changed my header and while i was doing that figured i would replace the O2 since its original....84,000 miles. now on a cold start (florida cold) it will stumble at first acceleration. once it warms up, it really doesnt stumble. its a bosch O2, could the sensor be bad?
fuel filter and pump were changed about 2 months ago and fuel pressure is good, so i ruled that out.
yup...throw it out and get a delco
new delco O2.....same problem. didnt change it at all. any other ideas?? i know the popular IAC and TPS. could coolant sensor be an option?
It was not the brand sensor, but your exhaust flow is the issue. You need a heated O2 sensor. Go to the performance section and search for heated O2 sensor.
FU Tuning
Ive seen the posts about the heated o2 before but didnt think about it since i already had a header on my car with no problems. only happened when i switched to the DC. i did notice the DC has the sensor on a different cylinder than the RK.
whiteboyz24 wrote:Ive seen the posts about the heated o2 before but didnt think about it since i already had a header on my car with no problems. only happened when i switched to the DC. i did notice the DC has the sensor on a different cylinder than the RK.
If I recall doesn't the Dc have the O2 sensor in the collector like the Pacesetter? It comes down to a flow issue. You are suffering from too good of flow (funny isn't it). Exhaust flow is to good and the O2 sensor is not getting to temp fast enough. The car goes into closed loop and runs like crap until the sensor is warm and working properly. A heated O2 sensor is one of the best mods I ever did to my car.
FU Tuning
nope. not on the LD9. its before the collector. only about 12" from the head on the cylinder closest to driver side. Maybe they changed the design.
whiteboyz24 wrote:nope. not on the LD9. its before the collector. only about 12" from the head on the cylinder closest to driver side. Maybe they changed the design.
I thought DC was the same design as Pacesetter. My pacesetter is in the collector. Still had the same issue. Not anymore!!
FU Tuning
the past 2 days it hasnt givenme any problems. even on the first day, i really didnt give it that much of a chance to bog since i got on the throttle right away. maybe it was just in my head the first day. im just going to run the 2 wire and see if it stumbles anymore. if it does i guess ill go to the heated one. thanks for the input
I am having the same prroblem with a stock header. I changed to a delco plug, and I am still have the sputtering problem. I am not throwing any codes though? Do you think I could need a heated o2 even with a stock header?
98z24, lowered 2", aem intake, cat-back striaght pipes!, cop ligths in the front and rear, 18" liquid metal's, primer black, tint, full audio and video.
matthew christian wrote:I am having the same prroblem with a stock header. I changed to a delco plug, and I am still have the sputtering problem. I am not throwing any codes though? Do you think I could need a heated o2 even with a stock header?
Possible. I had this issue on my old 97 Z24 with a stock manifold, but never tried a heated one. I also had a complete exhaust (except header)
FU Tuning
I too bought a $20 bosch upstream o2 sensor and my car sputters on cold florida starts. I have plans to change to acdelco sensor. But problem goes away once car is warmed up.
~1996 Cavalier LS 2.4L (auto)
whiteboyz24 wrote:Ive seen the posts about the heated o2 before but didnt think about it since i already had a header on my car with no problems. only happened when i switched to the DC. i did notice the DC has the sensor on a different cylinder than the RK.
just do it the o2 heated sensor mode trust me what john says it does work .
i have it done and no problems for 2 years now , bosch or delco do not matter .
It may have been a computer "relearning" issue. If it was, your problem is solved. Give it a few hundred miles before you make a decision.
