1999 Suburban Questions/problems...

99k2500burb · May 21, 2007

Hello all,

I am new to this forum and was hoping for some help with some issues that I have been having with my Suburban. I just got this Suburban a couple months ago after a long search. I have wanted a Suburban for a long time since we now have a baby on the way and two large dogs we needed more room and after putting 300K on my Chevy pickup I figured it was time for a new vehicle! I have a 1999 Chevrolet K2500 Suburban, 7.4L V8.

The first problem that I have is when I unlock my doors using the keyless entry, get in the vehicle, put the key in the ignition and turn it to on, then all the power in the vehicle shuts off (dash lights, dome light, radio, buzzer, ect.) I then try to start it and of course it doesn't start. I then turn the key to the off position and can here a constant clicking from under the dash (sounds like a relay) this noise will not stop until I turn the key on again, now the vehicle powers up and I can get it to start. I noticed that the clock on the radio has reset, but other than that, everything else is normal. I put the vehicle in reverse, back out of the drive and about the time I turn the wheel and hit the brakes the electircal system powers off again and the engine almost stalls. The entire system them powers up again (I can't remember if I took my foot off the brake or not) and then I don't have any more problems driving until the vehicle sits for a couple hours then it does the whole thing again the next time I start it. I'm hope someone has had this same problem before! I'm clueless!

The second (and even more annoying, if that is possible!) problem I am having is after driving at 40+mph for about a minute or so, I start to hear a "swooshing" or "rotating" noise coming from under the dash board. The noise seems to change speed with the vehicle speed, but can not be heard under 40mph. The really wierd part about this noise is that is can be heard when going straight down the road, or on a slight left turn, but goes away when the steering wheel is turned slightly to the right or when speeding up. It almost sounds like a speedometer cable or something rubbing, but I'm pretty sure this vehicle doesn't have a cable running up to the dash and I have no idea why the steering would effect it.

I don't know if anyone has heard of this problems before or not.....or if there is even a slight possiblity these two problems are related, but I would appricaite any help on either issue!

Thank you very much in advance!

Bill

ryank1 · May 21, 2007

The first problem could be the ignition switch itself shorting out, for the second problem look for a tear in the boot at the base of the steering column.

1999 Tahoe 4x4 · May 23, 2007

As far as your first problem

+1 Vote for Ignition Switch, that is the electrical switch component of it.

I had to replace mine aready. If I remember correctly it is around $300.- at the dealer.

Don't start without having an deep E4 Torx. (E4 NOT T4). E5 Torx is necessary as well.

99k2500burb · May 24, 2007

Thank you very much for the replys!

After reading what you both said about the ignition switch, it totally make sense! Is this a real pain to replace? The last one I did was on my '94 Chev K1500 and I'm guessing since the entire steeling column is different (including the addition of air bags) the replacment process might be different also! Is the swtich in the steering column or is it up in the dash?

As far as my second issue goes....

I tore most of the dashboard apart thinking that something had to be rubbing on something and couldn't find anything out of place. I checked all of the boots on the axles and the steering shaft and everything was fine. It sounds like it is seriously coming from inside the vehicle, but now I'm begining to wonder. If there anything in the engine compartment or on the firewall that could cause this noise? I remember reading somewhere (can't remember where) about a leaking exhaust donut causing a similar noise, but for the life of me, I can't find the information now that I need it again! I wish I had a better way of describing this noise, but like I said before, it is like a "wooshing" or "rubbing" noise that seems to be related to something that is rotating. I know this probably sounds really funny, but I can't think how else to describe it!

Thanks again for the help, I really appriciate it!

Bill

1999 Tahoe 4x4 · May 24, 2007

As far as first issue:

To change the switch can take anywhere between an hour and the whole comfortable afternoon. You will definitely need the deep E4 and E5 Torx. (Snap-On STLE40 & STLE50)

The ignition switch has two components. The mechanical and the electrical component. You will need the electrical component (GM part #26075995)

Start with removing the instrument basel cover, I mean the unit that has the driver A/C vents. It should just pop out. At this point I would recommend covering the instrument cluster with some masking tape or some other sort of protection. I came several times close to scratching mine.

I can't describe the whole process, you will have to figure things out as you go. I just want to point out some steps that are tricky and that took me a while to figure out.

1. The top half of the steering cover comes off best when you tilt the steering all the way down.

2. In order to take the bottom half of the steering cover off you have to yank out the height adjustment knob. It might be tight but don't worry. Just yank it out, it comes out. You will need the E5 Torx for the top steering cover and a regular (T-Type) torx screwdriver for the bottom cover.

3. When you can see the electrical component of the switch exposed you might have problems to disconnect a little white single-wire connector. Be careful; this is your pass lock connector. You will have to turn it/rotate it out. Just try, it will work. Remember how you did that, as it might be tricky to put it back.

4. BTW: don't worry about the pass lock system too much. You don't have to reset or recalibrate or re-re-re-do anything. The ignition switch electrical component is all OK/ready to be changed as long as you don't change the lock/key.

5. You have to disconnect the switch from the main harness. This is going to be an uncomfortable deep under the steeringwheel job. You will need a (I think deep) 10mm socket. Unscrew the nut and slide out both sides of the switch connector. This was quite tricky on mine it really looked like it is not going to work. But at the end it did. Remember the correct sides, although you can't mix them up. It only goes back in one way.

That is all that I can think of know as far as your first issue. If you need more help let me know. I'll be unavailable for a few days next week, just so you know.

As far as you second issue. You really need to be more specific. Is it speed sensitive? RPM Sensitive? What about turning left or right?

Just a wild wild guess. If yours is a 4x it could be that the 4x4 is constantly engaged. Mine makes quite some noise in 4x mode.

99k2500burb · May 25, 2007

Thank you again for the help and the detailed information, it will help very much during my vehicle project this Memorial Day weekend!

The second problem is still troubling me. The best way to describe it is a noise that seems to change speed with the vehicle speed (not for sure engine speed, when I speed up the new gets faster and louder, but doesn't occur at high RPM's at low speeds), but can not be heard under 40mph. The noise can be heard when going straight down the road, or on a slight left turn, but goes away when the steering wheel is turned slightly to the right or when speeding up. It almost sounds like a speedometer cable or something rubbing, but I know this vehicle doesn't have a cable running up to the dash and I have no idea why the steering would effect it. The noise sounds like it is coming from inside the vehicle, but now I wonder if there is anything in the engine compartment or on the firewall that could be the cause? Mine is a 4x4 and I know the axle isn't engaged (doesn't hop when making a tight turn, either direction) and the switch is in the 2WD setting. After reading the last reply, I drove it in 4x4 for a little bit and could feel (and hear) the axle kick in and out just fine and that isn't the same noise I was hearing on the highway. I guess I don't know if the transfer case could possibly stay locked in 4x4 or not?

Thanks again for the great help, I really do appriciate it!

Bill

MustGoFaster · May 25, 2007

well -this may not exactly be it, but I had a bunch of trouble with my jeep that was similar to your #2 problem. I had a bad wheel bearing and the front driveshaft (transfer case propeller shaft) had dry joints.

another thing you ccould consider is that perhaps the steering shaft grommet or similar material is loose/worn/missing

Jackie · June 8, 2007

I had similar problem #1. There was nothing else I could do but replace the thing. It was the time when I was accessorizing my truck. So I had to take for granted my present plan of buying a Chevrolet Pickup Tail Light Cover for the replacement. I got it all budgeted so I needed to make a choice which to take first. Good enough that I got it all settled the following day.

GRB60 · June 8, 2007

I had similar problem #1. There was nothing else I could do but replace the thing. It was the time when I was accessorizing my truck. So I had to take for granted my present plan of buying a Chevrolet Pickup Tail Light Cover for the replacement. I got it all budgeted so I needed to make a choice which to take first. Good enough that I got it all settled the following day.

Huh?

Jackie · June 9, 2007

Huh?

Why?

99k2500burb · July 18, 2007

Hello all,

I just wanted to give everyone an update on the issues I was having with my 'burban:

Issue #1 - I was just getting ready to start replacing the ignition switch, went to the battery and realized whoever last installed the positive battery cable managed to get about 3/4's of the rubber groumet caught between the cable and the actual battery. This was preventing full contact and created a bunch of acid build up between the surfaces....cleaning up the build up and trimming away the damaged rubber groumet fixed the problem! I should of checked the battery to begin with! (mental note to self: K.I.S.S. - Keep It Simple Stupid!)

Issue #2 - Turns out this wierd "swooshing" noise was my power steering pump! The pump started making awful noises whenever I started turning, so I replaced it (stuck relief valve) and it took care of the noise on the highway....I guess it was the noise that lets you know the pump is about to crap out!

I just wanted to say thank you to everyone that offered suggestions on my automotive issues and I apologize for taking so long to respond back with the solutions....after all that is how everyone learns...from other's expiriences!

Bill

etex211 · July 18, 2007

Regarding that battery cable.......

I believe that your Suburban has the same dual battery cable setup that my '96 Crew Cab truck has. I had all kinds of problems with those cables. What happens is that, over time, the rubber around that cable end swells, preventing the cable from being tightened fully against the battery terminal. You can tighten the cable, and then a few weeks or a few months later, it will be lose again. I fought this problem on my truck for two years, until finally, I lost all power, including lights, when I was coming home one night on a dark road. It scared me to death.

I got the solution from a friend of mine, who had experienced the same thing with his wife's '99 Tahoe. Strip the rubber from around the cable end, which leaves a wide flat surface to tighten against the battery. Then, use a 3/8"x2" bolt with a jam nut to tighten the cables against the battery terminal. This solution isn't pretty, but it is very effective.

Hope this helps.

99k2500burb · September 27, 2007

Hello all,

I hate to bring this post back from the dead, but my steering related noise came back (never really totally went away) after I replaced the power steering pump.

So, I was hoping that if I did a little better job describing this "noise" I'm having, maybe someone has heard of it before and can shead a little light on the subject! I have been dealing with this noise for about three months now (not for the full three months, we had a baby girl in July!) and I am almost to the point where it is going to a shop!

I have a 1999 Chevrolet K2500 Suburban, 7.4L V8, 174K Miles, VIN: 3GNGK26J2XG138043. The Suburban has the Hydroboost braking system (and a brand spanking new power steering pump)!

The noise is a "swooshing" noise (it sounds like an old speedometer cable that needs oil) that you can hear from inside the vehicle. This noise is NOT heard at idle in Park, once you put the vehicle in reverse (with the brakes on) the noise softly starts up, and then will go away if you turn the wheel a little bit in either direction, but come back again when the wheel is centered. Once you put the vehicle in drive the noise starts up after you hit about 10 MPH and gets louder with the higher engine RPM's (not the vehicle speed, although at highway speed the noise is unbearable!). The really weird part is that the noise only occurs when you are going straight or turning left, it completly goes away when you turn right. Upon further investigation (I removed 75% of the dash board and instrument panel) the noise sounds like it is coming right above the pedals. I checked every possible componet under the dash (friend driving, me diagnosing) and couldn't find anything that was making the noise, but it was coming from that area. I assumed that since the noise went away when I turned right that is was probably related to the power steering (plus the pump was being a little noisy) so I replaced the power steering pump only to have the noise come back!

The only last thing that I can think of is that if there is some kind of relief valve or something in the Hydroboost brake booster (attached to the firewall) that is chattering or sticking and that is the creating the noise problem (so kinda related to the power steering pump?)...which would explain why I can here the noise inside the vehicle by the pedals?!

I really appriciate any help/advise that anyone has regarding this issue, I am really at my wits end with this noise and don't want to bring it to a shop (don't have a lot around here that I trust anymore!)

Thanks, Bill

99k2500burb · June 6, 2008

Hello everyone!

Once again I am bringing this post back from the dead. I haven't had as much time to work on the 'burban due to my little (almost 1 now) girl being born! As it stands I am still having issues figuring out this noise on my truck...

I will refresh my issue, first, I have a 1999 Chevrolet K2500 Suburban, 7.4L V8, 178K Miles, VIN: 3GNGK26J2XG138043.

So far I have replaced the power steering pump, Hydroboost brake booster, and bled and flushed the entire power steering system.

The noise ....I would describe it as a swooshing noise. Almost liquidy? Like an old speedo cable that needs oil. It occurs mainly when driving on the highway, over 2000rpms, it doesn't happen (or I can't hear it) when accelerating, but once you are at the cruising speed, it starts. It only occurs when the steering wheel is straight or left, it goes away when you turn right (which is why I originally thought it was a power steering/Hydroboost issue). If you are cruising and you need to accelerate hard, it goes away until you are off the gas. When you first start the truck and put it in reverse with your foot on the brake you can faintly hear it. The noise is heard from what sounds like the firewall area in front of the driver's seat. If you are on the highway and put the truck in neutral it goes away until you rev it back up over 2000rpms.

Today while trying to replicate the noise in the garage, I had the truck in drive with my foot on the brake and hit the gas and heard an interesting clunking noise, which might be the mysterious swooshing noise. After doing some digging, I came to the conclusion that my driver's side motor mount is having some issues. The motor leaps about 2 inches and from the right angle you can see the motor mount clanking together. When this same situation is done with the truck in reverse the motor doesn't hop at all, which leads me to believe that the passenger side mount is probably ok.

I guess my question is, could the bad motor mount be causing a noise that is affected by the steering of the vehicle or is this just another part that needs to be fixed that won't get rid of this terrible noise? I remember someone saying that an exhaust donut might make this noise? Could a combination of the motor mount being bad weaken the exhaust donut enough so this could happen? I don't hear any exhaust type noises however....I guess thinking back to physics, if you were turning the weight of the motor would shift and put more load on the bad motor mount (right turn equals left engine tilt?)? What kind of project is replacing one of these motor mounts, it didn’t seem like a ton of room to get to it?

I love this truck and it is such a huge part of our family and I really want to get it back so it can be driven on the highway without the windows down or the radio at full blast! I really do appreciate any help on this issue. I figured I would give it one more go on my own and then it might just have to go to the dealer, but I don't want them to tell me about and fix things that I know about (noisy lifter, leaking oil cooler lines) or don't want to fix in an attempt at fixing this problem! I guess I just like the satisfaction of doing things myself....

Thanks again everyone!

Bill