Hey guys, Im new here, but this place is great...a wealth of knowledge to be found here.

So heres my issue... My 2000 Blazer (4.3, automatic) normally gets about 300 to 340 miles to a tank. I noticed this winter that my truck was progessively getting less and less between fills. I normally drive highway but lately I have been mostly inner city travel. I at first just passed it as being the typical city mileage of the truck. Well, been back on the highway now for about 3 weeks and noticed that the truck seems to strugle to get up to speed. And I have to really get on the pedal to get to 70mph and hold it. If I hit a hill, I have to floor it and drop a gear to maintain speed. Also, at about 60-65mph, if I try to feather the pedal to hold that speed, the truck sputters a bit then comes out of it and goes. Problem is far less noticeable with cruise engaged. I was planning on doing a fuel filter change, its due anyway and sending it for a fuel system cleaning, truck has just over 100,000 miles on it now.

Just looking for opinions here before I start throwing money at the problem with no real direction. My fuel gauge stopped working about 3 years ago... typical of blazers from what I hear, but has never raised an issue with power. I was wondering if possibly the pump itself is now going bad. Or am I possibly looking at an ignition problem? TPS maybe? Thanks for any help folks.

 

[sm=welcomesign.gif]to the Forum.
Okay, here goes a long post. I can think of three things right off the bat to check.
1.Change the fuel filter if you haven't already.
2.Get underneath and rap on the catalytic converter to see if it rattles. If it does, it's gone. A plugged up cat will cause loss of power at highway speed if you try to accelerate.
3. Test the fuel pump (I swear I'm gonna post this in the DIY section some day ). Connect a fuel pressure gauge to the inlet line schraeder valve at the top rear of the engine. Turn the key to the 'on' position and see if the pressure reads ~55-62psi. Turn the key off and see if the pressure drops more than ~2-3psi right away. Watch the gauge for several minutes (you can walk away, it's okay) and see if there is any further drop in the reading.
4. Have you done a basic tune-up (spark plugs, wires, distributor cap and rotor)?
Get back with us and tell us what you've found out.

 

That's what I get for not hitting the submit button when I had this typed up 20 minutes ago! LMAO

The first few things that I'll recommend are just preventative maintenance. I do think that it would be a good idea to replace the fuel filter.

It is also possible that you are getting some water or condensation in your fuel, a bottle of ISO Heat (red bottle) should improve things if this is the case - its pretty cheap.

The next thing that I would do if you suspect fuel system problems, I would run through a few bottles of Chevron Techron Concentrate Plus (the one that treats 20 gallons). Use one bottle in the next 3 tanks.

Clean your EGR valve by removing it and thoroughly cleaning the inside of the valve with some sensor safe carbon cleaner. Get a new gasket with the internal screen.

Clean your MAF sensor with sensor safe cleaner. First remove it from the intake duct work. Remove the inlet/outlet transitions by removing the 4 socket headed cap screws. Carefully clean the elements, first trying to clean them with the stream from the bottle of cleaner. If that doesn't work, then you may have to use a q-tip soaked in the cleaning solution, but again, be VERY careful. Break an element and the sensor is shot.

Check the plugs for fouling. Check the wires for arcing (mist clean water over the wires with the engine running in a dark place). Check the cap and rotor for wear and/or carbon trails/build-up inside the cap. Replace as necessary.

 

Thanks fellas.. Im going to do the fuel filter on Saturday, if the weather holds out... and actually the cat slipped my mind, im gonna check that too while im under the truck. I will also test the fuel pressure. I'll probably make a post Sat afternoon. Thanks again! God I hope its only the 40 dollar filter

 

the filter is more like $10 not $40 just so u know

 

I discovered a few things today. One the oil filter for our 97 Blazer is the same one I use on our 93 Chevy Lumina. Also the Fuel Filters are the same. When did Chevrolet get so standard?
I would do a tune up, Wires for sure. I bought ours with 87,000 miles & it needed wires right off. Bad enough to throw a PO305 code. Plugs looked great.

 

Long before my time. GM has done it for a very long time, and with just about everything on the vehicles.

This one might fry your noddle.
The tranny behind your 4.3L V6 is the same one behind the fullsize light duty trucks with V8 engines. There are a couple of minor internal differences, but on the outside they are the exact same things and can be swaped. In other words all the 1/2 ton pickups, all the 1/2 ton fullsize SUV,s the fullsize 1/2 ton vans and your S10 all use the same tranny. Lets take it one step further, the clutch packs inside the 700R4/4L60/4L60E tranny are the same for both the 90 degree engines (4.3L & small block V8) and the 60 degree V6 engines. I took the clutch packs from my '00 S10-Blazers 4L60E behind a 4.3L V6 and put them in my '87 S10-Blazer with a 700R4 and a 2.8L V6 engine. They had a 100,000 miles on them when I swapped them to the '87 and that was 2 years ago. Last report from the turcks current owner, and I quote. This thing is a beast.

Did you know you can swap the sbc V8 engines without too much difficulty? This means you can take out the 4.8 and put ina 5.3, or take out the 5.3 and put in a 5.7 or a 6.0 without much trouble.

Axles are pretty interchangeable in the fullsize trucks too.

GM has been doing it for a very long time. Interchangeability of parts is one of the reasons GM are so popular. The other is the strength and power of the GM engines and trannies.

The 700R4/4L60/4L60E is the best auto tranny on the market. Not only is it in the trucks, GM stuffed it in the Corevette, and a few other vehicles. Firebirds, Camaros, Astro vans, just about everything with rear wheel drive and a SBC engine 1/2 ton and under, including some 3/4 ton vehicles too. Hows that for versitility.