Runs well in open-loop, but bad in closed
#1
Runs well in open-loop, but bad in closed
I have an 1985 Camaro 2.8L, manual trans. Basically when it is first started, running in open-loop the car runs really well. As soon as it heats up and goes into closed-loop, it bogs and has hardly any pickup. I have changed the following parts so far: throttle position, O2 and MAF sensors, Ignition Coil and module, cap, rotor, EGR Valve. All vacume lines have been fixed of leaks. I checked for codes and got code 32, 42, and 45. Not sure where to start diagnosing this problem. Last time I brought it to the shop, the mechanic mentioned something about high pressure in the gas lines. Any help figuring this problem out would be much apreciated!
Thanks Joe
Thanks Joe
#2
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Car: 2003 Hyundai Tiburon GT
Engine: 2.7L V6
Transmission: 6-speed
Axle/Gears: 4.41
Re: Runs well in open-loop, but bad in closed
Code 32 is an EGR failure, code 42 is a spark control failure or the set timing connector is disconnected, code 45 means you're running rich. Have you checked or replaced or done anything with the CTS?
Get a fuel pressure gauge to test the fuel pressure yourself... The return side of the fuel system may need to be blown clean from the FPR to the fuel tank...
Get a fuel pressure gauge to test the fuel pressure yourself... The return side of the fuel system may need to be blown clean from the FPR to the fuel tank...
#3
Re: Runs well in open-loop, but bad in closed
Yea i didn't know which code to start looking at. By CTS do you mean coolant temperature sensor? if so, never did change that.
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Car: 2003 Hyundai Tiburon GT
Engine: 2.7L V6
Transmission: 6-speed
Axle/Gears: 4.41
Re: Runs well in open-loop, but bad in closed
Code 32 may be caused by a bad EGR solenoid or plugged/disconnected vacuum line leading to either the solenoid or the vacuum sensor, code 42 will pop up if the timing set connector by the blower motor (the fan for the heater, not the radiator) is disconnected, and code 45 could be caused by high fuel pressure or a CTS out of spec, or a bad MAF sensor. Test the CTS with a multimeter set to measure the resistance of the sensor on the 20K ohms scale.
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Car: 89 Camaro RS running MS2X
Engine: .48/.60AR T3/T4 2.8L V6
Transmission: Rebuilt 700R4 2500 stall
Axle/Gears: Next to break...
Re: Runs well in open-loop, but bad in closed
sorry to jack someone elses thread, but i figured since its relevent, instead of starting another ill post here. im also having the 32 and 42 code, i just replaced the egr valve and read somewhere that if the ports are clogged with carbon deposits it will also pop code 32. also for the code 42, my est connector is connected and there is a drop in rpms when disconnected. my idle feels like i have the ac compressor running, even when its not, most noticable in the 1000rpm range. any suggestions?
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Car: 1990 Camaro RS
Engine: LT1
Transmission: 4L60E
Axle/Gears: 10 bolt, 3.73 Ratio, Torsen LSD
Re: Runs well in open-loop, but bad in closed
Had a similar problem with my 90 RS 3.1.Ran good when cold but idle surged when it was warmed up. Ended up being the IAC. they didnt have the $80 one specific to thirdgens so i bought a fourthgen one. Iyt was less then half the price and has worked so far. The plug is forward facing instead of downwards like the stock one but the harness will reach.
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