Can a bad fuel pump cause a jeep to not start?
A bad fuel pump, that has stopped sending fuel to the fuel injectors, will cause a ‘cranks but does not start condition’ on your 4.0L equipped Jeep. A fuel pump that is working, but not sending enough volume and therefore not producing enough fuel pressure, will cause severe drive-ability issues.
How to troubleshoot a no start Jeep 4.0L?
More specifically, this means that troubleshooting the problem requires that you check and confirm that: All 6 cylinders are getting spark (with a spark tester). That the fuel pump is creating enough fuel pressure. And if necessary, check the engine’s health with a compression test. I’ll go into more specific details in the following headings: 1.)
What happens when the fuel pump is low?
The PCM will still pulse (activate) all 6 fuel injectors. But when the fuel pump sends a lower than normal volume of fuel, your Jeep will start and run but with engine performance problems. You’ll probably see one or more of the following symptoms: Rough idle. Engine starts after extended cranking.
Why does my Jeep turn over but does not start?
Cranks But Does Not Start Condition: In this type of condition, you turn the key and the engine in your Jeep cranks (turns over) but it doesn’t start (run). The usual suspects, that can cause this type of problem, are a bad fuel pump, bad crank sensor, bad ignition coil (if your Jeep is distributor equipped), etc.
More specifically, this means that troubleshooting the problem requires that you check and confirm that: All 6 cylinders are getting spark (with a spark tester). That the fuel pump is creating enough fuel pressure. And if necessary, check the engine’s health with a compression test. I’ll go into more specific details in the following headings: 1.)
Cranks But Does Not Start Condition: In this type of condition, you turn the key and the engine in your Jeep cranks (turns over) but it doesn’t start (run). The usual suspects, that can cause this type of problem, are a bad fuel pump, bad crank sensor, bad ignition coil (if your Jeep is distributor equipped), etc.
What is the ignition system on a jeep?
The ignition system is the one tasked with creating and delivering spark to each of the 6 cylinders. Without spark, the engine will crank but Not Start. The ignition system of the Jeep vehicles covered by this tutorial use either a distributor type system or a COP (Coil-on-Plug) ignition coil system.
A bad fuel pump, that has stopped sending fuel to the fuel injectors, will cause a ‘cranks but does not start condition’ on your 4.0L equipped Jeep. A fuel pump that is working, but not sending enough volume and therefore not producing enough fuel pressure, will cause severe drive-ability issues.
Can a low pressure fuel system cause spark plugs to wear out?
A low-pressure fuel system will destroy the spark plugs that ignite the fuel in an engine’s cylinder. If by chance you are replacing them and you find they are worn out before their time, you might be looking at a problem with your fuel system.
What are the symptoms of a bad fuel pump?
Symptoms Of A Bad Fuel Pump. TEST 1: Using Starting Fluid To Confirm Lack of Fuel. TEST 2: Checking Fuel Pressure With A Fuel Pressure Gauge. Where To Buy A Fuel Pressure Test Gauge. Where To Buy The Fuel Pump And Save.
What should the fuel pressure be on a Jeep Cherokee?
The fuel pressure specification, from the Jeep repair manual, is 30 to 35 PSI. The only way this specification can be checked is by using a fuel pressure gauge.