Car Stumbling, bogging. Need some help
Thread Starter
Burning Brakes
Joined: Nov 2010
Posts: 924
Likes: 43
From: Goldsboro, NC
Car Stumbling, bogging. Need some help
A little backround on the car..Its a 2001 Z06, forged p1sc, fast intake, fast rails, longtubes ect.
I just put a different cam in the car and am having a real bad stumble. The car idles fine, and drives good when it is cold but as soon as it warms up I get the stumble or bog. Almost sounds like a miss. It usually bogs when i am on the throttle a little bit all the way to about 1/4 throttle then it catches itself and takes off. Another weird thing is it bogs and sounds like its misfiring if i am in neutral and rev it up and hold it at any rpm setting.
Things I have done so far..Brand new plugs, Wires, map sensor, new o2 sensors ( which I had crossed so I thought that was my problem but switched them and still the same) Checked my o2 sensor fuse..which was blown, put new one in..no difference. car has been tuned in speed density but has NOT been tuned with the new cam. Plugs are also pretty black.
What I am thinking at this point is.... 1- its just a tune and the only reason I dont think it is, is because my old z06 and did a heads and cam swap on it and it never had this issue untuned. .
2- I extended the o2 sensors myself, is this bad?
3- o2 sensors got messed up when I had them crossed.
I pulled codes and the only ones im getting are p0103 and p0102 which I believe are because its tuned in Speed density.
Any help is GREATLY appreciated, I hope to have the car back on the road soon! Thanks
I just put a different cam in the car and am having a real bad stumble. The car idles fine, and drives good when it is cold but as soon as it warms up I get the stumble or bog. Almost sounds like a miss. It usually bogs when i am on the throttle a little bit all the way to about 1/4 throttle then it catches itself and takes off. Another weird thing is it bogs and sounds like its misfiring if i am in neutral and rev it up and hold it at any rpm setting.
Things I have done so far..Brand new plugs, Wires, map sensor, new o2 sensors ( which I had crossed so I thought that was my problem but switched them and still the same) Checked my o2 sensor fuse..which was blown, put new one in..no difference. car has been tuned in speed density but has NOT been tuned with the new cam. Plugs are also pretty black.
What I am thinking at this point is.... 1- its just a tune and the only reason I dont think it is, is because my old z06 and did a heads and cam swap on it and it never had this issue untuned. .
2- I extended the o2 sensors myself, is this bad?
3- o2 sensors got messed up when I had them crossed.
I pulled codes and the only ones im getting are p0103 and p0102 which I believe are because its tuned in Speed density.
Any help is GREATLY appreciated, I hope to have the car back on the road soon! Thanks
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
QUOTE"
I just put a different cam in the car and am having a real bad stumble"
If you have not had the PCM retuned, your shooting in the dark...
Car operates fine cold but bad after warmed up. Your O2 sensors MUST be working correctly to make part throttle operation smooth and reliable.
Are you SURE that you have properly operating O2 sensors??? The heater circuit MUST be fully operational. Just because the fuse is good does NOT mean that you have operational heaters. Measure heater voltage AT the FUSE (KEY ON) amd measure O2 sensor connector heater fise power and ground wire resistance at the O@ sensor connector.
Use the schematic and do basic continunity, voltage and resistance checks.
The DATA LOG will tell you GOBS of info about the way your engine is running!
Bill
My recommendations would be to DATA LOG the PCM and look at LTFT and O2 sensor operation
I just put a different cam in the car and am having a real bad stumble"
If you have not had the PCM retuned, your shooting in the dark...
Car operates fine cold but bad after warmed up. Your O2 sensors MUST be working correctly to make part throttle operation smooth and reliable.
Are you SURE that you have properly operating O2 sensors??? The heater circuit MUST be fully operational. Just because the fuse is good does NOT mean that you have operational heaters. Measure heater voltage AT the FUSE (KEY ON) amd measure O2 sensor connector heater fise power and ground wire resistance at the O@ sensor connector.
Use the schematic and do basic continunity, voltage and resistance checks.
The DATA LOG will tell you GOBS of info about the way your engine is running!
Bill
My recommendations would be to DATA LOG the PCM and look at LTFT and O2 sensor operation
