Need help with my 2006 Pontiac g5 pursuit!!

sc123

New member
Joined
Sep 13, 2020
Messages
22
Reaction score
0
Points
1
It has 3 codes: P0301 (Cylinder 1 Misfire), P0446 (Evaporative Emission Vent System Performance), and P1174 (Fuel Trim Cylinder Balance). I’ve changed the coil spark plugs, replaced #1 coil. I’ve done 2 sea foam treatments. Idk what it could be. I don’t smell gas so I don’t think it’s a gas leak. It has a rough idle when it’s in neutral, like a sputtering sound almost (not backfiring), and it has a slight hesitation fuel injectors? I have no idea. The photo I attached under the “misfiring engine” title explains perfectly what my car is experiencing.
 

Attachments

  • 1629B3A8-4041-467A-938A-BB1A19100C05.png
    1629B3A8-4041-467A-938A-BB1A19100C05.png
    568.4 KB · Views: 3

sc123

New member
Joined
Sep 13, 2020
Messages
22
Reaction score
0
Points
1
-Faulty spark plug or wire (changed all 4 coil spark plugs, which resulted in more power but still have hesitation) ✅
-Faulty coil (pack) Changed #1 coil ✅
-Faulty oxygen sensor(s) (how do I check for this?)
-Faulty fuel injector (how do I tell if a fuel injector is damaged, I know where the fuel rail is located, but visually, how can I diagnose this possible problem?)
-Burned exhaust valve (How do I diagnose this)
-Running out of fuel (What does this mean?, is it referring to poor fuel mileage? If so, I don’t have this symptom).
-Poor compression (How would I do a test for this?)
Thx for your time!🙂
 

melsg5

Staff member
SUSTAINING MEMBER
Joined
Dec 8, 2008
Messages
22,998
Reaction score
358
Points
83
The answers to your questions are easily found just by looking them up. Testing O2 sensors and compression tests are all out there.
Have you done a fuel pressure test?
______________________________
 

sc123

New member
Joined
Sep 13, 2020
Messages
22
Reaction score
0
Points
1
No I have not. I will do some research thanks again for your time🙂
 

sc123

New member
Joined
Sep 13, 2020
Messages
22
Reaction score
0
Points
1
So I did a compression test all the coils are good so that rules that out. Changed my gas cap the seal was bad. Any idea what it could be now? Checked all the vacuum hoses etc. The only problem I noticed was a very dirty air filter could that be cause for the code?
 

melsg5

Staff member
SUSTAINING MEMBER
Joined
Dec 8, 2008
Messages
22,998
Reaction score
358
Points
83
The air filter could cause the P1174.
What were the compressor readings?
 

sc123

New member
Joined
Sep 13, 2020
Messages
22
Reaction score
0
Points
1
Coil #1 (newest one I’ve changed): 130, and the other 3 coils were 120.
______________________________
 

sc123

New member
Joined
Sep 13, 2020
Messages
22
Reaction score
0
Points
1
Yes I followed that exact procedure with the compression tester. I have not replaced it yet but I am going to replace the air filter under the hood as well as the cabin filter. Do you think a fuel pump could cause a misfire ?
 

melsg5

Staff member
SUSTAINING MEMBER
Joined
Dec 8, 2008
Messages
22,998
Reaction score
358
Points
83
Not on 1 cylinder
I recommended the fuel pressure test for the P1174 but that was before you said anything about the air filter.
It is a stock air filter?
 

sc123

New member
Joined
Sep 13, 2020
Messages
22
Reaction score
0
Points
1
I’m not exactly sure, I’m guessing so. There was 2 owners before me, and I’ve had this car for 3 years I’m guessing they didn’t do regular maintenance. But I found some filters for my exact make/model, so I’m sure that will make a difference if I change both filters hey?
______________________________
 

melsg5

Staff member
SUSTAINING MEMBER
Joined
Dec 8, 2008
Messages
22,998
Reaction score
358
Points
83
The engine filter may effect the codes.
 

sc123

New member
Joined
Sep 13, 2020
Messages
22
Reaction score
0
Points
1
Ok I’ll be sure to do that. I really appreciate your time and getting back to me. You’ve help me sooo much! So thank you it means a lot!!!🙂🙂
 

sc123

New member
Joined
Sep 13, 2020
Messages
22
Reaction score
0
Points
1
Hi so my cars engine light is blinking it has done this twice... I did some research and that means that it is a serious problem and I shouldn’t drive it! It also says that could mean catalytic converter damage 🙁 is that true ? 😢 😭 I ordered new parts: 4 fuel injectors, fuel pump, cabin air filter & vent filter.
 
Last edited:

melsg5

Staff member
SUSTAINING MEMBER
Joined
Dec 8, 2008
Messages
22,998
Reaction score
358
Points
83
If you have an overly rich mixture due to a clogged air filter or other causes you can burn out the cat.
______________________________
 

sc123

New member
Joined
Sep 13, 2020
Messages
22
Reaction score
0
Points
1
Do you think it’s already burned out ? Or do you think it’s still safe because it’s only blinked twice so far
 

melsg5

Staff member
SUSTAINING MEMBER
Joined
Dec 8, 2008
Messages
22,998
Reaction score
358
Points
83
I would think so since you have no code related to the cat
 

sc123

New member
Joined
Sep 13, 2020
Messages
22
Reaction score
0
Points
1
Hi I changed both air filters, but the housing for the air filter a clip broke on it so it slightly doesn’t close properly... it’s the tiniest gap. Would this mess up my air to my engine?
 

melsg5

Staff member
SUSTAINING MEMBER
Joined
Dec 8, 2008
Messages
22,998
Reaction score
358
Points
83
If it sucks in unfiltered air, it's not great.
 
Top