Dan Ferrell schrijft over doe-het-zelf auto-onderhoud en reparatie. Hij heeft certificeringen in automatiserings- en besturingstechnologie.
1. Lege batterij
2. Slechte startmotor of systeem
3. Defecte dynamo
4. Verstopt brandstoffilter
5. Defecte brandstofdrukregelaar
6. Slechte brandstofpomp
7. Defecte bobine of module
8. Defecte krukaspositiesensor of nokkenaspositiesensor
9. Groot vacuümlek
10. Defecte distributieriem
Verderop in dit artikel helpen we u door enkele tests te navigeren en te beslissen welk probleem van u is, zodat u weer op weg kunt.
Uw probleem past vaak in een van deze vijf categorieën:
Als u te maken heeft met een motor die weigert te starten, kunt u geluiden, of het ontbreken daarvan, als diagnostisch hulpmiddel gebruiken. Geluiden helpen u zich te concentreren op het systeem of de systemen waar het probleem zich zou kunnen bevinden, waardoor andere potentiële probleemplekken worden geëlimineerd.
Als u een enkele, stevige klik hoort wanneer u probeert de auto te starten, kan het probleem in de startmotor of het circuit zitten.
Een ratelend geluid dat onder de motorkap vandaan komt wanneer u de motor probeert te starten, kan wijzen op een onvoldoende opgeladen accu, losse of gecorrodeerde accupolen of een probleem met de dynamo of het laadsysteem.
Als u niets hoort wanneer u probeert uw auto te starten, controleer dan op:
Wanneer u de contactsleutel omdraait om de motor te starten, hoort u misschien het gebruikelijke gebrul van de motor, maar de motor start nooit. Zo ja:
Raadpleeg indien nodig de Bronnen onder aan dit bericht voor hulp bij deze en andere problemen.
Vaak is een no-start-toestand terug te voeren op een storing in het brandstofsysteem. Als uw motor draait maar weigert te starten, voert u deze eenvoudige test uit. Deze test kan u vertellen of het probleem te maken heeft met de brandstoftoevoer.
Als de motor een paar seconden start en dan uitvalt, is uw probleem hoogstwaarschijnlijk brandstofgerelateerd. Controleer het brandstoffilter, de brandstofdrukregelaar en de brandstofpomp, zoals aangegeven in de volgende paragrafen.
De volgende video laat zien hoe u startvloeistof gebruikt.
Nu je een idee hebt welk systeem onderzocht moet worden, kun je beginnen met onderzoeken. De volgende tien secties behandelen de tien meest voorkomende fouten waarmee u waarschijnlijk te maken krijgt als uw auto weigert te starten, en hoe u elke mogelijke fout kunt controleren.
Dit is een van de meest voorkomende redenen waarom een auto niet wil starten. Een auto-accu kan tot zes jaar meegaan, afhankelijk van het onderhoud en de bedrijfsomstandigheden. Extreme weersomstandigheden verkorten bijvoorbeeld de levensduur.
Het is echter niet ongebruikelijk dat een batterij plotseling zijn lading verliest.
Controleer de aansluitingen van de accupolen. Verwijder corrosie en zorg ervoor dat de klemmen goed vast zitten. Controleer vervolgens het elektrolytpeil als de batterij verwijderbare doppen heeft.
Wanneer uw auto weigert te starten, zorg er dan voor dat uw batterij goed is opgeladen. U kunt een digitale multimeter (DMM) gebruiken om de laadstatus te controleren.
Om de laadstatus van de batterij te controleren:
Als u de batterij moet opladen, gebruik dan indien mogelijk een langzame lading. Dit helpt de batterijconditie te herstellen.
Uw plaatselijke auto-onderdelenwinkel kan controleren of uw batterij nog goed is.
De startmotor en het circuit zijn andere veelvoorkomende bronnen van problemen. Dit systeem kan de boosdoener zijn als u een stevige klik hoort wanneer u probeert de motor te starten.
Er kan een probleem zijn met de startsolenoïde, het relais of de startmotor. Controleer indien nodig de schakeling met een spanningsvaltest. Bekijk de Bronnen onder aan dit bericht voor hulp bij deze test.
Also, your local auto parts store will check the starter motor for free, but you'll need to remove the starter from the vehicle.
Along with a dead or bad battery, alternator issues are one of the most common reasons for a no-start condition.
Usually, the charging system will turn on a warning light on the dashboard alerting you about a fault in the system. However, there are many reasons a charging system may fail to deliver a charge to the battery or electrical power to other systems in the vehicle.
Points to check:
Keep in mind that a corroded battery terminal could be a sign of an alternator overcharging the battery.
If you don't want to do it, your local auto parts store will check the alternator for you.
Most manufacturers recommend replacing the fuel filter every one or two years. Replace your fuel filter as recommended.
Although many fuel filters include a bypass valve in case the filter clogs, not all come equipped with this valve. Besides, rust and other sediments in the fuel tank can make their way to the fuel filter and clog its filter element.
Before giving out completely, a clogging fuel filter will give you one or more signs. For example, you may notice a lack of engine power at high speeds, difficulty starting the engine, or poor acceleration.
Check your repair manual to inspect the fuel filter and system in your particular model, if necessary.
If you suspect insufficient fuel reaching the injectors, do the quick fuel system delivery check as described in the second section of this post.
A fuel pressure regulator (FPR) limits the amount of pressure buildup in the system, typically to between 35 and 45 psi. Check your vehicle repair manual for your model specifications.
But FPRs can fail. If the internal diaphragm begins to leak fuel into the intake manifold, pressure will drop, and the cylinders will be flooded with fuel, making the engine hard to start.
Also, if too much raw fuel reaches the catalytic converter, the Check Engine Light (CEL) will begin to flash on your dashboard.
If you suspect insufficient fuel reaching the injectors, do the quick fuel system delivery check as described in the "Pre-Diagnostic 2" section of this article above.
You can perform a few FPR tests at home. See the Resources section at the bottom of this article for some help.
Fuel pumps have a long service life. They can last 80,000 miles or more. If your fuel filter and fuel pressure regulator are fine, but you have a fuel issue, probably your fuel pump is bad.
When turning the ignition key to the "On" position, before trying to start the engine, you should hear a buzzing sound for a couple of seconds. This is the sound of the fuel pump motor being activated to prime the fuel delivery system.
If you don't hear this sound, it may be that:
To verify a fuel delivery issue, do the quick fuel system delivery check as described in the second diagnostic section near the top of this article.
Also, check the repair manual for your particular model to see how to test the fuel pump, if necessary.
For the most part, ignition coils or modules are pretty reliable. Unlike spark plugs, wires, and distributor caps (depending on the model), an ignition coil or module doesn't require much attention.
However, they can fail from time to time. The conditions under which they operate, like heat, vibration and other engine performance issues, can have an adverse effect on any of these components after many miles of operation.
Older vehicle models used a single ignition coil and module to deliver a spark to the spark plugs. Newer models may use a module and one coil per spark plug. A failed coil or module in one of these models will certainly prevent the engine from starting.
You can use a spark tester to verify the presence and condition of the spark. You can buy one at your local auto parts store. If possible, get an adjustable spark tester you can use in different vehicles.
The Resources section at the bottom of this post, and your vehicle repair manual, can help you check an ignition coil or test for the presence of a spark in the ignition system.
The crankshaft position (CKP) sensor monitors engine speed, and the camshaft position (CMP) sensor tracks the position of the camshaft.
The electronic control module (ECM), the car's computer, uses the signal from both sensors to control fuel injection operation, direct ignition, and, depending on vehicle model, the variable valve timing system.
If any of these sensors fails, your car may fail to start.
Sometimes, depending on the specific fault, a bad CKP or CMP will trigger the check engine light (CEL). Whether the CEL illuminates on your dashboard or not, it's a good idea to scan the computer memory for potential diagnostic trouble codes (DTCs) that can help you diagnose a no-start condition.
If you don't have a scan tool, your local auto parts store may download DTCs for you without cost.
Also, check your vehicle repair manual. And, within the Resources section at the bottom of this post, you'll find links to other posts to help you check these sensors yourself, if possible.
Major vacuum leaks are not common, but they definitely happen. A vacuum leak can make the air-fuel mixture too lean, preventing the engine from starting.
A leak may come from a vacuum line, intake manifold gasket, throttle body gasket, leaking EGR valve gasket, power brake booster or positive crankcase ventilation (PCV) valve.
Vacuum leaks can be tricky to find. You can visually inspect every vacuum hose and trace it with your hand, feeling for tears or damaged spots. Also, pay attention to hissing sounds that may indicate a leak.
A leaking gasket is harder to detect, though, unless you have a smoke machine designed for this purpose.
If necessary, consult your vehicle repair manual.
You won't see this type of failure often. Timing belts can last between 50,000 and 100,000 miles or more, depending on your particular model. And if you have a timing chain rather than a belt, you may never have to worry about replacing it.
Still, if you've checked the usual suspect without success, check for a failed timing belt or chain.
The engine's crankshaft and camshaft are joined by a timing belt or chain through a series of sprockets. When this belt or chain brakes or wears out, or the tensioner fails, the crankshaft won't be able to rotate the camshaft anymore, making it impossible to start the engine.
Checking for a failed timing belt or chain:
On a vehicle fitted with a distributor, you can remove the distributor cap and try to fire up the engine. If the distributor rotor doesn't move, most likely your timing belt or chain, or one of the system components, has failed.
On models with multiport fuel injection systems, sometimes it's possible to remove the timing belt or chain cover to check for camshaft movement while trying to start the engine. Or you may be able to remove the oil cap from the valve cover, or the cover itself if necessary, to check for valve movement while trying to start the engine. If there's no movement, it's time to check the belt, chain, or system components.
If the camshaft rotates, you may still want to verify ignition timing. If the belt or chain has skipped some sprocket teeth, it may be difficult or impossible to start your engine.
Consult your vehicle repair manual to check crankshaft and camshaft synchronization.
Of course, there are other model-specific components or systems that can prevent your vehicle from starting. Bijvoorbeeld:
Consult the repair manual for your specific make and model for help on these and other systems or components.
To sum up, when your car won't start, begin your diagnostic with the most simple components or obvious potential problems, as in Diagnostics 1 and 2 at the beginning of the article:
Then you can start checking the alternator, starter motor, ignition, fuel system pressure, and their circuits.
Most of the time you'll be able to fix the problem yourself. Sometimes, you will need to replace a fuel pressure regulator, ignition coil, module, or fuel pump, or fix a vacuum leak.
See the Resources below for diagnostic ideas if you have narrowed your problem down to a particular system.
This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional. 
Hier zijn tien redenen waarom uw auto niet start...
...In vijf algemene categorieën
Een paar aanbevelingen voordat u met uw diagnose begint
Pre-Diagnostic 1:Geluid gebruiken als diagnostisch hulpmiddel
Welk geluid hoor je wanneer je de motor probeert te starten?
Pre-Diagnostic 2:een snelle brandstofsysteemleveringscontrole
Nu:de tien veelvoorkomende fouten en hoe u deze kunt controleren
1. De batterij is leeg
2. Slechte startmotor of systeem
3. Faulty Alternator
4. Fuel Filter Clogged
5. Faulty Fuel Pressure Regulator
6. Bad Fuel Pump
7. Faulty Ignition Coil or Module
8. Faulty Crankshaft or Camshaft Position Sensor
9. Major Vacuum Leak
10. Failed Timing Belt
A Few Unusual Additional Possibilities
Dealing With a Car That Won't Start
Resources on Starting System Faults
Car starter problems? Don't blame the starter motor yet. These 5 troubleshooting tips will help you find the culprit.
Testing the voltage drop can help you find trouble spots in your starter circuit before you swap components unnecessarily.Resources on Charging Circuit Faults
Diagnose alternator and charging system problems with this practical guide to get your car back on the road faster.
Voltage-drop test your charging system circuit before condemning your alternator.Resources on the Fuel System
Learn how to test a fuel pressure regulator to save money and time in car repairs.Resources for Dealing with the Crankshaft and Camshaft Sensors
Troubleshoot an inductive or Hall effect type crankshaft position (CKP) sensor using a digital multimeter.
You can do a camshaft position sensor test using a digital multimeter at home and, if necessary, using a few common tools.
If your car’s ignition system has no spark, a few simple tests can help you locate the fault.Resources for Dealing With Battery Faults
This guide will show you how to use a digital multimeter, hydrometer, and other simple tools to troubleshoot, inspect, and clean your battery if necessary.
Find that parasitic battery drain that's causing your car battery problems whether you have a newer or older vehicle model.
