I have a 2003 civic Honda .engine cranking but wont start.Fuel and Ignition were check already no problem was found. Is it maybe because I have change the original alarm of my car to a new alarm? Do I need reprogram my car? Your good advice is highly appreciated

not told does engine crank fast. keyed to crank.????
yes / no . if not say that first.
the starter motor in a car is the best battery tester there is. so is starter dead./????????????
the IMMO on 90%of cars cuts fuel dead onlyl.
on the 10% it cuts starter and fuel both dead
many allow engine to run for 1 to10 seconds and stalls
the IMMo can not be hacked, and is its A#1 top designed purpose to do that, to stop thieves dead.
and works. all new cars have it and is mostly now mandated by laws.
this car I think cranks if key is bad. but will not start

all cars came with it new 2 new keys,working
lost the 2nd.?
we spend a huge amount of time here reading users guides to people lost. the manual is free to read.
at any time , im reading yours now google found it is 1second flat and 1st hit.
my posts are for USA cars only, nothing else ever.
unless they beg, LOL
the immo lamp is in the hot cold, fuel gauge port
if the IP cluster
i see a KEY icon there.it says read page 67
so I do.

"This indicator comes on for a few
seconds when you turn the ignition
switch ON (II). It will then go off if
you have inserted a properly-coded
ignition key. If it is not a properly-
coded key, the indicator will blink
and the engine will not start (see
page 81"
shows 2 immo keys and 1 valet key new

"If an improperly- coded key (or other device) is used,
the engine's fuel system is disabled
When you turn the ignition switch to
ON (II), the Immobilizer System
indicator should come on for a few
seconds, then go out. If the indicator
starts to blink, it means the system
does not recognize the coding of the
key. Turn the ignition switch to
LOCK (0), remove the key, reinsert
it, and turn the switch to ON (II)
again."

do not have other immo keys near the ignition switch
just 1 honda immo only, not even other cars IMMO keys.near, (as the manual said) and is true.
or the keys go to a loggerheads war (radio signals clash)

free guide

https://www.manualslib.com/manual/832826/Honda-2003-Civic.html?page=81#manual

https://can-i-do-it-myself.000webhostapp.com/Starting.html

check cranking compression also is ther gas on the spark plugs after cranking the motor say 20 seconds no gas then suck some gas into a 2 foot peice of vacuum line blow this gas into the manifold throttle(a spoonful) then crank if it starts then maybe bad fuel pump check to see if fuel is at fuel rail when the motor is cranking got gas? got spark ?are plugs blak and sooty ?(repleace) then check compression if its low by 20 to 30 pounds or has nun its jumped time at the timing belt/chain ask about that at auto zone and the ramifications

Do you check the engine system already?
Maybe the system got fault codes.
Use obd2 code scanner to check first. Make sure the fault code has been erased.

Are you saying the engine is difficult to crank, or start ?
If it cranks ok but takes a long time to start, the starter is not the problem. You would look at ignition or fuel.

Won't turn over? Do you mean the starter won't crank the engine over?

Or the engine cranks over and won't start, and you have tested for spark when cranking and have no spark? And then you have tested the coil and ignition module, and they tested out good? Am I on the right page here? If so, maybe the next thing to check would be the crank position sensor. The ecu (computer) signals the ignitor (ignition module) when to initiate spark after it digests the signals from the crank position sensor and the cam position sensor.

Most common problem when this happens is the ignition module,complete distributors are available at low cost because of this common problem.Do you have spark?

does it crank, is it getting fuel, how about ignition timing is it correct then you have cam timing, remember the principles to check a engine, **** start bang blow.....

Make sure your distruibutor rotor in turning while cranking engine, if it is timing belt ok, more then likely your not getting spark to spark plugs check your ignition coil, but more then likely it's going to be your ignition module.

An engine needs 3 things to run: Fuel, compression, ignition.

Maybe the timing belt went out. Take off the dist cap and see if the rotor turns as you crank the engine.

Next run a compression test on all the cylinders.