So I have a fully Built d16y8 and I cant get it to idle properly. The timing is dead on but I never degreed in my comp cam its set at oem specs. Can that cause it to not idle correct?..but then again Im throwing a check engine light for an o2 sensor but its turbo so I dont have a o2 I just got my wideband. If thats not tuned outta the ecu in my basemap will it cause it to run like that?
Im seriously lost on this one guys I need some info… I can get the car to run if im giving it gas but as soon as I let off it dies.
Ill be stoppin back many times tonight on this thread so feel free to leave your .02 here. Thanks!
It may be the idle air control motor. An IAC (idle air control) motor is designed to adjust the engine idle RPM speed by opening and closing an air bypass passage inside the throttle body. The cars computer or ECM (electronic control module) receives information from various sensors and will output signals to adjust the IAC motor in or out to adjust engine idle speed by controlling engine idle air. An IAC motor can fail one of two ways, either the motor short circuits and stops working or the motor will develop high resistance and cause the IAC control motor to react slowly, either failure can cause the engine to stall at idle. When a trouble code scan is performed it sometimes won’t always detect a failed or weak IAC motor. To check the IAC motor remove the unit, with the wires connected turn the key to the “on” position without starting the engine, the IAC should move in or out. If the IAC motor does nothing it has probably failed, replace it with a new unit and recheck system. Note: while the IAC motor is removed clean (use aerosol carburetor cleaner) the passages the IAC uses to control idle air speed, also inspect the IAC for a build-up on the seating (pointed) end and clean as necessary. I hope this helps
Hope this helps
Common Problems
An IAC motor is highly susceptible to carbon and coking build up; if an IAC goes too long without cleaning it can cause stalling and poor idle quality. Some cars are designed with a large vacuum transfer hose that connects the intake manifold to the IAC (idle air control) motor. If a broken or dilapidated these vacuum lines can cause the engine to lose vacuum which will allow the engine to run rough and die. Inspect all engine and accessory vacuum lines to look for missing, torn or dilapidated lines and replace as needed. Any car that is designed with a magnetic non-motor operated IAC like Toyota/Lexus is subject to carbon and should be cleaned about every 40,000 miles to avoid stalling.
Basic Maintenance
To check the IAC motor remove the unit, with the wires connected turn the key to the “on” position without starting the engine, the IAC should move in or out. If the IAC motor does nothing it has probably failed, replace it with a new unit and recheck system. Note: while the IAC motor is removed clean (use aerosol carburetor cleaner) the passages the IAC uses to control idle air speed, also inspect the IAC for a build-up on the seating (pointed) end and clean as necessary.
it’s not iac, if your basemap is throwing code for o2 it’s not disabled and your car is looking for it to run/idle. With it not being there, it will barely run, or run very poorly unless you are WOT.
not true, the car will just run in closed loop and revert to settings. WHat wasnt mentioned is that the car barely runs when he is on the gas. It chuggs unless something has changed since the last time i saw it.
when I fired my built A20A, the engine barely wanted to run, it would idle for a few seconds then stumble and die. Then, when it was idling, if you blip the throttle just very slightly it would die, and every time you reved the engine up, as the rps came down, it would die. For me, long story short, it was the tune. I needed to add fuel everywhere because the LARGE precision injectors I have dont like to idle over 13.5:1 afr haha. I swapped basemaps to get the car to idle and then started to go from there tuning etc. The engine is a turbo motor and cammed too.