DeNReN 0 #26 February 26, 2008 As some have said it could be a mulitude of things.. 1st thing I would check is fuel pressure and volume...those 4.3l's with those damn "spider" injectors need atleast 60psi....58 psi will cause problems similar to what your describing. <----Class A Interprovincial Journeyman Automotive Tech....ASE Master Tech....ASE Advanced Engine Performance Specialist..etc..etc...etc. Quote Share this post Link to post Share on other sites
jsaxton 0 #27 February 26, 2008 Could be the Mass Air Flow Sensor also. This guy should spend the $0 and go get the OBDII codes read at AAMCO Quote Share this post Link to post Share on other sites
DeNReN 0 #28 February 26, 2008 Could be a loose nut behind the wheel too...those are super dangerous.. No check engine light......no codes. Quote Share this post Link to post Share on other sites
skydemon2 0 #29 February 26, 2008 I'd check the blinker fluid...... And maybe the cat. Beauty is only skin deep, but ugly goes clean to the bone! I like to start my day off with a little Ray of Soulshine™!! Quote Share this post Link to post Share on other sites
cloudseeker2001 0 #30 February 26, 2008 Quote Quote My 2001 Chevy Blazer started acting funny a few days ago. I want to challenge you "Click & Clack" people out there to diagnose what could be wrong with my vehicle. (Click & Clack are the nicknames for the two guys that do a call-in radio show diagnosing automobile problems.) The problem: When accelerating from a stop, the engine stalls out. It can be immediately re-started, but may cut out several more times before acceleration is achieved. Being very light on the gas pedal helps - so light that you almost aren't accelerating at all (and that's really difficult for me). When on cruise control and hit a hill, the engine cuts out repeatedly for about a second at a time as it attempts to climb the grade. And these engine stalls only happen when the gas tank is less than half-full. It runs fine on the first half of the tank. That little tidbit really sweetens the mystery. So, do any of you professional or backyard mechanics have an idea what could be going on here? My thoughts: 1) A bad tank of gas? This started happening after a top-off at a very remote national park (Big Bend, Texas), which doesn't have much gas turnover at the camp store. However, several tank re-fills since have failed to clear the problem. 2) There is also a lot of fine powdery sand through which I was driving on dirt roads. The air filter was not clogged. Could it have gotten into the gas tank? I welcome informed thoughts. Attached: Photo of "Big Red" next to the stone ruins of an old ranch home in the Texas desert. I would check for a corroded rotor in the distributor. You may also need a new distributor cap. I would check for both, if i were you. Yves. Most likely does not have a rotor or distributor. "Some call it heavenly in it's brilliance, others mean and rueful of the western dream" Quote Share this post Link to post Share on other sites
DeNReN 0 #31 February 26, 2008 Quote Most likely does not have a rotor or distributor. Yes it does...and its whats reffered to as a crossfire cap...and they are a very common problem...as are coils,plugs,wires,MAF sensors...etc..etc...etc..etc... Quote Share this post Link to post Share on other sites
cloudseeker2001 0 #32 February 26, 2008 Something to do with the fuel filter, fuel pump, fuel pump screen, fuel system pressure problem to include bad fuel cap. "Some call it heavenly in it's brilliance, others mean and rueful of the western dream" Quote Share this post Link to post Share on other sites
CSpenceFLY 1 #33 February 26, 2008 Could also be a leak in the fuel pickup, depending on where the pump is.Or as mentioned above,many ignition problems. Quote Share this post Link to post Share on other sites
Armour666 0 #34 February 26, 2008 sounds more like a bad Mass Air Flow Sensor it will cause a lot of the same symptoms your discribingSO this one time at band camp..... "Of all the things I've lost I miss my mind the most." Quote Share this post Link to post Share on other sites
bloody_trauma 2 #35 February 26, 2008 sounds to me like baglock... yep thats definitely your problem, go ahead and release your main and deploy your reserve... Fly it like you stole it Quote Share this post Link to post Share on other sites
AggieDave 6 #36 February 26, 2008 John, Check your fuel filter and the fuel pump. Although you're going to HATE replacing the fuel pump. You get to drop the gas tank. I did that on my old truck last year, its a complete pain in the ass.--"When I die, may I be surrounded by scattered chrome and burning gasoline." Quote Share this post Link to post Share on other sites
Andy9o8 1 #37 February 26, 2008 QuoteYou could have a clogged fuel filter or fuel supply line that may be robbing the engine of fuel. [And/or] if your vehicle has a fuel pump go out then you may not get enough fuel during accelleration. That's my vote, too. One way or another, when the throttle opens up, the engine is starving for fuel. Quote Share this post Link to post Share on other sites
Andy9o8 1 #38 February 26, 2008 QuoteJohn, Check your fuel filter and the fuel pump. Although you're going to HATE replacing the fuel pump. You get to drop the gas tank. I did that on my old truck last year, its a complete pain in the ass. I found it quite easy. Drive it into the mechanic; pick it up at the end of the day. Quote Share this post Link to post Share on other sites
DJL 235 #39 February 26, 2008 QuoteChevy Well, there's your problem."I encourage all awesome dangerous behavior." - Jeffro Fincher Quote Share this post Link to post Share on other sites
AggieDave 6 #40 February 26, 2008 Sure you had it easy, but I only spent $30 to put a new fuel filter in my old truck. Had a friend that was the manager at a parts store and I did all the work myself. It took about 6-hours of work. I bet you paid $300 to get it done for you, right?--"When I die, may I be surrounded by scattered chrome and burning gasoline." Quote Share this post Link to post Share on other sites
kschilk 0 #41 February 26, 2008 It may sound odd but I suspect the problem may be in the sending unit, for the fuel gauge. This is rare...especially on a GM but I've seen it happen. Check all the grounds and connectors. Another possibility (as previously mentioned), is the fuel pump itself. Gasoline cools the pump and as the fuel level drops, the pump (if worn) may weaken and won't maintain spec output. Generally, fuel pumps tend to s**t the bed altogether...you don't usually get a "warning by weakening" but it does happen."T'was ever thus." Quote Share this post Link to post Share on other sites
CSpenceFLY 1 #42 February 26, 2008 How would the fuel gauge sending unit cause this problem? Quote Share this post Link to post Share on other sites
jasonRose 0 #43 February 26, 2008 Diagnoses = Grim Cause: You bought a Chevy Blazer.... Some day I will have the best staff in the world!!! Quote Share this post Link to post Share on other sites
diablopilot 2 #44 February 26, 2008 Quote I'm gonna go with fuel tank pressurization. Bingo. So a check might be running it with a 1/2 tank and the gas cap off for a bit. If that's the problem, then a new gas cap is about 8 bucks.---------------------------------------------- You're not as good as you think you are. Seriously. Quote Share this post Link to post Share on other sites
kschilk 0 #45 February 26, 2008 In essence, it could be robbing ground. It sounds silly, I know....but nowadays, everything is bassackwards. Switches, relays, etc. go to ground, most everything is "hot" at all times. A ground can be robbed by a "bleeding" connection with another component or a shared ground....it's basically the same as robbing power. I've actually only seen the gauge itself, cause this problem once...it's usually in the harness."T'was ever thus." Quote Share this post Link to post Share on other sites
jm951 0 #46 February 26, 2008 I'd go with fuel pressure from whatever cause. A new fuel cap is cheap, try that first. Past that, find a wrench you trust who has a gauge to check fuel pressure. Next up, with 100k miles, time to change the muffle fluid and turn signal grease. Quote Share this post Link to post Share on other sites
bloody_trauma 2 #47 February 26, 2008 trade that chevy in for a pinto my man Fly it like you stole it Quote Share this post Link to post Share on other sites
JSBIRD 1 #48 February 26, 2008 QuoteMy 2001 Chevy Blazer started acting funny a few days ago. I want to challenge you "Click & Clack" people out there to diagnose what could be wrong with my vehicle. (Click & Clack are the nicknames for the two guys that do a call-in radio show diagnosing automobile problems.) The problem: When accelerating from a stop, the engine stalls out. It can be immediately re-started, but may cut out several more times before acceleration is achieved. Being very light on the gas pedal helps - so light that you almost aren't accelerating at all (and that's really difficult for me). When on cruise control and hit a hill, the engine cuts out repeatedly for about a second at a time as it attempts to climb the grade. And these engine stalls only happen when the gas tank is less than half-full. It runs fine on the first half of the tank. That little tidbit really sweetens the mystery. So, do any of you professional or backyard mechanics have an idea what could be going on here? My thoughts: 1) A bad tank of gas? This started happening after a top-off at a very remote national park (Big Bend, Texas), which doesn't have much gas turnover at the camp store. However, several tank re-fills since have failed to clear the problem. 2) There is also a lot of fine powdery sand through which I was driving on dirt roads. The air filter was not clogged. Could it have gotten into the gas tank? I welcome informed thoughts. Attached: Photo of "Big Red" next to the stone ruins of an old ranch home in the Texas desert. JR, Been there, done that, with a very similar Blazer. For some reason during the winter, this particular model produces a lot of condensation in the tank, anytime the fuel tank is not kept full. This factor, combined with the bad fuel you already got, has you running very rough. All you gotta do is get rid of the water in your tank. Go to Pep Boys or a Chevron Fuel Station and get twice as much Techron as is called for on the bottle. Fill your tank at trusted fuel station, and drive at least 25 miles. End of problem. Thank me later. BASE359"Now I've settled down, in a quiet little town, and forgot about everything" Quote Share this post Link to post Share on other sites
kschilk 0 #49 February 26, 2008 Quote Next up, with 100k miles, time to change the muffle fluid and turn signal grease. Don't forget to replace the starter bumpers and if you disconnect any wires, be sure to bleed-out the air."T'was ever thus." Quote Share this post Link to post Share on other sites
jenfly00 0 #50 February 26, 2008 Gun oil in the fuel line. ----------------------- "O brave new world that has such people in it". Quote Share this post Link to post Share on other sites