So where to begin? I am trying to figure out what the issue with my 2000 V6 3.8L is.

edit: So just to add, I checked the fuel pressure at it is at 42 psi on the rail. From what I was reading I should be at 44 to 46 psi, not sure if that extra 2 psi would matter. (I am new to working on motors) I am honestly starting to wonder if my fuel pump might be going out.

Problem:
For a while now I will get what feels like missing when accelerating. At times while idling at a light I will have the same missing feeling which leads to bogging out and the vehicle dieing. I can usually turn the key and my car will start right back up. The other day my wife was driving and while she was cruising on the freeway, everything just cut off and she had to roll to a stop on the side of the road. She turned the key and nothing, almost like a dead battery. She got the car towed home and by the time I got home from work, the car started right up and still starts up. Right now it is having a sluggish start, but starts non the less. The entire time I have been having the missing issue I have not had a loss of fuel economy (at least a noticeable loss).

My attempt to diagnose and fix:
So I bought a OBD II reader and received a couple of codes which all lead to the O2 sensor on the driver side up stream. I replaced the O2 sensor along with all spark plugs and wires and cleared the codes. Problem still exist. No codes popped up for about a week and then the check engine light came on and I checked again.

I now have codes:
P0102: (MAF) mass airflow circuit low input
P1133: HO2S Insufficient Switching
P1514: Throttle Body Performance

I have taken the MAF sensor out and cleaned it with MAF spray, which seems to have done nothing. I was also told to check the IAC, and a course with my luck after doing a bunch of reading online, I come to find out that there was 1 year that Camaros had internal IACs and that is what I have.

So as of right now, I am looking at doing four things that I am hoping that will fix my issues.
-replace the MAF ( $98 at local parts store)
-replace the throttle body and MAF (around $300 for both)
-replace all the o2 sensors since the wiring looks fine ($279 for all 4)
-replace all of the above and be broke

Just looking to see if anyone might have any tips, suggestions, or advice that could help be figure out a solution that won't end up with my buying parts I don't need to buy or wasting time working on obsolete leads.

Thanks in advance for any information.

 

Also I forgot to add that when the car died on my wife the other day on the free way she noticed a dummy light she or I have never seen before. It was the Reduced Engine Power Light. Even when i checked the car out when I got home from work that day, I still have not seen that light.

 

Have you tried cleaning out the TB with throttle body/carb cleaner? I would also seafoam the car to get rid of any carbon deposits built up over there years both internally and in the fuel system. Did you re-scan it after after cleaning off the MAF sensor? The 02 sensors sound like their getting fouled or not giving the internal computer the correct oxygen level readings. Be sure no plug lines are crossed as well. I would also take a look at your cat, as they can give sensors faulty readings

 

When an O2 goes bad it throws everything out of wack and can even trigger MAF codes as well. For example, when my driver side upstream O2 went bad the car began to misfire and stall. I pulled 3 trouble codes:

P0300 - random misfire
P0133 - bank 1 O2 fault
P0174 - system too lean on bank 2 (usually an MAF fault)

I tested and replaced the defective O2 and all codes went away, the car has been running strong ever since.

There's an easy way you can test your O2 sensors using a propane torch and a multimeter. An oxygen sensor should generate 9/10 of a volt when fully heated. Light the torch and set the meter to read DC voltage up to 20 volts. Heated O2s should have 4 wires: 1 ground, 1 power for the heating element, + for the O2 circuit, and - for the O2 circuit.

Most replacement Bosch sensors:
Grey, Black (this is +), White, White
OEM sensors:
Tan, Purple (this is +), Black, Black

Attach one multimeter lead to the + O2 wire and the other to the casing of the sensor (for ground). This should read 0. Then hold the sensor's tip over the lit propane torch for 30 seconds while watching the multimeter (the very top of the fluted sensor should be in the center of the large flame). There should be rapid change in the readings if your sensor is healthy and it should peak around 0.9 (my cheap multimeter isn't very accurate so it peaked at ~0.8 for both old sensors I had lying around and a replacement Bosch from Pep Boys I tested which is totally acceptable)

 

Check your parts before you go on an expensive witch hunt and replace everything but the source of your problem.

 

Right on, thanks guys. I have not cleaned the throttle body yet. I should have tried that sooner. So I will clean it out today and see if it helps at all.

Catmaigne: I'll give that a try to all 4 of the O2 sensors to see if that can help figure out if a bad sensor is throwing everything off. Thanks

 

Only test the precat/upstream sensors. The 2 downstream sensors shouldn't have an effect on your A/F mixture, they're only there to check the functionality of your converters

 

gotcha, thanks again.

 

I haven't had a chance to jack up the car and do the O2 sensor test yet, but today I had some free time to pull the throttle body off and clean it out. First time in 146K miles that it has probably been cleaned. I made sure to get all of the old gasket of and replace it with a new one that surprisingly enough was made in the US . And of course I made sure that the butterfly's edges were cleaned up.
Sorry I didn't take after photos.





Made in the US

 

added edit to first post