i have a 94 honda civic 1.6L vtec and it wont let me rev above 2k and when i rev it a 2k it goes up and down. help

 

Check the cam timing, timing belt may have skipped. Most other reasons for that situation will throw a code. Is the CEL on?

 

yes it is throwing the codes 41, 7, 8

 

it is throwing these cel codes 7,8,41,14 i've already changed the tps and cleaned and switched out iac valve.

 

Code 8 is probably a bad distributor and that's why it won't rev right. Test the TPS with a voltmeter. When you replace it you must calibrate it so the throttle closed voltage is 0.4 volts. Make sure the plugs for the TPS and MAP have not been plugged to the wrong place. The one with a solid white wire goes on the MAP.

 

i fixed tps but still have codes 41 and 8 could it be the timing belt off one tooth

 

Code 8 is a timing pulse from the distributor, that is why it won't rev right. You need to fix that. The timing belt will not cause distributor codes.

 

After i fixed the tps sensor it now revs up and down so if i change the distributor out it should fix that too.

 

put different distributor on now its just throwing codes 41 and 14. Its idling real low and will cut off now. I cleaned iac could it be the o2 sensor doing it.

 

Be sure the timing is set properly. Adjust the air screw on the top of the throttle body so engine will keep running at 450-500 rpm with IACV unplugged. Then a normal idle should resume when you plug it back in.

If IACV plugged / unplugged seems to have no effect, check continuity of IACV coil (I think 40 ohms). Make sure that harness plugs for IACV and canister purge solenoid are not swapped.