wont idle

[beihl304]

sooo my car has been running great until today. i put in a chipped eprom ecu and went to start it up. when i started it up it ran great for a minute or so then out of no where my vacuum read about 9 and it sounded like my car had cams and it was idling at 500. i decided to drive it and it would run fine other than when i would come to a stop it would almost die and idle all crazy again. so then i reset the ecu and the car ran good and then did the same thing all over again. but now it will not start unless i hold the gas pedal to the floor then it starts but as soon as i let off the gas it dies again.

my question is that im a p0443 code which is the evap. could this really cause my car to not idle?

 

[Aproductions]

Evaporative Emission Control System Purge Control Valve Circuit
What does that mean?

The Evaporative Emissions System (EVAP) allows fumes from the gas tank to enter the engine to be burned, rather than vented into the atmosphere as an emission. The purge valve solenoid is supplied switched battery voltage. The ECM controls the valve by operating the ground circuit, opening the purge valve at specific times allowing these gasses to enter the engine. The ECM monitors the ground circuit as well, watching for faults. When the purge solenoid isn't activated, the ECM should see a high voltage on the ground circuit. When the solenoid is activated, the ECM should see the ground voltage pulled low, close to zero. If the ECM doesn't see these expected voltages, or senses an open in the circuit, this code is set.

Potential Symptoms

P0443 trouble code symptoms could be just an malfunction indicator lamp (MIL) illumination. There may be no drivability problems at all. But, it's also possible to have a lean condition or a rough running engine if the purge valve is stuck open. Usually though, these symptoms are accompanied by other EVAP codes. Another symptom may be excessive pressure in the gas tank in the form of a "whooshing" sound when the cap is removed, indicating a purge valve that isn't working at all or stuck closed.
Causes

To cause a P0443, there has to be a problem with the purge control CIRCUIT, not necessarily the valve. Usually they are a unit housing the valve and the solenoid as an assembly. Or it could be comprised of a separate solenoid with vacuum lines to a purge valve. That said, it could be any of the following:


This is what is wrong most likely, so check these out.

* Bad purge solenoid (internal short or open)
* Wiring harness chafing or rubbing another component causing short or open on control circuit
* Connector worn, broken or shorted due to water intrusion
* Driver circuit inside powertrain control module (PCM) is bad

 

[beihl304]

thanks for the reply but i have already read that. i wasnt sure if it was different on our cars because other people told me it wouldnt have any drivablility issues. i am guessing that it is stuck open? thats what says causing rough idle so how might i check this? thanks

i tried the stock chip with the eprom ecu and it still did the same thing. so then i put in my stock ecu and car ran great. so obviously it was the ecu