As the title suggests, I have a 2003 Civic LX that will only start with starting fluid. Once started and runs fine and I am stumped as to why it will not start. Here is what I know:

1. There are no DTC codes stored

2. Fuel pump seems to be fine. You can hear the pump kick on for approximately 2 seconds and the car runs fine once running. I have cycled the key several times before attempting to start and it doesn't seem to help. I have not actually measured the fuel pressure but running even at highway speeds seems to suggest that the fuel pump is okay.

3. Spark plugs look good, nice tan color with no carbon buildup. The plugs are dry thus I do not believe the engine is flooded.

4. Crankshaft position sensor seems to be working as the engine speed when checked with a scan tool is steady and follows engine rpm.

5. I have not had the battery load tested, but the results were the same when I attempted to jump start the car with a battery that was known to be good.

6. Both STFT and LTFT levels look to be okay, around 3% or less.

7. Coolant sensor is working as I can see the temperature on the scan tool rise and then fall when the fans kick on.

8. Air intake temperature seemed to be a bit high on the scan tool. Ambient air temp was around 90. The temp on the scan tool read 111, with the engine running and the hood open.

Any suggestions?

 

fuel pump, if it starts with starting fluid then that means you are not getting the fuel. test fuel pressure, change your fuel filter and fuel pump and strainer.

 

Update:

Short story: It was the crankshaft position sensor.

Long story:
Opportunities to work on the car are few since this is my daughters car and she is off to college. Using the starter fluid has been getting her by until I could get it fixed.

The consensus from various sources seems to be the fuel pump but I still had my doubts as the car runs fine once it starts. To verify the fuel pressure I rented the fuel pressure gauge from Oreilly's only to discover that it does not have the correct adapters to tie in to the fuel system. Therefore I was going to make an appointment at a repair shop to get it checked. (My point being don't waste your time renting the gauge)

Then came the call last Thursday that she couldn't get the car to start even with starting fluid. So I load up the trailer and bring the car home. Repair shop is going to charge at least $50 just to test the fuel pressure and the pump costs $60 so I decided to install the fuel pump without testing it. Probably a good idea to replace it even if it doesn't fix the problem as the daughter has a history of running out of gas.

I pick up a fuel pump on the way home and once I get the car unloaded I notice that the MIL is on. Read the code and it is P0335, crankshaft position sensor. Finally, a diagnostic code I can work with. I go ahead and install the fuel pump, clear the code, and try starting the car. Acts like it occasionally wants to start but will not. My scan tool has a live data function so I bring up engine rpm and watch it while cranking the engine. Rpm's stayed at zero on the scan tool while cranking except when it tries to fire and the rpm's jump to around 400 for just a fraction of a second, yet the MIL never comes back on. It does seem to confirm an issue with the sensor.

Another trip to the parts store for a crankshaft position sensor, install it, and the engine fires right up. I can not explain why the car would start with starting fluid and then would run fine. A combination of fuel pump and crank position sensor? Possible I guess, seems unlikely though. Car is running and the daughter is back at school so I am thrilled.