I have a 1999 5-speed ford escort zx2, while im driving my rpm will jump up and down all the way to 0 and stay at 0 for a second and jump back up and down, .

The picture is for a zetec. Let me know if wrong diagram?

Top off ATF and re-test.

When you put in N - netural can you get full range of rpm?

The 1999 and 2000 model years of the Ford Escort offered a limited performance edition ZX2 S/R which further enhanced the cars performance in every aspect. The 1999 has been tested as going from 0 to 60 in 7.6 seconds.
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it could be down to your spark plug leads take the leads out one by one and get somebody to hold the lead to the engine [to earth it] NOT WITH YOUR HAND with something thats not conductive like something plastic then try starting the engine to see if a spark jumps from the lead and repeat this please dont do this with your hand its very dangerous enouf voltage to knock you out!

go get it checked at a auto parts store most of them have obd2 code readers that they can check it with there is a reason that light is coming on

Lost track of the number of turns on the tie rods so from 0-to what? how many turns dose it take to put it back to factory toe

If you have an RPM gauge take note when idling if the needle fluxuates up and down. If so a spark plug and or a plug wire is at fault

This is a common problem for a crankshaft sensor failure. When it fails, the engine can not start since the ECM doesn't know the proper position of the crankshaft to give ignition according to TDC (top dead Center). Therefore it doesn't matter how strong your battery is, it won't fire. The fire is only happens when an ignition happens at the highest compression point when a piston is at top and this is reported by the crankshaft sensor. Have this checked out and replaced. Good luck.

check for spark.if there is not one.Change the crankshaft senser After checking timming belt.

buy a new battery