6th Gen ('00-'05): 2002 Monte Carlo SS Dale Earnheart 3.8
#21
12-01-2021, 10:31 PM
All injectors have same voltage when car is running. Aprox 8 volts. Engine off key on 5 volts
Now I just started car after erasing codes earlier and car ran very good then idle went from 800 to 1100 and check engine light came on it threw the PO304 again but no CTS code
Very strange
Now I just started car after erasing codes earlier and car ran very good then idle went from 800 to 1100 and check engine light came on it threw the PO304 again but no CTS code
Very strange
Last edited by Carloman61; 12-02-2021 at 10:55 PM.
#22
12-03-2021, 09:23 PM
If I follow, while the car is running and you check injector voltages, you are seeing the harness for the #4 injector having lower volts than the others? I'm trying to make sense of where that issue would be. I almost want to blame the PCM, but really not sure.
I pulled the shop manual data for troubleshooting P0118 and attached it.
I cannot say for the 3800, but I found out the old 3400 can run old fuel. Years ago I bought a 1999 Grand Am as a flip. Needed some work, had been sitting for about 1.5-2 years and had about half a tank of gas. I eventually started it on that tank and ran it and later topped off with good fuel. Never drained it. Ran it fine from best I could tell (even surprised me).
I pulled the shop manual data for troubleshooting P0118 and attached it.
I cannot say for the 3800, but I found out the old 3400 can run old fuel. Years ago I bought a 1999 Grand Am as a flip. Needed some work, had been sitting for about 1.5-2 years and had about half a tank of gas. I eventually started it on that tank and ran it and later topped off with good fuel. Never drained it. Ran it fine from best I could tell (even surprised me).
I guess my gas would have been ok
I also put some Lucas fuel additive in tank
#23
12-03-2021, 09:24 PM
If I follow, while the car is running and you check injector voltages, you are seeing the harness for the #4 injector having lower volts than the others? I'm trying to make sense of where that issue would be. I almost want to blame the PCM, but really not sure.
I pulled the shop manual data for troubleshooting P0118 and attached it.
I cannot say for the 3800, but I found out the old 3400 can run old fuel. Years ago I bought a 1999 Grand Am as a flip. Needed some work, had been sitting for about 1.5-2 years and had about half a tank of gas. I eventually started it on that tank and ran it and later topped off with good fuel. Never drained it. Ran it fine from best I could tell (even surprised me).
I pulled the shop manual data for troubleshooting P0118 and attached it.
I cannot say for the 3800, but I found out the old 3400 can run old fuel. Years ago I bought a 1999 Grand Am as a flip. Needed some work, had been sitting for about 1.5-2 years and had about half a tank of gas. I eventually started it on that tank and ran it and later topped off with good fuel. Never drained it. Ran it fine from best I could tell (even surprised me).
I guess my gas would have been ok
I also put some Lucas fuel additive in tank
#24
12-03-2021, 09:29 PM
Ok I finally got the #4 spark plug out after a bunch of choice words and stretching alot lol..
i found the electrode was light grey but there was some wet oil around base of electrode.
So I put an anti fouler over electrode and replaced plug..
We shall see what happens.
Back plugs are a B...
I'm replacing plug wires with some 8mm.
Wires and plugs are the NGK T55
i found the electrode was light grey but there was some wet oil around base of electrode.
So I put an anti fouler over electrode and replaced plug..
We shall see what happens.
Back plugs are a B...
I'm replacing plug wires with some 8mm.
Wires and plugs are the NGK T55
#25
12-05-2021, 04:14 PM
Ok everything is done as far as tune up.
drove car and al.ost immediately the check engine light came on and started flashing!
Got home and checked codes
Same code for CTS PO118 and PO304
And a new one for the Bank 1 sensor 2 on 02 sensors.. so I ordered both Sensors! Upstream and downstream
Plus I ordered all new fuel injectors..
We shall see what happens after that!
Still stumps me about the PO118 CTS circuit to high!
I replaced the sensor! Already..
But code keeps coming back..
drove car and al.ost immediately the check engine light came on and started flashing!
Got home and checked codes
Same code for CTS PO118 and PO304
And a new one for the Bank 1 sensor 2 on 02 sensors.. so I ordered both Sensors! Upstream and downstream
Plus I ordered all new fuel injectors..
We shall see what happens after that!
Still stumps me about the PO118 CTS circuit to high!
I replaced the sensor! Already..
But code keeps coming back..
#26
12-06-2021, 11:57 PM
Join Date: Jan 2008
Location: Mountains of Utah
Posts: 4,906
Hi, been reading your threads on this subject. You are really trying hard to resolve the issues. Texted my mechanic (one who built my Monte) and asked him : "Hi Matt, any idea why a PO118 CTS Circuit too high code would keep reoccurring?". He replied back: "Use a GM sensor. Pigtails give issues and PCM can be at fault (Not likely)". Hope this bit of info can spark a couple aha moments for you.
#27
12-07-2021, 05:08 PM
Ok so the sensor I got at AutoZone is Junk?
I will try your advice and see what happens..
Thanks for reply and info 👍
I will try your advice and see what happens..
Thanks for reply and info 👍
#28
12-10-2021, 04:12 PM
I just replaced all of injectors and still no change..
i had the PO300 come back after last time
So I erased it and now it came up with a PO306
When I give the car 4000 rpm's it pops through exhaust
The temp gauge worked for about 5 min then stopped and cooling fan came on..
So I erased those codes and started car up again.
This time no engine light. But still ran little rough.
I think this car is cursed!!
i had the PO300 come back after last time
So I erased it and now it came up with a PO306
When I give the car 4000 rpm's it pops through exhaust
The temp gauge worked for about 5 min then stopped and cooling fan came on..
So I erased those codes and started car up again.
This time no engine light. But still ran little rough.
I think this car is cursed!!
#29
12-10-2021, 09:29 PM
Join Date: Jan 2008
Location: Mountains of Utah
Posts: 4,906
I just replaced all of injectors and still no change..
i had the PO300 come back after last time
So I erased it and now it came up with a PO306
When I give the car 4000 rpm's it pops through exhaust
The temp gauge worked for about 5 min then stopped and cooling fan came on..
So I erased those codes and started car up again.
This time no engine light. But still ran little rough.
I think this car is cursed!!
i had the PO300 come back after last time
So I erased it and now it came up with a PO306
When I give the car 4000 rpm's it pops through exhaust
The temp gauge worked for about 5 min then stopped and cooling fan came on..
So I erased those codes and started car up again.
This time no engine light. But still ran little rough.
I think this car is cursed!!