punch the accelerator, engine bogs down?

This sounds like the MAF sensor needs to be replaced. Here are two guides to help us fix the problem.

https://www.2carpros.com/articles/how-to-replace-a-mass-air-flow-sensor-maf

and

https://www.2carpros.com/articles/engine-hesitates

Please run down these guides and report back

Thanks for this post, I replaced the MAF sensor for $78.00 and the problem is gone! I love this site.

I have a 96 Chevy S-10 Blazer with 163000 miles. I am having a problem with the engine stumbling and getting bogged down on heavy acceleration. When it is idling the engine runs fine without any miss or hesitation. The fuel pump has about 23000 miles on it, fuel filter about 5000, and a new spider fuel injector set. It also has a new TPS, MAP, EGR, coolant temp sensor, fuel pressure regulator, crank angle sensor, coil pack, and new plugs(plugs were put in yesterday to try to cure the problem). The timing chain was changed last summer. I have been noticing antifreeze leaking out of the intake manifold gasket and I herd that could be the problem, but never got a definate answer about it. What could be the problem. Thanks in advance.

That sounds like the problem. IF you have an intake leak, it will allow too much air to the engine and cause it to bog.

Hestitating for months. Now, will not start. Cranks but does not turn. I do not hear the fuel pump hum when I turn the key. This means full pump bad, right?

possible, did you check and see if you have fuel pressure. if it is your fuel pump, make sure you install a new fuel filter also

[quote:35e36fb0e0="drstevedc"]Electrical problem
1996 Chevy Blazer 6 cyl Two Wheel Drive Automatic 154000 miles
----------------------------------------------------------------
Hestitating for months. Now, will not start. Cranks but does not turn. I do not hear the fuel pump hum when I turn the key. This means full pump bad, right?[/quote:35e36fb0e0]

I would check Fuel Pump Relay and check to see if it has a fuel shut off switch first. The fuel shut off switch should be located in the drivers side rear access panel.

To check relay find it in the under hood Power Distibution Box. Pull it and look for the numbers on it then look at the other relays and see if any match up and just swap them then try starting the vehicle.

Smarter to check simple inexpensive things before replacing the expensive.

vehicle does not have a fuel shut off switch

Engine Mechanical problem
1996 Chevy Blazer 6 cyl Four Wheel Drive Automatic

I have just replaced the intake manifold gasket and have it all put back together and when I start the car it sounds like it gets to much air when I accelerate. What could have I hooked up wrong?

Michael

It sounds like the intake manifold gasket has not been installed correctly, I would remove the intake and inspect the gaskets.

Hi Ive got 96 S10 Blazer 4.3 motor....Check engine lite was on...I think it was a PO101 or 102....I cleaned the throttle body....was ok for a couple days...now has slight hestitation when first starting out in the morning....and no codes....any ideas? Thanks Guys

check and see if you need a tune up like a cap and rotor and fuel filter. check for carbon tracking in the cap and see if your fuel filter is plugged up.

I have a 98 chevy blazer. I have been scouring automotive repair websites and have seen many blazers running into this problem. When the truck is cold it hesitates badly sometimes almost to the point of stalling out it seems but never quite gets there. I just had a full tuneup and have taken it into the shop 2 times already and the mechanic cannot figure out whats going on. As soon as it warms up (About half an hour of driving) it runs great. I just had my fuel pressure checked and it read at 55. The weird thing is that the computer is not throwing any codes at all, had it scanned twice. Cleaned the maf sensor and that didnt work, also had the Idle air control valve cleaned but not replaced, thinking about the coolant temp sensor but Im not sure if thats it... Please can someone clear this up for me once and for all!!!

Fuel pressure for your vehicle should be from 60-66 psi, anything less wont run properly.Does the pressure change when you rev the engine?

Im not sure if it changes on rev, but from what youre telling me it sounds like my fuel pump might be going bad??? I just had my fuel filter replaced so that cant be it. Anything else to try before I start into my fuel pump?

Low pressure is the pump,if the filter has been changed.The pressure should increase a little on therev if the regulator is working right. I do suggest an A/C Delco pump though

Is there any kind of test I could do to make sure that my fuel pump is going out before I go spending the 300 dollars to buy a new one?

Basically if the pump doesnt put out the pressure and the filter is new, the pump is all that is left

Engine Performance problem
1989 Chevy Blazer

Vehicle runs fine most of the time but suddenly will start stumbling (like suddenly lean mixture... includes the occassional backfire in carb). I have changed the fuel filter (it acts like a dirty fuel filter) but problem will suddenly appear even now. Suggestions?

Ok, so would this be something that a weekend warrior could do or would this be a shop only deal, because I know that the pump is in tank so... I wouldnt even know where to start.

This sounds like the fuel pump is weak, i would do a fuel pressure test.

Have to remove the fuel tank from the vehicle to get to it. Not too hard, but would need to be able to lift and support vehicle high enough to remove tank.

One thing became clear today when I drove it (it's
girlfriends vehicle so I had only driven it briefly before). When you start out on the road it runs fine. Real good in fact. After about 10-15 minutes when it has warmed up is when the issues begin. Then after cutting it off and letting it cool for 20 minutes, it was still too warm. I cranked it up again and same problem. Seems a COLD start and run it works fine but after warm up, problems! Oh, also, at one point I really put my foot into it and it hesitated and backfired but continued running. Tried it again and it didn't backfire again. How should I proceed... checking what in which priority (from most likely to less likely)?

Is there any way to make sure that its not my injectors that are going bad rather than my fuel pump or are you pretty sure that the fuel pump is whats causing the problem? Its so weird because it runs good on the first gear shift when you first start it up and then after you start driving it for a minute it start accelerating roughly. It makes me wonder about the fuel pump because it never dies when accelerating, just pops like its not getting enough fuel. ERRRR UH ERRR UH UH UH ERRRRUH ERRRR. Thats how it accelerates if that makes sense to you. LOL

Check the fuel pressure with a fuel pressure gauge, test the throttle position sensor and manifold absolute pressure sensor-also test the ignition coil

When the injectors start going bad you get single cylinder misfires, not necessarily lacking overall performance.It probably cant hang with the volume/pressure needed to run the engine, that is why it fades when you get going, lack of volume/pressure

Ok, last question for you. I have found some fuel pumps and they are around 200-300 dollars. Do I also need to replace my plastic tank or can I just replace the pump? I ony plan on having this car for 2 more years and I dont want to dump a bunch of money into it. I found this one for 75 dollars and I was wondering why it was so cheap.

[quote:c87fb96ad5="JaredWilske6185"]Engine Performance problem
1998 Chevy Blazer 6 cyl Four Wheel Drive Automatic 175000 miles

I have a 98 chevy blazer. I have been scouring automotive repair websites and have seen many blazers running into this problem. When the truck is cold it hesitates badly sometimes almost to the point of stalling out it seems but never quite gets there. I just had a full tuneup and have taken it into the shop 2 times already and the mechanic cannot figure out whats going on. As soon as it warms up (About half an hour of driving) it runs great. I just had my fuel pressure checked and it read at 55. The weird thing is that the computer is not throwing any codes at all, had it scanned twice. Cleaned the maf sensor and that didnt work, also had the Idle air control valve cleaned but not replaced, thinking about the coolant temp sensor but Im not sure if thats it... Please can someone clear this up for me once and for all!!![/quote:c87fb96ad5]I also have blazer doing same thing, just wanted to know if replacing fuel pump took care of the problem.

While the Blazer is idling, it runs great. The engine is a Vortec 4.3 High Output with approximately 216,000 miles.
The moment the acceleration pedal is engaged, the engine begins hesitating. It has had all of its belts, hoses, wires, plugs, distributor cap, replaced.
Would love suggestions.

Go to this link: https://www.2carpros.com/articles/engine-hesitates

HEEELLLPPP!! i drive 24miles to work its my only vehicle and I have the same problem on my 98 blazer 4dr 4.3 6cyl vortec.. I just had the fuel pump and filter replaced because my sending unit went so no gas gauge, and a slight loss of power accellerating so to be safe I replaced both.Well $550.00 later my gas gauge works, it starts no problem, starts to drive no problem yet when I step on the gas it bogs out can't tell if it's starving for fuel or choking from too much fuel not sure what brand of pump my garage used, they said drive it for awhile and see if it fixes itself..what should I do..

Blazer hesitates when I first start driving and then again after stop sign. After about 15 minutes of driving I have no more problems until the next day. It has now sometimes started a small backfire. Last year I had the fuel filter replaced along with a complete tuneup. I have had the distributor cap replaced again just in case it was moisture related,it is still happening, also had oxygen sensors replaced. Help!!

I would start by checking for vacuum leaks. Also, remove the EGR and make sure it doesn't have carbon plugging it or the intake where it attaches. Make sure it is working properly.

Let me know what you find.

[quote:e9edf418a8="Jacobandnickolas"]I would start by checking for vacuum leaks. Also, remove the EGR and make sure it doesn't have carbon plugging it or the intake where it attaches. Make sure it is working properly.

Let me know what you find.[/quote:e9edf418a8]
We tried the things you suggested and still having problems. Prior to your response we have had mechanics tell us it's the computer,or the fuel injectors, or the distributor. Even the dealer doesn't know what it is. We have replaced the thermostat, ignition coil, cleaned the mass air flow sensor, used seafoam to clean injectors. I am at the end of my rope with this problem if you have anymore suggestions I will gladly try them. Thankyou so much for your response.

I drove myself nuts with a similar problem. Thinking the engine was flooding or not getting enough gas.

Check your battery connections. I have side screw connections and the negative was rusted and also broke down the threads. You could wiggle the screw.

I replaced the bolt and the problem went away.

If one of the connectors is not bad, don't kill yourself trying to replace the battery wires.

Probably not that simple but at least check it out. Mine is a 1999 and has one of those high end duralast batteries

hello, i have a 1997 chevrolet blazer with a 4.3 v6 starts fine and runs good at idle but when you push on the gas pedal it acts like it is misfiring but has no fault code and the stft at idle is at -1.7 to 0

How long since a tune-up? What is the ltft? What is the 02 sensor showing, when problem occurs?

tune up was done about 6,000 miles ago. the b1 % ltft is -3.1 to -3.9 and the stft b2 % is -2.3 to 0 and the ltft b2 % is -9.3.
the o2 sensor b1 s1 % is -2.3 to 0 ,b1 s2 % is N/A and b1 s3 % IS N/A.

Why is bank 2 so different ltft? Both are within reason, but, I like to see it closer. Do a cylinder balance test, when problem is ongoing, anything show up?

Look at misfire counter spec, see if one cylinder has more misfire counts than the others. Start at that cylinder.