle. I drive with sunglasses and have noticed it is almost impossible to see the gauge cluster. I can barely see the gauges only after removing my shades. It’s really at its worst in bright sunlight. We have the cashmere interior with a black dash. Now I’m aware that my eyesight is not as good as it used to be, but the black back ground makes the indicators very hard for me to read. Has anybody else noticed this or am I just nit picking? My wife has a hard time reading them too.