This very well might be in the wrong section. Feel free to move if deemed neccessary.

Is the Blazers power band all over the place? I have only really started paying attention to my blazers recent driving habits. It's almost like a 5 year old is sitting there flipping the switch for a "power on" "power off" mode. During normal acceleration (under 2000 rpm's) the truck does just fine. BUT when accelerating through the gears in a relatively brisk manner (shifts at about 3500 rpm's) it seems like the blazer keeps its power till 2500 rpm, then loses it till about 3000 rpm and keeps it till about 35-3600, loses it once more till it shifts back down into a lower rev band. Under full throttle there is no noticeable difference. You really have to be paying attention to feel the engine struggle. I just had new plugs, wires, and dist. put on so I'm doubting its a spark issue.

I know my aurora will not enter its power band until 3500 RPM's. Then it's like a slingshot. The 4.3's power band just seems to be all over the place!

Am I imagining things?

 

you know what? i was just wondering the same thing EXCEPT, i have headers on mine (which i love, and gave me a great bottom end boost) but i notice my power band drops around 2,700 and picks back up at 3,500 and holds. but like you said, i notice the slack and then the surge. i dont remember what it was like before the headers but it is noticabe

 

I've noticed this too, but i've only noticed it when my defroster or a/c was on. when its off, it pulls strong until it shifts, you can tell power dies off at the top end but the 4.3 makes all its power down low in the range

 

These motors have virtually no powerband lol. I am not very impressed for this motor being a rather large v6 the kind of torque it produces.

 

I have noticed the same thing, power-----nothing-----power again. But I don't know why it is like this.

 

I'm actually rather impressed with the low end torque of the blazer. It is gutless up top, but I think thats what makes the truck most useful. I have nothing but high end torque in my aurora and its worthless for taking off.

I'm just glad I'm not imagining things. Being the first blazer I ever have owned I wasn't sure if I was having an issue or not.

 

It's not in the middle of a shift (from first to second) when you sense this, is it?

My 94 is kind of a pig out of the hole, then as the motor hits 3500 it takes right off and the motor sounds different almost like a different motor? For some reason, my truck is faster at 1/2 throttle than it is at full throttle???

Good luck and I'll be watching this thread to see what you come up with.

 

Nope, it does it before, and after the shift. Your truck sounds the complete opposite of mine.

I had a fishy suspicion that there was an issue with fuel delivery. A local shop that I frequent hooked fuel pressure gauges to the fuel lines and noticed that fuel pressure DROPS between 2712-3520 RPM's and then picks back up till the end of the rev range.

He suggested a new fuel pressure regulator so 97 dollars later I have a new FPR and the same issue. Only now, the mechanic states, that the fuel pressure remains steady and drops hardly at all. Of course insurance regulations mandate that I can not witness the test of said fuel pressure.

Soo all in all I paid 97 dollars for nothing. I am almost sure that this is just the way the engine is.

 

HUH??? Your insurance company states you cannot watch your vehicle being worked on?

Man, that's messed up! ...Dumb question though, what does the insurance company have to do with your truck being worked on? (Not being a smarty, just asking)

"Fuel pressure DROPS between 2712-3520 RPM's" I would be curious of how they measured "2712" and not just 2700 or 2750? Can you take it to another garage? I mean it sounds like this guy (mechanic) is full of something, but it doesn't sound like it's knowledge!

 

In Illinois, or atleast springfield, a customer is not allowed in the shop due to the shops insurance company.

And oh yes, I am pretty sure I got completely ripped off. This is a tech I have never dealt with. I usually have one guy who does work on my cars. Apparently he had the day off.