I have replaced the fuel pump and filter and all 4 plugs are getting spark what else could it be
Have you verified that there is fuel pressure?
If there is fuel pressure then you need to make sure the injectors are pulsing and that the timing belt has not broken.
The latter may be noticeable due to the engine cranking over abnormally fast.
Last question. Does the engine start and die, start and die, etc?
Have you tried spraying some starter fluid into the air intake of the throttle body and see if the engine starts and runs briefly, then stalls? If not, that’s probably the next step in the diagnosis. After that, probably a fuel pressure test at the fuel rail. Another idea, if your car uses a fuel pressure regulator, check to to make sure the vacuum line from it that goes to the intake manifold is completely dry, no gas in it on either end.
timing belt is good and we tried either
how do you check if the injectors are pulsing
when the engine cranks it acts like it wants to start but wont catch
Injector pulse can be tested with a Noid light or by using a stethoscope on the injectors while someone cranks the engine over. The light should pulse or one should hear clicking with a stethoscope.
What about the ignition switch. This model should be under a Recall for the switch which can cause a no-start condition or intermittent stalling. Switches are a common problem and not just on the Hondas covered under a Recall.
If starter fluid didn’t at least get the engine to pop and run briefly, most likely is you still have some kind of ignition system problem. Spark incorrectly timed or weak spark maybe. Describe the test method you’ve used to determine all four plugs are sparking maybe.
Poor compression could cause this. Did something significant happen just prior to the engine not starting problem?
I doubt this is caused by an injector problem based on the starter fluid test.
we pulled the spark plug wires and put them on a screwdriver then cranked it i could see the spark jumping to the metal from inside the car
how would i find out for sure and go about getting a new switch as we experianced the stalling before it shut off on a highway
So the car was running more or less fine for some time, then it stalled out for apparently no reason, and you towed it home and haven’t been able to start it since? One idea, you ran out of gas, and your fuel gauge isn’t working so you don’t know it. Pour a couple gallons of gas in the tank and see what happens.
half a tank of gas we added some and could see the gas when we replaced the fuel pump
just checked and the specific crv we have is affected by the ignition recall im going to get in touch with a dealer tomarrow to see about the replacment switch
Just curious but if you got spark at the plugs while running the starter motor, doesn’t that rule out the ignition switch? How would you get spark if the switch was faulty? Is the fuel pump actually turning on? The computer controls that. Is pressure correct? If using starter fluid was valid, how do you rule out the timing being off?
There might be multiple contacts inside the ignition switch, and the contact that closes to power-up the spark generating system is working, but maybe the contact for something else that’s needed for the car to start, like the fuel injection system, isn’t. That wouldn’t apply to my earlier model Corolla, the same switch contact is used for both on that car, but on a 98 CRV, maybe that’s the way it’s configured. A possible explanation anyway.
I’ve never tried this myself, but it should be possible to get an idea if the injectors are being pulsed just using an inexpensive volt meter. I can think of two methods, but the easiest would be to set the volt meter to measure AC volts, starting on like the 10 volt-AC scale. If the injectors are pulsing, you should get a measurable AC signal on one of the wires going to the injector connector. Back probe the connector pin, so it remains connected to the injector. You might need to rig up some type of thin-needle lead to get access for back-probing. Connect the other volt meter lead on a chassis ground. Then you’re set up for measuring for AC signals on the injector pulse pin.
If the injectors aren’t pulsing you should read 0 volts-AC instead. So as a test, a sort of baseline, you could just turn the key to “on”, and verify you read 0 volts-ac when back-probing , b/c the injectors aren’t pulsing with the key in “on” but the engine not started. Then crank the engine and see if you now are measuring an AC signal.
For testing spark, what I usually do is use a spare spark plug and connect it to a spark plug lead, leaving the other leads connected. Then crank the engine while holding the metal part of the spark plug against a chassis or engine ground. You should see a clearly visible whitish to blue spark jump between the electrodes. Reddish, no good.
AC? Doesn’t the car run on DC voltage? The alternator produces A/C current but it is immediately converted by rectifiers into D/C.
My point about asking whether or not the engine would start and die, start and die is precisely because of the switch.
It may be producing a spark while the switch is in the START position but when the key is released to the RUN position that spark may go away due to the switch internals having failed.
It would be easy enough to check with a test light. The red/white wire at the main relay is the one with constant power through the switch from my very fuzzy memory.
A test light is a better check than a voltmeter as it will apply more of a load to that circuit.
It wouldn’t hurt to check ALL fuses. There are roughly half a dozen or so tied to the switch and PCM.
Yes, the car is electrically powered by DC. But circuits within the car use switches to make and break the electric circuit, and that produces an AC signal. It’s like when you turn the headlights on, they stay on. That’s DC. But if you flipped the switch on and off every second, the lights would go on and off in a repeating fashion. That’s AC.
In the case of the fuel injectors, the switch that controls them is a transistor which turns the battery current on and off by the engine computer depending on the engine’s fuel needs. No need to guess. Try the experiment yourself on your own car. I expect you’ll measure an AC voltage on at least one of the injector pins when the engine is running. And no AC voltage when the engine isn’t running.
Not really, since the voltage never changes polarity.
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The AC volt meter has a capacitor inside that blocks the DC component. So even though it wasn’t, the meter would measure it like it was switching polarity. This is a common technique to test the alternator output too, to make sure the alternator isn’t producing a lot of AC, which can confuse computer circuits.
I’ve had that happen before, on my truck. The hot wire to the coil was working in the “start” position, but when the key is returned to “on” a different wire with a resistor in it is switched in to power the coil instead. And that resistor wire failed. So the engine would start up ok, but die as soon as I returned the key to “on”.