1994 GT. 347 C.U. short block. TFS top end. 75mm TB. Pro-M. 36lb injectors. Bassani Shorties. Accel ignition. Custom Tune. All emissions equipment is INTACT.
The car starts up and the idle can be a little shaky at first. If I let it run for 2 minutes or so it runs fine. If I move before that it will tend to stall. I can let the car idle for an hour with out a CEL. Within a half mile of driving the CEL comes on and stays on. Once it is warmed up in any gear if I try to drive along less than about 1300 rpm it tends to buck.
It has passed Ct emissions in the past. I need to go through Ct. emissions again but I have the following codes:
511- (Custom chip)
332- insufficient EGR flow
558- EGR vacuum regulator solenoid circuit failure
What I have done so far:
Replaced:
EGR valve
EGR position sensor
EGR vacuum regulator
Looked for vacuum leaks using smoke generator(found none)
Used a vacuum pump to verify EGR valvemoves (it does)
Just got back from the local Ford dealership. They verified codes but were unable to troubleshoot any farther because of the custom chip (?!?) Luckily they didn't charge me anything.
Looking for some ideas. I had the volt meter out looking to see if I could verify that the EGR position sensorwas seeing the valve move. When I checked the reference voltage I kept getting 6 Volts. That didn't make sense because I believe all the sensors in the engine compartment get a 5 Volt reference signal. I kind of stopped after that.
Could a fault in the EEC be providing the wrong reference voltage to my sensors?
I forgot to mention that the Ford technicianwho looked at the car suggested I consider replacing the TPS. In his experience a bad TPS could cause the drivability issues I am seeing. Not sure how that relates to EGR issues unless it is getting a 6 volt reference as well.
Looking for ideas where to look next. Not sure how to fix this.
Thanks
Nick K
The car starts up and the idle can be a little shaky at first. If I let it run for 2 minutes or so it runs fine. If I move before that it will tend to stall. I can let the car idle for an hour with out a CEL. Within a half mile of driving the CEL comes on and stays on. Once it is warmed up in any gear if I try to drive along less than about 1300 rpm it tends to buck.
It has passed Ct emissions in the past. I need to go through Ct. emissions again but I have the following codes:
511- (Custom chip)
332- insufficient EGR flow
558- EGR vacuum regulator solenoid circuit failure
What I have done so far:
Replaced:
EGR valve
EGR position sensor
EGR vacuum regulator
Looked for vacuum leaks using smoke generator(found none)
Used a vacuum pump to verify EGR valvemoves (it does)
Just got back from the local Ford dealership. They verified codes but were unable to troubleshoot any farther because of the custom chip (?!?) Luckily they didn't charge me anything.
Looking for some ideas. I had the volt meter out looking to see if I could verify that the EGR position sensorwas seeing the valve move. When I checked the reference voltage I kept getting 6 Volts. That didn't make sense because I believe all the sensors in the engine compartment get a 5 Volt reference signal. I kind of stopped after that.
Could a fault in the EEC be providing the wrong reference voltage to my sensors?
I forgot to mention that the Ford technicianwho looked at the car suggested I consider replacing the TPS. In his experience a bad TPS could cause the drivability issues I am seeing. Not sure how that relates to EGR issues unless it is getting a 6 volt reference as well.
Looking for ideas where to look next. Not sure how to fix this.
Thanks
Nick K