A while back ago I posted about a cold start problem I was having, which included SES lights etc.

I did all the basics, plugs/wires, fuel system cleaning etc and that did not help. In fact, things had progressively gotten worse over the weeks so I finally made an appt. to bring it in to the dealer where I bought the truck.

Their final analysis was that the intake manifold is very badly warped, causing the problems in the morning. Has anyone ever heard of this happening on the 5.3L engine...it's an '00 Silverado by the way.

To top that off, I also had them look into my harsh shifting at low speed, sloppy shifting at WOT tranny problems, and it turns out to be an elongated hole in the valve body plate.

The truck is no longer under warranty (sits with about 60K on it). These problems started popping up between 50-55K miles....way too early for any of those things to be happening if you ask me. In fact, I feel those things are manufacturing defects and shouldn't happen at all.

Anyway, I'm just looking to see if anyone has heard or had any experience with either of these problems and how a dealership (or Chevrolet) may handle them with an out-of-warranty vehicle?

Suffice it to say, this is the 2nd GM truck that I have owned that has proven to be junk way before it's time and it is very likely that once fixed I will be trading this thing in for something not made by GM.

 

Wow, I'm sorry to hear about that. My 2000 Blazer suffered from a lot of quality problems, but my '02 and this '04 have been near flawless.

I've never heard of either of those problems happening. I think the intake warp could have a part in the odd shifting you're having.

 

PM blownchevy ans see if he has any more stock intakes for sale. He was selling them for about $100 I think. Much cheaper than you will get at the dealer.

 

Never heard of an LS1 style intake warping, especially since they are made from a composite type of material. The material should theoretically not be able to warp. Sounds like a defective part to me.
The Silvo has held up well but my wife's 03 Trailblazer has been down for 3 separate long-term repair issues ( airbag, fuel tank, trans slippage ). Kinda rubbing me the wrong way at times. Hell tho, my Dodge has the major brake woes that cost me $400 for decent front brake rotors ( under 24K miles ).
**** happens no matter what the fender/grill emblem says.

 

My factory intake on my 6.0 was warped.....not enough to cause real problems but it played hell with my trims when trying to tune it, luckily the problem was at a place that we could silicone it to seal the leak...after the LS1 intake swap I've had no problems

 

Yelo, my FT's have always been out of wack... they're pretty consistantly 1-2, maybe 3 "points" different than each other. Was yours like this?

I found it odd this week, when I went to install headers - the entire passener side of the truck's manifold bolts were a little corroded and harder to get out. When I had to go back in two days later to redo manifold gaskets, the same thing - they new bolts on that side were harder to get back out. That kind of puts the thought into my head that that bank was running hotter than the other.

 

i worked at a chevrolet dealership, and a customer broght in a 2001 or so K Tahoe. it had a very weird missfire at certain RPM and throttle ranges, and would set a P300 code at times, and the history data would show misfires on all the odd numbered cylinders.

i thoguht about it for a while and tried the old trick, spraying carb cleaner at the intake and litsen for the engine to stumble.

watching the Tech 2 i saw misfires pop up when i sprayed on the drivers side, some ports more then others, but deffinatly an intake leak.

well as it turns out the intake was warped on the 5.3. GM specifications in Service Information says a warpage of 0.122 is acceptable as a maximum when measured over a 8 inches, or two intake ports.

i also noticed the intake gasket was rolled over and looked like it could have been the problem.

the customer was rich and didnt want to chance more problems and bought a new intake.

I think just a new set of intake gaskets could solve the problem.

 

ZBass28, what part of Illinois are you from? Asking cause I have an intake sitting here collectin dust that I'll let go cheap. Let me know if you're interested, thanks.

 

I have seen this problem where I work concerning your cold start missfire. Havent come across any warped intakes though, just rolled intake gaskets. You are at the miles that we see this the most. I would change intake gaskets, you will most likley be fine after that.

 

A buddie of mine works at a Chevy dealer and they have had some warped truck intakes roll through there.

Bruce