I figured I'd post this as a guide to help everyone else with a 5-6 gen monte carlo. There is a few repeat threads I'd like to help eliminate. Also some common problems I've come across with myself.
Feel free to post your problem fixes too. (pictures needed too!)
Problem: Hard start/ rough idle for first 5 seconds of start-up. Hesitation at idle.
Possible cause: Bad IAC(Idle Air Control) Valve/ Bad Fuel Pressure Regulator/Dirty MAF
How to test: Pull the Vacuum line off the fuel pressure regulator, if fuel is present in the line then replace FPR. Test pressure at the fuel pump, then at the rails for any fluctuation. |||| For IAC, take out the IAC valve & clean with light cleaners(MAF sensor cleaner works great) Pull & push the tip of the IAC & clean the shaft. Spray with WD-40 or other lubricants & push back in. Re-install with a little di-electric grease on gasket(not needed, but prevents air leaks) If problem goes away for a week or two(or see improvement in problem), your IAC is bad. |||| MAF problems, clean with MAF cleaner first. If MAF is truly bad, CEL will come on, severe lack of power & car may stall out at times. (temporary if MAF is bad) Unplug MAF sensor to see if idle evens out. Do not drive like this, it wastes ALOT of gas.
Majority of the time the IAC is bad. Just changed mine out & what a difference! Clean the MAF at the same time (just to be sure) and inspect air filter to make sure its not clogged. For safety, remove negative battery terminal to prevent shorting out the sensors.
Diagram of Throttle Body & location of Fuel pressure regulator (Supercharged 3.8 shown)
Spoiler
Problem: Security Light illuminated on dash board/ No crank start
Possible cause: PASSLOCK system has malfunctioned.
How to test: Some shop code readers can read the security light code, but once that light flashes its probably the passlock system.
How to fix: Replace keys & ignition cylinder. Needs to be re-programmed with a GM scanner OR! bypass it (click spoiler for how-to)
1. Take the side panel off the dash (one by the door on the end of the dash) remove the screw. 2. Remove the lower most panel on the drivers side foot well. watch the wires for the trunk release. 3. When you get that one, the next one just snaps out, pull up on it. 4. There is a screw in the end cap, the one in the glove compartment and one in the lower part of the dash by the gauge cluster you need to remove. 5. Now take your key off the key ring. (This is so it can go threw the dash with out breaking anything and also with out hurting the ingnition switch) Take the ignition switch ring off. It just clips in, use a small screwdriver to remove it. 6. Put your key in and set the parking brake. 7. Tilt the wheel all the way down. 8. Put the car in to low 1 gear with the car still off. Now grab the lower part of the dash on the passenger side with the glove box open and pull hard on the lower part of the dash but don’t let it go too far out . 9. Disconnect the hazard switch wires so that you can get the dash apart. (it should pop lose for you. Now it is just a matter of spinning it in the right direction to get it over the steering wheel etc... ) 10. Put the car in gear and turn off the switch.
Bypass the Passlock
1. Disconnect the Car Battery! 2. Remove the ignition keyswitch. Unscrew the two screws holding in the ignition. Wiggle the ignition out of its place and down toward the drivers side as best as you can (This will really take some effort to get it out so that you can access the wires behind it). I initially tried removing the radio to get behind the ignition switch but it is not possible due to a metal plate separating them. 3. (See Picture Below) There will be 3 wires in a black sheath coming out of the ignition. The wires are Black, Yellow, and White. You will need to cut back the black sheath to get to them. We will only be working with the Black and Yellow wires. 4. Cut the yellow wire. Leave enough coming out of the ignition that you can get to it later or reattach it if you ever want to. Leave enough coming from the car that you can solder to it. Strip back both ends of the yellow wire about 1/4". 5. DON'T CUT THE BLACK WIRE. Strip about 1/4" of the insulation off of the middle of the black wire. Do this in a place where you will be able to solder to it later. Again, use the razor. 6. Make sure that none of the bare wires are touching each other or bare metal and RECONNECT THE BATTERY. 7. Following the multimeter's instructions, connect one lead to the black wire. Connect the other lead to the half of the yellow wire that is attached to the ignition (not the half going to the car). It will be much easier if you have alligator clip leads for your meter. Insert your key and turn it to RUN but do not start the car. I did not get any reading at this point. Try to start the car. It should turn over and run for a second but then die. Read the value on the meter. I believe I was getting around 1.8k ohms. Your car will likely have a different value, so you have to measure it. 8. DISCONNECT THE BATTERY and the meter. Make sure the wires are not touching. 9. Use a combination of resistors to come up with a value as close to the value you read as possible. If you put the resistors in series just add the values for the total resistance. If you put them in parallel you will need to calculate it, if your using 2 resistors with the same value you can just divide that value by 2 for the total resistance. I believe I used two 3.6k ohm resistors in parallel (twist the ends together) to equal 1.8k ohms. Found this good online calculator for calculating resistors in parallel, http://www.1728.com/resistrs.htm 10. Use test leads (wires with alligator clamps on each end) to connect one end of the resistors to the black wire and the other end to the yellow wire that goes to the car (not the yellow wire to the ignition keyswitch). Make sure that none of the wires is touching another wire or bare metal. 11. Reconnect the battery and attempt to start the car. It should start normally. If it doesn't, I would guess that your resistors are not of the proper values. Mine started, so I didn't get into troubleshooting. 12. DISCONNECT THE BATTERY and the test leads. 13. Solder 2" or so of 20-22 gauge wire onto either end of your resistors. Make sure the joints are very secure. If a resistor or wire becomes disconnected YOUR CAR WILL NOT START. 14. Tape off the yellow wire coming from the ignition switch. This wire is no longer used. 15. (See Picture Below) Slide shrink tubing over the yellow wire coming from the car. Solder one of the wires attached to the resistors to the yellow wire coming from the car. Slide the shrink tube over the joint and shrink it. I used shrink tube but I know not everyone may have easy access to shrink tube and a heat gun, wrapping it up in electrical tape also works. 16. Solder the other wire that is attached to the resistors to the stripped area of the black wire. Using good quality electrical tape (3M), tape this joint so that it is insulated and so that the tape supports the solder joint. 17. Reconnect the battery and try to start the car. It should start. 18. Slide the anti friction sheath back down over the wires if possible. Otherwise you can use electrical tape to stand in for the sheath. Move the ignition switch back into place, positioning the new wires so that they don't touch anything that will cut them. Be careful you don’t accidently tug any of the wires you just soldered. 19. Screw the ignition switch back into place, put the dash back in, and you are finished!
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If you are ever stuck with the no-crank start, try wiggling the key in the 'start' position a few times until the car finally kicks over. It usually gets me going. Also, use the fob to lock & unlock the doors sometimes helps too.
Problem: musty/moldy smell in A/C / Heating system
Possible cause: dirty cabin filter
How to fix: located on passenger side, right under the plastic cowl under wiper. With hood up, remove the weatherstripping & pop rivets under wipers (helps if wipers are in the up position) remove the cover. Remove any dirt & leaves in area & take out cabin filter. Replace with a new one(most auto parts stores carry them) Re-assemble the same way you took it apart.
Diagram on how to remove cabin filter
Spoiler
Remove plastic washer fluid line first. Pull weatherstripping up to yellow arrow. Pop rivets arrowed in red. I don't have a screwdriver at the moment, but once the cover is off its easy.
