My battery is new. starter is new. the key has been checked. ignition switch on but does not start the engin. if you o underneath the car with a wire to bypass the sterter the feulpump dont come on

Neutral safety switch, clutch pedal switch, starter solenoid disconnected, ignition switch. Its a good idea to diagnose before replacing parts that are not working. Like a chain, a broken link causes the chain to not work

There is no starter relay shown in a wiring diagram. The only thing between the ignition switch and the starter solenoid is the park/neutral switch (or the clutch pedal position switch on manuals).

Do the warning lights and gauges come on with key on? That would verify power is into the switch and being sent out. The small purple wire on the starter solenoid should have power on it when the key is held in start position. If it does, recheck your starter and battery connections. When the purple wire energizes the solenoid, the starter motor should crank the engine.
If no power on the purple wire in start, check the neutral safety switch or the clutch switch if a manual. The start wire out of the ignition switch is a yellow wire, and the wire from either safety switch to the starter solenoid is a purple wire.
(The power to the ignition switch is from the 50 amp Ignition fuse in the under hood fuse block.) See? The positive battery cable is connected to the starter, but not to the starter motor. When the key is in start, the hot purple wire energizes the solenoid and the battery cable is connected to the starter motor.

What happens when you turn the key to on? Do the warning lights and gauges come on? Turning the key to start, do the lights and gauges stay on? Just nothing at the starter?

Or does power just shut off when you turn the key to start, everything goes out, no warning lights or gauges? Then check cables, battery terminals, grounds for clean tight connections. There is a problem between the battery and the ignition switch.

If the switch still receives and sends power out (to the dash, for one) but start circuit is not working (from battery to ignition switch to clutch switch to starter relay to starter solenoid to starter to ground-and back to battery), then here's where we at: with key off, use a small screwdriver and short the big cable at starter to the starter solenoid small wire connection, or use a small jumper wire to do the same-battery cable at starter to the small wire connection on the starter solenoid. Starter motor should spin and crank engine. Does it? If so, start checking the start wire out of ignition switch for power when key is held in start. If you have a clutch switch, check for power in with key in start. Should have battery voltage to the clutch switch with key held in start. Keep checking the start wire along the start circuit. Not sure how the start relay is wired into the circuit, would have to see a diagram, but if you pull the relay out and use a test light or multi meter, could check for power on the terminals where relay plugs in. Key off, should have one terminal that is hot. With key held in start, at least one other terminal should also be hot. This would be the start wire out of ignition switch sending a signal to the relay.
Good luck, hope you find it. Sorry I don't have a wiring diagram to help you more.

Hi, diagnosing a no-start condition requires a logical approach to figuring out what might be preventing your car from starting. First, if the engine won't even crank over when you turn the ignition to START, your car obviously won't start.
When you turn the ignition key to start your car, voltage from the battery flows through the ignition switch to the Park/Neutral safety switch and/or brake pedal or clutch pedal safety switch (you have to push the pedal down before the circuit will complete) to the starter relay or solenoid. When the relay or solenoid is energized by voltage from the ignition switch circuit, it closes a contact that routes more power from the battery directly to the starter to crank the engine. The starter motor spins, pushes the starter drive gear to engage the flywheel and cranks the engine.

If the engine fails to crank, there is a fault in one of the components in the battery/ignition/starter circuit.

Ten Reasons why you car won't start..

1. Low battery (Check battery voltage, recharge if low, or jump start with another vehicle or battery charger).
2. Loose or corroded battery cables (Inspect, clean and tighten BOTH ends of BOTH battery cables).
3. Bad starter relay wiring connections or ground connection (Inspect, clean, tighten wiring connections).
4. Bad starter relay/solenoid (Check for voltage at relay, if relay has voltage but there is no "click" when key is turned to start, replace relay).
5. Bad starter (Jump battery voltage direct to starter to see if it spins, or remove starter and have it bench tested at auto parts store).
6. Damaged starter drive or teeth on flywheel (Remove starter and inspect drive gear and flywheel teeth, replace damaged parts if necessary).
7. Bad ignition switch (Check to see if voltage reaches starter relay/solenoid when turn to start. If not, check for open P/N switch and brake or clutch pedal switch. Replace ignition switch if defective).
8. Open P/N safety switch, or open Brake Pedal Safety Switch (automatic transmission) or open Clutch Pedal Switch (manual transmission). Bypass switch with jumper wire to see if engine cranks, or use test light or voltmeter to check for voltage passing through switch when ignition is turned to start.
9. Engine seized due to bearing failure or internal damage (Use socket and long handle to see if engine can be turned by hand, if not engine is locked up).
10. Engine hydrolocked due to coolant leak from leaky head gasket (Use socket and wrench to see if engine rotates, remove spark plugs and see if coolant comes out or engine can not be cranked with plugs out).

Hope it helps identify and solve the problem

Hi, this is what you should do when your car won't start. Diagnosing a no-start condition requires a logical approach to figuring out what might be preventing your car from starting. First, if the engine won't even crank over when you turn the ignition to START, your car obviously won't start.
When you turn the ignition key to start your car, voltage from the battery flows through the ignition switch to the Park/Neutral safety switch and/or brake pedal or clutch pedal safety switch (you have to push the pedal down before the circuit will complete) to the starter relay or solenoid. When the relay or solenoid is energized by voltage from the ignition switch circuit, it closes a contact that routes more power from the battery directly to the starter to crank the engine. The starter motor spins, pushes the starter drive gear to engage the flywheel and cranks the engine.

If the engine fails to crank, there is a fault in one of the components in the battery/ignition/starter circuit. Check it out.....

• Low battery (Check battery voltage, recharge if low, or jump start with another vehicle or battery charger).
• Loose or corroded battery cables (Inspect, clean and tighten BOTH ends of BOTH battery cables).
• Bad starter relay wiring connections or ground connection (Inspect, clean, tighten wiring connections).
• Bad starter relay/solenoid (Check for voltage at relay, if relay has voltage but there is no "click" when key is turned to start, replace relay).
• Bad starter (Jump battery voltage direct to starter to see if it spins, or remove starter and have it bench tested at auto parts store).
• Damaged starter drive or teeth on flywheel (Remove starter and inspect drive gear and flywheel teeth, replace damaged parts if necessary).
• Bad ignition switch (Check to see if voltage reaches starter relay/solenoid when turn to start. If not, check for open P/N switch and brake or clutch pedal switch. Replace ignition switch if defective).
• Open P/N safety switch, or open Brake Pedal Safety Switch (automatic transmission) or open Clutch Pedal Switch (manual transmission). Bypass switch with jumper wire to see if engine cranks, or use test light or voltmeter to check for voltage passing through switch when ignition is turned to start.
• Engine seized due to bearing failure or internal damage (Use socket and long handle to see if engine can be turned by hand, if not engine is locked up).
• Engine hydrolocked due to coolant leak from leaky head gasket (Use socket and wrench to see if engine rotates, remove spark plugs and see if coolant comes out or engine can not be cranked with plugs out).

When you turn the ignition key to start your car, voltage from the battery flows through the ignition switch to the Park/Neutral safety switch and/or brake pedal or clutch pedal safety switch (you have to push the pedal down before the circuit will complete) to the starter relay or solenoid. When the relay or solenoid is energized by voltage from the ignition switch circuit, it closes a contact that routes more power from the battery directly to the starter to crank the engine. The starter motor spins, pushes the starter drive gear to engage the flywheel and cranks the engine.

Low battery (Check battery voltage, recharge if low, or jump start with another vehicle or battery charger).
Loose or corroded battery cables (Inspect, clean and tighten BOTH ends of BOTH battery cables).
Bad starter relay wiring connections or ground connection (Inspect, clean, tighten wiring connections).
Bad starter relay/solenoid (Check for voltage at relay, if relay has voltage but there is no "click" when key is turned to start, replace relay).
Bad starter (Jump battery voltage direct to starter to see if it spins, or remove starter and have it bench tested at auto parts store).
Damaged starter drive or teeth on flywheel (Remove starter and inspect drive gear and flywheel teeth, replace damaged parts if necessary).
Bad ignition switch (Check to see if voltage reaches starter relay/solenoid when turn to start. If not, check for open P/N switch and brake or clutch pedal switch. Replace ignition switch if defective).
Open P/N safety switch, or open Brake Pedal Safety Switch (automatic transmission) or open Clutch Pedal Switch (manual transmission). Bypass switch with jumper wire to see if engine cranks, or use test light or voltmeter to check for voltage passing through switch when ignition is turned to start.
Engine seized due to bearing failure or internal damage (Use socket and long handle to see if engine can be turned by hand, if not engine is locked up).
Engine hydrolocked due to coolant leak from leaky head gasket (Use socket and wrench to see if engine rotates, remove spark plugs and see if coolant comes out or engine can not be cranked with plugs out).

Check voltage at starter, there's a big wire and a small one, the big wire should have voltage all the time, the small one will only have voltage when key is at start, with test light check voltage at big wire, if no voltage check battery terminal's, if there is voltage then check voltage at small wire while some one hold's ignition key to start if you have voltage bad starter, also hit starter while key is at start some time's it will crank engine over, but you'll need to replace starter, if no voltage check ignition switch, good luck, hope this was very helpful.

when the key is held in the start position do u have 12 volts to the starter solenoid? if you do have the 12 volt signal then I suspect the starter solenoid is bad, but I doubt that is the problem, it is more likely the actual ignition electrical switch that is actuated by the ignition lock cylinder, the switch is located just behind the key cylinder inside the steering column, to replace it you must remove the column trim covers the switch is attached to the back of the ignition lock cylinder Assembly. Base on what i have read this switch is a common problem. here is a picture.

Check and make sure you are getting power to the ignition switch and to the stator wire on the starter. Turn the key on and and measure the volts going to the starter on both wires. You should a atleast 12 volts going to the stator wire and to the main wire from the battery. If you are not getting power there it could be a fuseable link in the power wire from the ignition. I noticed that you replaced the ignition switch make sure the rod from the key switch has not come out of the switch.

You will have to check, at the starter, for power to the SMALL wire on the starter solenoid (which is on the starter) when turning the ignition switch to start.
If there is power to this wire ( usually purple ) and power at the LARGE cable ( from the battery ) at the starter end.....you need a starter.

If you do not have power at the small wire at the solenoid with the key in start position and battery power is OK.....check the safety neutral switch.Moving the shifter around a little can sometimes allow the car to start if the neutral switch is worn.

A new battery does not always mean a fully charged battery.
Try a boost from another car before testing the starter for power.

The battery cables need to be clean and tight....and check the ground to the engine as well.

Everything else may work OK with bad connections,they don't use the power the starter needs to turn the engine over.