My Blazer will crank over but not start by itself. It needs starting fluid to start.

My Blazer will crank over but not start by itself. It needs starting fluid to start. I have replaced the fuel pump, filter, the whole spider injection system and it still will not start. My pressure is where it is supposed to be and it holds the pressure as well. I spray starting fluid in it and it will run at idle forever. Once I mess with the throttle it runs really rough and usually sputters out and dies. Once in a while it will run even when I open the throttle up but acts like its not getting enough fuel or the correct timing of everything because It'll start back firing and wanting t
Experienced mechanics share their insights in answering this question :
Hi there. If you have not replaced your EGR valve, mass air flow sensor or the TPS on your Blazer, you might want to start with these repairs. It is also possible that the throttle body itself is damaged, especially if you’re able to start it on fluid. If you want to avoid chasing parts and repairs, the best solution may be to have a professional mobile mechanic come to your location and complete a car is hard to start inspection.

How to Identify and Fix Common car Problems ?

Our sources include academic articles, blog posts, and personal essays from experienced mechanics :

The most common reasons a Chevrolet Blazer won`t start are a dead battery, an alternator problem, or failed starter.
The most common reasons a Chevrolet S10 won`t start are a dead battery, an alternator problem, or failed starter.
The most common reasons a Chevrolet S10 Blazer won`t start are a dead battery, an alternator problem, or failed starter.
relay center behind the glove door.
If the car cranks when you turn the key, but the engine won`t start, it could be because fuel isn`t getting to the engine. One potential reason for this could be dirty fuel injectors. Over time, the fuel injector nozzles can become clogged with rust, corrosion or debris.
When your engine cranks but won`t start or run, it could mean your engine is having trouble producing a spark, getting fuel, or creating compression. The most common causes are problems in the ignition (for example, a bad ignition coil) or fuel system (for example, a clogged fuel filter).
When an engine cranks for a long time before it starts, either spark or fuel is missing or weak and each has its own reasons. Most of the time, the air / fuel mixture has been disturbed and there is too much air or not enough fuel.
Bad ignition coil: When your dome light turns on but the engine doesn`t start, that means your battery is working but your ignition may be at fault. The ignition coil transforms a battery`s voltage into an electric spark. A damaged ignition coil means there`s not enough juice to do that.
The cause of this problem is usually one of 3 things – a failed starter motor, a bad connection between the battery and starter motor, or a blown fuse (if present) in line between the starter and the battery.
As the engine is cranked, the crankshaft position sensor indicates to the PCM that the engine has reached a minimum cranking speed of about 250-300 rpm. At that point, the PCM re-activates the fuel pump.
The fuel pump shut-off switch has a red reset button on top of it.
The fuel tank pressure sensor is part of the fuel pump assembly and is mounted on top of the tank or inside the tank. It`s part of the evaporative emissions system (commonly referred to as “EVAP”) and reads pressure in the fuel system to detect evaporative leaks, such as a loose or faulty gas cap.
Starting a vehicle with a bad crankshaft sensor can be risky and it`s unlikely to work. Disconnect the damaged sensor and try spraying a little starter fluid in the throttle body on your engine. Then, try cranking the engine to start the vehicle.
The crankshaft position sensor monitors the position and speed of the crankshaft and other parameters that play an important role when starting the engine. If the crankshaft position sensor is having a problem, the vehicle may have intermittent starting issues or not start at all.
A Bad Crankshaft Position Sensor

The crankshaft position sensor monitors the position and rotational speeds of the crankshaft. Without the crank sensor, the engine control module (ECM) wouldn`t know when to fire the fuel injectors and ignite the spark plugs.

An effective method to determine whether it`s your battery or alternator that`s gone bad is to connect jumper cables from a running vehicle`s battery to yours. After a few moments, try starting your vehicle. Once it`s started, remove the jumper cables — if your engine stalls, your alternator has probably gone bad.
This voltage range means the battery is in good condition for starting the vehicle. If the measured reading is less than 12.2 volts, the battery`s resting voltage is weak, which means it most likely needs to be charged or replaced.
Typically when your electrical accessories are working well, but it takes a few cranks for the engine to start, the issue is with the fuel or ignition system. In most cases, clogged or dirty fuel injectors, throttle body or mass air flow sensor will be the root source of this problem.
In that day, a cranking, no-start condition could easily be diagnosed by testing the available spark at the spark plug. If there was no spark, we touched a test light to the coil negative terminal to determine if the distributor contact points were switching the coil on/off (see Photo 1).

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

My Blazer will crank over but not start by itself. It needs starting fluid to start.
ANSWER : Hi there. If you have not replaced your EGR valve, mass air flow sensor or the TPS on your Blazer, you might want to start with these repairs. It is also possible that the throttle body itself is damaged, especially if you’re able to start it on fluid. If you want to avoid chasing parts and repairs, the best solution may be to have a professional mobile mechanic come to your location and complete a car is hard to start inspection.

Turns over but won’t start.. 2001 Chevrolet Blazer
ANSWER : Hello – your symptoms and diagnostic efforts still make me suspect that there isn’t adequate fuel pressure when you first try to crank it. The fact that it sometimes starts on the second effort reinforces this. If the fuel check valve/fuel pressure regulator is allowing the fuel pressure to completely drop overnight, the fuel pump has to run longer to bring pressure up to where the injectors actually deliver fuel. Leaving the fuel pressure gauge attached overnight, so that you can watch fuel pressure on first startup will provide guidance as to whether this is the case. I recommend a hard start inspection performed by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, and give you an accurate assessment of damage and cost estimate for repairs.

Fuel pump engages. Batery good, alternator good volts, jump start helps when wont start. Temp does not matter. Intermittent?
ANSWER : Hello. Thank you for writing in. There are several reasons your vehicle may only start when jump starting. The first and most common is a build up of resistance that is causing you to need a boost of voltage to get the engine started. This may be due to poor battery cables, a bad ground connection, a poor starter solenoid, and a couple of other issues. The first thing you want to do is perform a visual inspection of the starting system. Make sure there is no corrosion build up in the battery cables. You can also check the resistance across these wires and make sure you have a solid connection between components. You then want to make sure the starter solenoid is doing its job. It is responsible for taking the small amount of electricity sent by the ignition and turning it into a huge electrical charge that is strong enough to push over the engine with the help of some gear ratios in its favor. Do some more testing, and stick to the basics before assuming its something seriously complicated.

72 Chevelle cranks but won’t start and has to be flooded but smell no gas
ANSWER : Gasoline is generally not usable after 3 to 6 months. If gasoline has been stored in the vehicle for a lengthy time, the problem is likely that there is just simply nothing to combust. The volatile components in the gas have evaporated and other compounds in the gas have turned to varnish and gum, possibly plugging up the carburetor. If the tank was drained though and the fuel in the fuel system is fresh, please simply request a no start diagnostic and the responding certified mechanic will pinpoint the cause of the no start condition. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

The car is having trouble starting up ,70 percent of the time it starts right up. the other 30 percent, it randomly won’t start its
ANSWER : Hey there thanks for writing in about your 1998 Honda Accord. This could be a few things. A faulty ignition switch, a failing crank sensor, or possibly other faulty sensors could be the cause. To have this taken care of, consider having a certified technician, such as one from YourMechanic, come to your car’s location to diagnose and repair the hard start issue.

Car was sometimes not starting, not even cranking when i turned the key then after a few times itd start. Now it ont start at all
ANSWER : Hi there:

Without being there to inspect your vehicle, or having information about what type of car, truck or SUV you own, it’s very hard for us to give you some advice. You might want to have a professional mobile mechanic complete a car is hard to start inspection; so they can come to your location and determine why your vehicle is having these issues.

My car starts fine but always like once a month it doesn’t start it cranks ok but it will not start if I let it sit for 6 hours
ANSWER : Hi There,
What you are describing sounds like an ignition coil that may be failing. Ignition coils are prone to this type of erratic functioning or heat cycling when they are beginning to fail due to the temperature fluctuations under the hood which ultimately cause them to shut down causing the car to only run after cooling down for 30-40 minutes. Ignition coils are coated with a varnish-like insulation that becomes brittle over time after being stretched then contracted repeatedly The insulation develops small fractures that open when heated and close when cooled. When open, they allow shorting of coil windings and decrease or eliminate the coil’s ability to function. This process will repeat itself continuously until the coil ultimately fails completely and must be replaced. I would recommend having a professional from YourMechanic come to your location to diagnose and inspect your ignition system.

Vehicle won’t start, once it’s jump started it only stays running until you turn it off, then it work start again without jumping.
ANSWER : Hi there. There could be two problems here. It is possible that your battery is bad and will not take a charge from your alternator while driving. In that case every time you shut your car off you will not have enough juice to start it again. Inspect your battery – it should have at least 12.5 to 13 volts to start your car, if it doesn’t you will need to replace the battery. The second problem could be that your alternator is bad and not charging your battery, in this case you will need to replace your alternator. Both the battery and the alternator can be tested in your car. If you would like to have the car checked for you, a certified professional from YourMechanic can come to your car’s location to diagnose the starting problem and proceed with repairs.