The car wont start it cranks but no start

Car Will Not Start And OBD Code p0420

I just put a scanner on and got a code p0420 ,my problem is the car won't start it cranks but no start ,day before yesterday it started no prob today no go this has happened a few times ,help please

Answer:

Diagnostic Trouble Codes (DTC) P0420 and P0421 indicate that bank 1 catalyst system efficiency is below the acceptable threshold.

 

Most of the time this code requires cat converter replacement to fix the converter is no longer efficient. This would be the passenger side. This will not cause a no start check for spark and fuel I would suspect a fuel pump or fuel pump relay is causing this no start. Make sure you have crank signal from the crank position sensor and check the fuel inertia shut off switch.

I would check for fuel pressure when it happens. I would lean more towards a fuel pump or fuel pump relay swap the relay with a headlight or AC relay I believe they are the same compare the part number on them.

Make sure the crank sensor reads cranking rpm about 100-150 rpm when cranking also check the wire to the crank sensor they chafe on the AC compressor.

Car wont start when cold

2000 grand marque 130000 miles 302 motor i believe had plugs replaced at dealer they said no bad codes in computer good gas pressure only hard starts when cold when engine warm runs fine.

Answer:

Your 2000 Grand Marquis has a 4.6L V8. But that's OK.

It sounds like you have a fuel pump problem on cold start.

One way to verify that this is the problem, in the morning when the engine is cold, turn the key to on, NOT START, just on. Leave it there for 3 seconds then turn it to off and then repeat this process 3 times.

Then try to start the vehicle.

 

If it starts right up, the problem is the fuel pump.

What is happening, overnight or when the vehicle sits for a period of time to cool down, the fuel is returning to the fuel tank. The fuel pump has a check valve in the pump that keeps the fuel in the fuel lines to the engine for easy starting.

When the check valve goes bad, all the fuel in the fuel lines drains back to the fuel tank. Then you have to crank, or cycle the key in the ignition to resupply the fuel lines to the engine.

The check valve is part of the fuel pump itself and is only available with the complete fuel pump assembly.

You will get no codes and the fuel pressure will still be good with the engine running.

You will have to cycle the key on to off.

The fuel pump will only come on for 3 or4 seconds and then turn off. That is why you will have to cycle the key.

If your Grand Marquis has rear air ride suspension, the noise may be the air pump for the rear air springs.

The fuel smell is from pumping the pedal. On fuel injected vehicles, you do not have to step on the gas pedal to start the vehicle, only on carburettor engines from years ago.

 

To repair the problem, the fuel pump in the fuel tank will have to be replaced. But if you can live with cycling the key on cold starts, you can put it off till later. It will not cause any other issues or problems.

Only the fuel pump itself will cause this, the check valve is part of the pump.

Like I stated, if you can live with cycling the key 3 times when the engine is cold, then you can wait till later to replace the pump.

Security Light ON and Car wont start'

Chevrolet Blazer 4.3 V6 2001 R/H drive.Security light is ON and car will not start.Please help.

This is a common problem with the Passlock security system...turn on the ignition key and try to crank the engine..than let go of the key and wait for 10 minutes, until the security lamp goes off...when it does, try to crank the engine again...if it doesn't fire up then try the 30 minute reprogram procedure.

Another possibility can be shorted fuse or low battery:

I think you may have a shorted battery...the dome lamps and the door locks are another indication of this. Also, these battery positive cables are known for coming slightly loose and driving the on board computers crazy. Check the cables for tightness, if they're loose you'll need to recharge the battery..if they are tight, you'll need to take the battery out and have it tested...it may very well be defective. If the battery is good and cables are tight, be sure there is no corrosion on the cables or where the negative cable attaches the the engine.

Try the 30 minute relearn, otherwise it may have a Passlock Sensor failure or other anti-theft component failure...which will need to be scanned with a dealer level scan tool. There is no way to bypass this style of alarm system, and the keys are not programmable either...try the procedure below a couple of times..

30 Minute Learn Procedure

Notes

Turn ON the ignition, with the engine OFF.

Attempt to start the engine, then release the key to ON (vehicle will not start).

Observe the SECURITY telltale, after approximately 10 minutes the telltale will turn OFF.

Turn OFF the ignition, and wait 5 seconds .

Repeat steps 1 through 4 two more times for a total of 3 cycles/30 minutes (the vehicle is now ready to relearn the Passlock(TM) Sensor Data Code and/or passwords on the next ignition switch transition from OFF to CRANK). IMPORTANT: The vehicle learns the Passlock(TM) Sensor Data Code and/or password XXXXX the next ignition switch transition from OFF to CRANK. You must turn the ignition OFF before attempting to start the vehicle.

Start the engine (the vehicle has now learned the Passlock(TM) Sensor Data Code and/or password).

With a scan tool, clear any DTCs if needed (history DTCs will self clear after 100 ignition cycles).

 

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If the relearn isn't working than there is a fault in the Passlock System..see the bullitin below...Now the first step is to get a scan of the BCM (Body Control Module) codes and see if any are related to this failure. If you have access to a voltmeter, we can rule out the ignition switch as a failure, and the starter...incase the security lamp is malfunctioning and correctly indicating a security problem.

Security System - Lamp ON/No Start/DTC B2960 Set Notes

File In Section: 08 - Body and Accessories Bulletin No.: 01-08-56-001A Date: June, 2001 Subject: Security Lamp Illuminated on the IP, Engine Stalls, No Start, DTC B2960 (Security System Sensor Data Incorrect but Valid) Set (Inspect and Repair Cause of DTC B2960) Models: 1998-2001 Chevrolet and GMC S/T Pickup and Utility Models (S10, Sonoma, Blazer, Jimmy) 1998-2001 Oldsmobile Bravada This bulletin is being revised to add information on inspecting for electrical intermittent conditions and important connector C211 tightening steps. Please discard Corporate Bulletin Number 01-08-56-001 (Section 08 - Body and Accessories). Condition Some customers may comment on the following conditions. These symptoms may be intermittent. ^ Security lamp illuminates while driving. The Security lamp may be On or Off. ^ Security lamp is illuminated. ^ The engine cranks but will not start and the Security lamp is flashing. ^ The engine starts then stalls and the Security lamp is flashing. Cause Condition(s) may be due to an incorrect Passlock(TM) sensor voltage (which is intermittent) received by the body control module (BCM) from the Passlock(TM) sensor due to the following conditions. Most intermittent conditions are caused by faulty electrical connections or wiring. ^ A 7 ohm variation in the sensor ground circuit wiring, circuit 1057 ^ A 100 ohm variation in the Passlock(TM) sensor signal wiring circuit, circuit 1836 Inspect for the following items: ^ Broken wiring inside the insulation. ^ A poor connection between the male and female terminal at a connector. Refer to Testing for Proper Terminal Contact under Testing for Intermittent and Poor Connections in Wiring Systems for the specific procedure. ^ A poor terminal to wire connection. Some conditions that fall under this description include poor crimps, poor solder joints, crimping over the wire insulation instead of the wire itself, and corrosion in the wire to terminal contact area. ^ Wire insulation that is rubbed through. This causes an intermittent short as the bare area touches other wiring or parts of the vehicle. ^ A poor connection between the male and female terminal at a connector. This poor connection may be the result of contamination or deformation. ^ Contamination may be caused by the connector halves being improperly connected. A missing or damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and dirt can also cause contamination. Contamination, usually in the underhood or underbody connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit. - Separate the connector halves. - Visually inspect the connector halves for contamination. Contamination may result in a white or green build-up within the connector body or between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An underhood or underbody connector that shows signs of contamination should be replaced in its entirety including the terminals, the seals, and the connector body. ^ Deformation is caused by probing the mating surface of a connector terminal without the proper adapter, improperly joining the connector halves. or repeatedly separating and joining the connector halves. Deformation. usually to the female terminal contact tang, can result in poor terminal contact causing an open or intermittently open circuit. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly different between a good terminal and a suspect terminal. Replace the female terminal in question.

Correction Notes

Have any of the following components had service recently? ^ The BCM ^ The ignition lock cylinder case assembly ^ The PCM/VCM If any of the above components have been replaced, the Passlock(TM) Reprogramming Seed and Key (10 Minute Re-Learn) procedure must be performed before any diagnostic procedures are performed. To assist in diagnosis. the following steps are provided. 1. Does the engine crank but not start? If yes, use the Engine Cranks but Does Not Run diagnostic information in the Engine Controls sub-section of the applicable Service Manual. 2. Observe the security indicator lamp in the top right corner of the instrument panel when you turn the key to the RUN position. Does the indicator lamp show any of the following conditions? ^ Lamp is On for 5 seconds, then goes Off. This is normal operation. The engine should start and run. ^ Lamp is On and does not go Off. A problem is detected but the engine starts. This indicates that the fault occurred when the engine was running. ^ Lamp does not come On. This is abnormal operation. Use the Security Indicator Inoperative diagnostic in the Theft Deterrent sub-section of the applicable Service Manual. ^ Lamp flashes On and Off. This indicates a problem has been detected this key cycle by the Passlock(TM) system and the engine may not start. No reason to get rid of it over this, might be a little difficult to narrow down without a dealer level scan tool..but we make some tests with a voltmeter. below is the fuse box layouts and antitheft wiring schematic. Security Indicator: If it is always on, may indicate a faulty alarm module or might just be a glitch... Fuses: Do you have access to a voltmeter? I'd like to make a test at the starter and be sure how much voltage we're getting on the remote line... If the security light has gone out...that means the immobilizer system should be inactive.. the two wiring schematics above are for the immobilizer and starter..but the immobilizer is part of the computer ciruit and you would need a GM level scan tool to see if it is really interfering with the starting... Does the engine crank over now? Do you have access to a voltmeter?  below is the underhood fuse box components...it's unusual for the system to act this way after the battery going flat, now there may be a bad Passlock Sensor or the BCM (Body Control Module) which uses the Passlock Sensor signal...if you could scan the BCM codes, we would not for sure what's going on here. With the enigne starting and dying, it further entails a security failure. I would keep trying the 30 minute learn...i've had to try them for hours before, and than it would take.. engine turns over with no compression/ will not start. i have a 4.6 overhead cam . turns over but sounds like it has no compression. will not start. took lefthand valve cover off and timing chain is not broken. have not removed the right cover as of yet.need to know how to complete the cover removal and how to check the timing , did it jump time?if so , how do i fix it? Answer: In some cases, the fast engine turning could be due to an abundance of fuel present. Every time in my experience that a 4.6L V8 spun fast like that, I was able to start it by putting the accelerator to the floor and cranking it for 10-15 seconds at a time. Doing this cranks the engine while shutting fuel pressure off. The only thing you have to be aware of is that you need to allow the starter to cool and make sure the battery is fully charged. This will help. Thanks.

Other Warning Light(s) On

Troubleshoot Other Warning Light(s) On Car Control Panel

Temp Warning Light On

Your engine is overheating. Stop driving immediately and turn the engine off. Continuing to drive risks causing expensive engine damage such as a blown head gasket, or cracked or warped cylinder head.

Low oil pressure or loss of oil pressure can be caused by a low oil level in the crankcase, a worn or damaged oil pump, or worn engine bearings.

Allow the engine to cool down for several hours before you attempt any further diagnosis. A hot engine can be very dangerous because of steam pressure inside the radiator and coolant reservoir. Do NOT attempt to add coolant until the engine has cooled down and the radiator cap or reservoir cap can be safely opened. Overheating can be caused by a low coolant level (check the radiator, water pump, and hoses for leaks), coolant leaks inside the engine (leaky head gasket or cracks in the head or block), a stuck thermostat, or a cooling fan that isn't working (bad fan clutch, fan motor, or fan relay).

Oil Light On

Oil pressure is dangerously low. Stop driving immediately and turn the engine off. Continuing to drive risks the rapid failure of bearings and camshaft in your engine. Low oil pressure or loss of oil pressure can be caused by a low oil level in the crankcase, a worn or damaged oil pump, or worn engine bearings. In older high mileage vehicles, it is not uncommon to see the oil warning light flicker at idle because of internal engine wear. Check the oil level before restarting the engine. If low, check the engine for leaky gaskets and seals, or a loose oil filter. If no leaks are seen, the engine may be burning oil because of worn valve guides, rings, and/or cylinders. Add oil to bring the level on the dipstick up to the full mark, then start the engine to see if the light goes out. If the light does not go out and the engine is making noise (ticking, rattling, clicking, rapping sounds), it may not be getting normal oil pressure – or it may have suffered damage because of the loss of oil pressure. You’re looking at an overhaul or buying another engine.

Charging, Alt or Gen Light On

Your charging system is not putting out its normal voltage or current. This means one of two things: either the alternator (generator) has died, or the belt that drives it is slipping or has broken. On vehicles with serpentine belts, losing a belt means you lose everything that the belt drives: the water pump, alternator, power steering pump, and A/C compressor. The A/C compressor you can live without, and with sufficient upper body strength you can still steer without the PS pump. But your engine isn't going to stay cool for long without the water pump. So stop, turn the engine off and take a look under the hood to see if the belt is still intact. If the belt is still on and appears to have normal tension, the alternator has probably failed. You can probably drive your car a few miles or up to 30 minutes or so on the juice that’s left in the battery, but don’t count on going too far because, without the alternator, the battery will run down very quickly. And once voltage drops below a certain level, the engine electronics will shut down. The fix? Check the charging system’s output at the battery terminals with a voltmeter. Normal charging voltage should be about 13.5 to 14.5 volts (it varies some with temperature and load). If you see 12.6 volts or less (which is base voltage for a fully charged battery), you need to have the alternator tested (many parts stores can do this for you). Or, with the ignition in the accessory position and the lights on, the battery voltage should remain near 12 volts for several minutes. If not, you have a weak battery.

ABS or Brake Light On

If only the ABS light is on, your vehicle should still have normal braking (possibly without power assist, though, depending on what type of ABS system it has). But if the brake light is on (with or without the ABS light), it may indicate a serious hydraulic problem in your brake system. On most vehicles, the brake warning light will come on if a safety switch detects a difference in pressure between the brake circuits when the brakes are applied. This may indicate a leak and loss of pressure in one of the circuits. On some vehicles, there is also a brake fluid level sensor in the brake fluid reservoir on the master brake cylinder. If the fluid level drops, it may turn on the warning light. Either way, the first order of business is to stop the vehicle and check the fluid level in the master cylinder. The fluid level will drop somewhat as the brake linings wear, but a sudden drop in the level usually means there’s a leak in a brake line, hose, caliper or wheel cylinder. Do NOT drive the vehicle until the problem has been diagnosed and repaired.

Turning the Check Engine Lamp Off

As a rule, the Check Engine Light will remain on as long as a fault persists. If an intermittent fault does not reoccur after three consecutive trips, the MIL lamp will go out but the code will remain in memory. If the fault does not reoccur for 40 trips, the code will be erased. The only safe way to clear fault codes and turn the MIL lamp off is to use a scantool. On many pre-OBDII vehicles, all you had to do was disconnect the battery or pull the PCM fuse to clear the memory and turn the Check Engine Light off. If the problem had not been fixed, the Check Engine Light would eventually come back on. But this procedure should NOT be used on OBDII cars for the following reason:

WARNING: On many OBDII cars, pulling the PCM fuse or disconnecting the battery may NOT clear the codes - and may cause a loss of important information that the PCM needs to function correctly. On some vehicles, loss of power to the PCM may cause it to forget transmission settings, climate control functions, and other essential data. This, in turn, may require the use of a scantool and a special re-learning procedure to reset the PCM.

Here’s another thought: codes contain important diagnostic information you or somebody else might need to further troubleshoot and repair the system. If the codes are cleared, it may take some time for the codes to reset - which will delay diagnosing and repairing the fault. The best approach to turning off the light, therefore, is to read out the codes, and clear the codes carefully.

Troubleshoot All types Of Car Problem With proper Solutions

http://carrepairworld.blogspot.com/2015/03/how-to-repair-car-problem.html

 

Know Exactly How Each And Every Part In Your Car Works

http://carrepairworld.blogspot.com/2015/04/how-does-it-work.html

 

Troubleshoot Car OBD Codes.Know Exactly What Each Code Means?

http://carrepairworld.blogspot.com/2015/04/vehicle-obd-ii-codes.html

Check Engine Light is On

Engine Warning Light Is On

Today’s cars are controlled by a Powertrain Control Module (PCM), your engine’s computer. If you want to repair or modify your car’s performance, you need a scantool to communicate with the PCM.

Symptoms:

• Check Engine Light on
• Poor Acceleration
• Poor Fuel Economy
• Rough Idle

Probable Cause(s):

• Oxygen Sensors Codes (P0130 to P0167)
• EVAP Code (P0445)

That pesky Check Engine Light, the “Malfunction Indicator Lamp” or “MIL” for short, is on because your vehicle’s computer self diagnosed a fault that could cause your vehicle’s emissions to increase. It doesn’t necessarily mean your vehicle is polluting – or has a serious problem – but it might. So the light is on to let you know something is amiss that needs your attention. Trouble is, you don’t know WHAT the trouble might be. It might be something and could lead to a break-down or cause expensive engine damage, or it might be something minor like a loose gas cap (yes, the on-board diagnostics on 1996 and newer cars can even detect a loose, missing, or leaking gas cap). There’s no way to know what the problem is without talking to your vehicle’s computer. How do you do that? By plugging a diagnostic scantool like AutoTap Express DIY into your vehicle’s diagnostic connector, usually found under the dash near the steering column. This unlocks the secrets that have turned on your Check Engine Light. AutoTap Express DIY will give you the information you need to understand how to diagnose and repair the most common problems in today’s cars, light trucks and SUVs. Whether you perform the repairs yourself, or use the information to better understand what your mechanic is doing, it pays to understand what is going on.

Don’t be a Parts Swapper

The number one mistake made by do-it-yourself mechanics is “parts-swapping”. This expensive practice leads to the replacement of hundreds of dollars of perfectly good parts. At best, a parts-swapper wastes time and money. At its worst, a parts-swapper creates new problems where none existed. Armed with the proper tools and the information from AutoTap Express DIY, you will be prepared to tackle the most common problems found on today’s vehicles, without being a parts-swapper.

The On-Board Diagnostic System - OBDII

When a fault is detected, the Onboard Diagnostics System (OBDII) records a “Diagnostic trouble code” (DTC) in the computer’s memory. The code number corresponds to a particular type of fault. The code might not tell you which component has failed or why, but it will tell you which emission control system or sensor circuit the fault is in, or that your engine is misfiring or running rich (too much fuel) or lean (not enough fuel). When a basic code reader is plugged into your vehicle’s diagnostic connector, it will display any diagnostic trouble codes that are found. The least expensive code readers just give you a number, while the better ones also give you the definition of the code too. You can read codes and get an idea of what’s wrong – and you can even clear the codes from the computer’s memory to turn out the MIL lamp (at least temporarily). But a code by itself isn’t the whole story. Take a code P0171 or P0174. These are codes that indicate your engine is running lean. A lean air/fuel mixture can be caused by any number of things, and may cause symptoms such as a rough idle, hesitation, or stumble when accelerating, hard starting, a loss of power or an emissions failure. Okay, so your engine is running lean. Now what? The next step up the diagnostic ladder is to use AutoTap Express DIY. It can actually provide real diagnostic information. What kind of information are we talking about? Real time sensor data. This is the meat and potatoes of onboard diagnostics and is the data that real technicians rely on to diagnose and repair today’s vehicles.

The diagnostic connector on your vehicle can provide a wealth of information, things like engine speed, engine load, air flow, ignition timing, coolant temperature, inlet air temperature, throttle position, sensor voltages, what’s going on with your engine’s fuel management system, the status of various switches and devices, and more – in fact, up to several hundred different readings are available on some cars depending on the make and model year.

Diagnostic scantools like AutoTap Express DIY:

• Save you money
• Save you time
• Keep your mechanic honest

Knowing what’s causing your problem gives you the option to either fix the problem yourself or to take it to a professional for repairs. If you choose the latter, you won’t be going in blind. You’ll be armed with data that can save diagnostic time and, hopefully, some of your money. In many instances, the Check Engine Light is on because a sensor has failed and needs to be replaced. Some sensors are relatively inexpensive and well within the abilities of a do-it-yourselfer to replace. Some sensors, on the other hand, are quite expensive. A mass airflow sensor might cost a couple hundred dollars or more. So you want to be sure of your diagnosis before you replace such an expensive part – especially since most dealers or parts stores won’t take returns on electronic parts once they’ve been installed.

Troubleshoot All types Of Car Problem With proper Solutions

http://carrepairworld.blogspot.com/2015/03/how-to-repair-car-problem.html

 

Know Exactly How Each And Every Part In Your Car Works

http://carrepairworld.blogspot.com/2015/04/how-does-it-work.html

 

Troubleshoot Car OBD Codes.Know Exactly What Each Code Means?

http://carrepairworld.blogspot.com/2015/04/vehicle-obd-ii-codes.html