Mazda Repair: Engine hesitation,, mazda 626 lx, engine hesitation

Question
1999 Mazda 626 LX mileage: 110000. My Mazda 626 has the
following problem: when cold, no problems are apparent. Once at
normal operating temperature, it idles erratically and stumbles
during normal acceleration - the stumbling is similar to water in
the gas or misfiring. It operates well at a constant speed (say
highway speed). The "check engine light" has come on.

Answer
Hi Spyros thanks for asking.
I have seen this problem many times with theses 2.0 liter and 1.6 liter engines. the intake manifold gaskets are common for cracking and letting outside air get sucked into the intake manifold, with to much air the cylinder will not fire. the check engine light will either be a multiple cylinder misfire code or a specific misfire code--- 1,2,3 or 4, this is cause by this air leak  "vacuum leak"
Have someone qualified to inspect and test to see if it is leaking,
get back to me with the results.
good luck
Chris P