Tapping noise from engine 07' Tahoe

I have a 07' Tahoe 3LT flex fuel with about 350 miles on it and have heard a tapping noise for a few days now. It seems to be coming from the engine area. It sounds like lifter noise or a spark plug arcing. We took it to the dealer this morning and they told us it was injector noise and it wouldn't hurt anything to continue to operate it that way. They said that sometimes air gets trapped in the system which causes the noise. I guess I'm old school but it sure sounds like lifter noise to me. Has anyone else experienced this problem? It makes me a little uneasy with a brand new vehicle making a noise like that. Does anyone have any ideas? In town gas mileage is 14.5 to 15.1 keeping it under 60 on the freeways. Everything else is super and we really love this vehicle. One other thing, does anybody know how to turn on the exit lights located on the bottom of each outside mirror? Thanks for your help.

The injectors do make a clicking noise during normal operation but this should not be loud enough to be heard inside the cabin.

A rattle noise that can be heard in the passenger compartment during acceleration or at idle could be the result of the Upper Intake Manifold Cover contacting the HVAC module retaining stud.

The lights under the mirror are controlled within the DIC customization options under "Exit Lighting" and "Approach Lighting" settings, also make sure that the interior lights are not disabled the button is above the small rotary instrument panel light control knob and fog light button just to the left of the steering column.

Thanks for your prompt answer ZX1100F1. The tick tick or clicking noise can't be heard from inside but is very noticeable from the outside. The noise is not constant but kinda comes and goes. My wife drove it to work Monday morning and her coworkers standing outside the building heard the noise when she was parking. She works for Lear Corp. in Arlington, TX the people that make the seats for the new Tahoe. One of these people that heard the noise was the Plant Manager. He brought it to her attention. This problem is distracting from the other wise perfect performance we are getting from this vehicle. I hope our dealer will take a closer look the next time we take it in for service. Again, I appreciate your help in this matter.

I have the same injector noise. It's not too notieceable, but I've owned another Chevy that had the same thing and got used to it. Dealership had no fix for it either (normal condition to them).

Now, what bothers me is at idle (and even during driving most of the time) my '07 Tahoe makes sort of a crackling/gurgling sounds. Now, I first thought it had something to do with the air conditioner running (water draining and making noise or something from the underside), but it makes this noise with or without the AC on. Anybody know what this could be? Any ideas ZX1100F1 of what this is?

Sorry don't mean to hijack your thread Gman.

Hey guys back again. I checked for the clicking noise when my wife came home from work today. I think it's getting worse. I was standing over 20 feet away with the hood closed and it sounded like a spark plug wire was off or a dry lifter. Man, it's making one hell of a racket. I talked to the dealer today and I'm taking it in tomorrow. They said that my Tahoe was the only one so far to come back with this problem. At least they will give me a loaner vehicle while they try to figure this problem out. If it is an injector problem why can't they just replace the one making the noise. All I know is this is unacceptable and they better fix the problem. By the way my wife said the fuel mileage is continuing to improve. It's now at 15.5 in town with about 600 miles on the clock. She has yet to drive it over 60 on the freeway. Life would be good if I could just get this thing to stop making all this noise.

Well, we took our Tahoe in to the dealer this morning and the service manager went for a ride with us. He was able to hear the noise thank goodness and offered to take it back to the shop and let the mechanics take a look. That's all they did was look. They seemed to think it's a lifter noise but because it's the first 07' Tahoe in their shop with this problem they aren't willing to touch it unless they get some direction from GM. So we have to take it back on Monday and the dealer will contact GM to send somebody out to give their professional opinion. Man I hate the idea of them tearing into the engine with only about 650 miles on the clock but what can you do.

We seem to have another problem with the exit lights on the outside mirrors. When we program the DIC they work one time entering and exiting. After that only the entering works. We have programed the DIC at least 10 times now with the same results. For some reason when exiting the vehicle they refuse to come on and yes we have checked the dome light switch for the proper setting.

One other thing, our AC is not cooling very well. Yes, it's been as hot as 106 in Fort Worth lately but my 03' Silverado does just fine in this heat. When they took it in the shop this morning they did the current computer update. I'm not sure if this solved the AC cooling problem or not because we came strait home and parked it. Why didn't GM offer rear AC in the 07' Tahoe? My Astro Van had it and it would freeze you out.

I will keep everybody informed on GM's response and how they plan to resolve our lifter noise problem.

I believe all of the 07s have rear A/C.

Your right 73shark it does have A/C vents above the second and third seating areas. Checking with my wife she said you have a seperate set of controls between the two front seats. Having only drove this vehicle only once I wasn't aware of this. I stand corrected. This news only makes my problem worse. Now I know we're getting very poor cooling if this thing has two A/C units. They have to do something about this because driving without A/C in Texas sucks.

I have the gurgling noise from time to time in my 07 LTZ. I also had it in my 05 3/4 ton Suburban. The dealer told me not to worry about it.

Update on the engine noise.... We took our Tahoe in to the dealer and guess what NO NOISE. They let the thing run for over an hour in their shop. They even drove it around for awhile NO NOISE. They even called me at home and I agreed to come in and take it out on the road. I drove it stop and go even at freeway speed for well over an hour. NOTHING, it's as quiet as a baby sleeping. I don't get it. The service manager said they would keep it and fix the other two problems (A/C & EXIT LIGHTING ON MIRRORS) and check for the noise again later today or tomorrow. I must say this makes me look like an idiot with the dealer and I would feel like one if other people hadn't heard the noise. If they are unable to find the problem I guess we will just drive the dam thing until it blows up. At least that way GM will know what to fix. If anything else happens I will keep y'all posted.

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.

It's just a car, it's not like your wife cheated on you or anything, just have the dealer throw a new motor in her and she'll be good as new, quit your nit-picking life's too short.

Wednesday September 6, 2006
This afternoon, the Service Manager called and wanted us to meet in his office. He told us the Arlington GM Plant Driveline Engineer inspected our vehicle this morning. After listening to the engine noise he was dumb founded and didn’t have an answer. During our meeting this afternoon with Jeff (Service Manager) he discussed several options available to us. The first few were no more then dangling a carrot from a stick. He said because GM could not determine the exact problem with our motor, they want to replace the whole engine unit. He said it could be done at the dealership or they would take the vehicle to the Arlington Plant which ever I preferred. Jeff also told me that GM was now offering a 5 year 100,000 mile drive line warranty on all 07’ Tahoe’s which includes the ones already on the street. Jeff also said GM was prepared to buy back my 2 year extended warranty if I agreed to the motor change. Not only that the Parts Department was offering me a free set of 20” Chevrolet Wheels and any other 07’ Tahoe accessory that I wanted. This is all well and good but we still have other issues that are not repaired yet. I have stood back and let GM experiment with a number of their fixes and none have worked. No, not anymore! I refuse to let GM put a patch on a $40,000 vehicle and hand me a few carrots to make me feel better. We told Jeff all this is unacceptable to us and we would consider nothing less then a buy-back from GM. So guess what, Jeff was saving GM’s best offer for last hoping I would accept the carrots. We don’t want anymore from GM then what we deserve and that’s a reliable vehicle that does what it’s designed to do. Jeff will contact GM in the morning to get the ball rolling on the buy-back and we will sit down in a few days and order our second new Tahoe.

Now for Mr. ZX1100F1, you know, I may just be nit-picking about the issues we are having with our vehicle, but $40,000 is very hard for us to come by. You may be rolling in money and don’t give a damn. We, on the other hand, expect to get what we paid for and in this case GM failed to deliver. We don’t buy vehicles every other year like some people. We drive them for at least 8 years if not more. Another reason why I’m nit-picking is this vehicle will be operated primarily by my wife and I don’t want her sitting broke down on the freeway. I’m not asking GM for anything extra, just a dependable vehicle that operates as advertised.

More to come…

Gman:

You may want to rethink the offers from GM. Last year I was involved in a buyback from GM. From what I was told mine went smoother than normal and it still took over 6 months. What if you do trade the vehicle in for a new one with even more problems than you had on the last one. A few years back I was in a car accident and totalled my 02 Suburban, I fought and fought with my insurance company to total out the truck. I eventually got my way, and bought a new 05 3/4 ton Suburban with the money from my insurance and a little financing. Needless to say within a day of purchasing the new truck I got rear ended and the dealership had to replace the frame on my truck. My brand new $55,000.00 truck never ran right after that. I guess the morale of the story is even though you think you might be getting what you want, your probably not. I know it didn't work out to well for me.

My name’s Dave and if you look really close you'll see the smiley face guy at the top of my previous post.

I understand your situation and you have my sympathy, I would not be pleased if my trucks had a noise either but I certainly think from what you have described that GM (and your dealer) is trying hard to take care of you.

FYI, I can assure that no matter what you were told or who told it to you, there will be no work done to your Tahoe at the Arlington Assembly plant.

Early Saturday Morning September 09, 2006
Dave, all I have to go by is what the Service Manager told us in our meeting. He was instructed by GM to present these options to us and returning the vehicle to the Arlington Plant for a complete engine replacement was one of them. Who knows, but it's a non issue to us now. We were told today (Friday) GM is working on the buy-back and it should take about three weeks for the paperwork to be completed.

As for the smiley face, I'm not sure what it's supposed to represent.

As for the service that I'm getting, I have nothing but praise for all the people at the Dealership that have been trying to help us resolve our issues. They have remained very professional through out this process. GM is another story. I don't think they would have been as cooperative if I didn't own a 07' Tahoe. After all, this is one of GM's cash cows along with the Silverado. Besides our journey has just begun with GM. Only time will tell how they respond. So far so good. I'm not sure what happen in Jasonw75's case but we certainly plan to be in a new vehicle in less then six months.

Dave it would be interesting to know your affiliation with GM. You seem to have all the answers on this forum. You must have connections. Anyway, thanks for your 2-cents in this matter. Maybe I can write something good about our next Tahoe.

More to come...