Hi
I'm new here and I need your help
I bought a honda prelude 2.2 vti 4ws (5gen)
few months ago and it was working perfectly
about a month ago she started jerking really bad when letting go of the gas pedal when driving
I've been to 3 different mechanics we changed the MAP sensor,IACV,throttle position sensor and checked all the vacuums and its still the same
On the tester at the mechanic it showed
P1508 IACV current
and it showed an error of the map sensor
but we changed everything even
do you think it could be a bad wire somewhere?
please help
thank u

 

Forgot to write that we checked the ECU and its fine

 

did you use oem parts or replacement?

replacement part sensors doesnt work that well....

 

Mechanic said that the distributor cap is okay and working fine

 

We used oem parts
used but they are as new

 

Before throwing any more sensors at it, you should check continuity to each wire in that portion of the harness, and move them around a bit on each end while testing, in case moving causes a short. I had a map wire grounding out and doing that, only found it when I pushed the carpet back down by the ecu wiring while the car was running.

 

Could be the IACV acting up, it could be damaged, especially if you have a fault code for it. It's a small 12v stepper motor connected to a valve and seat that the ecu uses to vary the amount of air entering the engine with the throttle closed to maintain and adjust idle.
If it for whatever reason starts adjusting and moving when you let off the throttle it will cause the engine to receive air that is not metered and will cause a lean burn condition or sparatic burn when your on decel with the throttle closed.
You can clean the valve if it has excessive carbon buildup and you can test the electronic portion of the valve with a multi-meter.
You can also replace the valve if it is faulty, I'm pretty sure the OEM Genuine Honda parts catalog still has it but if not there are several aftermarket companies that sell them, they average about $50