Vapor Lock?

[Lips]

I have a 05 H2 SUT with 50K miles that has recently started to ?surge? when I travel at a consistent speed under 60 MPH. It seems to only affect it when the temperature outside exceeds 85 degrees. Has anyone else had this type of problem?

[Marauder]

Originally Posted by Lips

I have a 05 H2 SUT with 50K miles that has recently started to ?surge? when I travel at a consistent speed under 60 MPH. It seems to only affect it when the temperature outside exceeds 85 degrees. Has anyone else had this type of problem?

Vapor lock doesn't happen on fuel injected cars. But they have their own problems.

Have you cleaned your mass air recently/ever? I would clean it if you haven't. Also check all the spark plug connections. At the plug and coil. If you are handy I would check the plug gap and condition as well.

[Tex_h2]

I had the same problem.....around 55mph.....Changed the MAF....."knock on wood" hasn't happen since....runs alot better...

[Lips]

Thank you Marauder. As far as me being handy my brother?s did not want their sister to be a complete idiot with car mechanics but I think I will have to go to one of them for the plug gap. I appreciate your help and will try this ASAP.

[Lips]

TexH2...did you try to clearn your MAF prior to replacing it?

[Tex_h2]

No, I was going to clean it, but then I got a decent deal on a New MAF to go with my CAI.......and like I said, since the change out I haven't noticed the problem...so I would try cleaning it first. I also notice that my stock MAF had a few tiny holes in the metal screen....

[Marauder]

Lips,

Plugs are hard to get to but you can do it. I am 6'6" and even I had to stand on a 2 step kitchen 'step stool' to get all of the plugs except the rear passenger side. That one I had to get from inside the wheel well by hugging the tire and reaching up under the inner fender well cover. Make sure your truck is absolutely cold when you do it. Never try to pull the plugs when there is even a little heat left in your engine. The gap should be set at .040. But confirm that in the manual for your year truck.


Regarding cleaning the maf, I just did it myself as well. I just purchased my truck a few weeks ago. So not knowing what had been done before I got it, I purchased a can of the MAF cleaner from my local auto parts store. Was maybe $5 or $6. Took a little maneuvering to get the MAF out but once you do, just spray it clean inside and out. Just make absolutely sure you dont physically hit the little wires inside or you WILL be buying a new one. You spray them but dont touch them with the plastic tube on the can.


By the way, no offense intended (didnt sound like you took it that way but just in case) on the mechanical comment. You just never know how much people are willing to do on their own unless you know them personally.

[Lips]

Marauder, Absolutely no offense taken! I think I know my limits on this and I will let you know what my brothers are able to do.

[HUMMERcustoms.com/TAZ]

If you want to take just a little more time in the plug change you can take out the inner wheel well liner. Tire removed and you will be staring right at the plugs.

The inner liner is very easy to R&R and it makes many repairs easier but, just a little more time.

TAZ