[karlmarkiewicz]

Finally replaced the second O2 sensor, it took two people and a meter long pipe to get it off. Although after replacing it with the new one, my car is now misfiring in one cylinder. It is the cylinder closest to the firewall, on the drivers side. Admittedly we were harsh on the wire going into the spark plugs, although no wires were unplugged. Also, when i jiggle, and pull at that misfiring cylinder, i can manage to position is so it doesn't misfire, although when i push it all the way it like it should be, it will begin misfiring.

Any ideas?

[atari4x4]

you've probably damaged the wires or plug in the loom. swap the coil pack with another one & see if it moves with the coil pack or stays on that cylinder.

[karlmarkiewicz]

atari4x4 wrote:

you've probably damaged the wires or plug in the loom. swap the coil pack with another one & see if it moves with the coil pack or stays on that cylinder.

I went and had lunch, then came back and turned the car on and it was not misfiring anymore. I wiggled the pack around a bit to see if i could make it misfire. After looking at it for like 10 minutes, very confused, i put the cover back on and took it for a test drive. There is a VERY slight decrease in power. I did a couple of 0 - 60km/h tests and got about 8.1 second where as before replacement i got about 7.5 seconds. It could just be the situation isn't as good as when i did the previous speed test, but there is certainly no increase in power AT ALL. I read up on some other forums and people said after replacing the sensor they had a smoother ride and the like, I have noticed nothing (may be normal, just letting you know).

[atari4x4]

Disconnect the battery for 10 mins, then take it for a couple reasonable drives... But drive it like you stole it!

[karlmarkiewicz]

atari4x4 wrote:

Disconnect the battery for 10 mins, then take it for a couple reasonable drives... But drive it like you stole it!

Hahah, will do. Thanks.

[DarkHorse]

The difference in performance (smoothness or power) will depend on how badly screwed the old sensors were. Seat of the pants performance may not have changed that much... or if it was running rich before there may well be a decrease in power at WOT.

As long as the ECU isn't throwing codes any more just stop worrying about it

[karlmarkiewicz]

DarkHorse wrote:

The difference in performance (smoothness or power) will depend on how badly screwed the old sensors were. Seat of the pants performance may not have changed that much... or if it was running rich before there may well be a decrease in power at WOT.

As long as the ECU isn't throwing codes any more just stop worrying about it

I just took it for a spin for about 10 minutes, after unplugging my battery for 10 minutes. Regular driving feels normal, the decrease is power is not worth worrying about. Although, i know there is a decrease because one, the speed test showed there was a decrease, and two, the idle used to be enough to drive the car out of my driveway, although now i need to accelerate to get over the hump.
Also, it still feels the same at idle, which to me, feels a bit rough.

All i'm really concerned about is that, my old sensor was stuffed enough to throw a code, although the new ones have done absolutely nothing. I guess I won't be able to tell whether they have done something until I test the fuel consumption properly, also, I need to drive it a bit more to see if any codes pop up again.

Is there any chance the plug on the engine side (opposed to the plug attached to the sensor) is broken or faulty?

[atari4x4]

OMFG, what do you think o2 sensors actually do, magical 100kw turbo boost?

how many kms have you done now with the new sensor & have they thrown a code yet, if not stop stressing FFS.

did you stop & think that maybe the o2 sensors have been rooted since the day you got it & it's been running rich the whole time?

there is a chance that the plug might be damaged, about 1 in 100,000 unless you fucked it trying to remove the old sensor & a phone app is hardly an accurate way to measure performance.




come back to us in a week or 3 when you've got a few tanks of fuel through it

[karlmarkiewicz]

atari4x4 wrote:

OMFG, what do you think o2 sensors actually do, magical 100kw turbo boost?

how many kms have you done now with the new sensor & have they thrown a code yet, if not stop stressing FFS.

did you stop & think that maybe the o2 sensors have been rooted since the day you got it & it's been running rich the whole time?

there is a chance that the plug might be damaged, about 1 in 100,000 unless you fucked it trying to remove the old sensor & a phone app is hardly an accurate way to measure performance.




come back to us in a week or 3 when you've got a few tanks of fuel through it

Hahah, no. I understand what they do, I have just been researching what other people have noticed with them, and they have noticed a difference. Not stressing.
Yeah, ill drive is for a while, check the codes then get back to you.

Thanks for your help.

[JrZook]

DarkHorse wrote:

The difference in performance (smoothness or power) will depend on how badly screwed the old sensors were. Seat of the pants performance may not have changed that much... or if it was running rich before there may well be a decrease in power at WOT.

IIRC, the O2 sensors have no bearing on WOT conditions as the ECU switches into open loop mode and doesn't use their input..

[droverdave]

Is it a wideband or a narrow band o2 sensor we're talking about here?

The photo on the previous page appears to have a number of wires on it, which to me sounds like a wide band sensor (with the heater etc).

[atari4x4]

it's just a stock 4 wire heated jobby, i think they're narrow band but unsure.

[JrZook]

Narrow-band. They can be heated or not.

[DarkHorse]

JrZook wrote:

DarkHorse wrote:

The difference in performance (smoothness or power) will depend on how badly screwed the old sensors were. Seat of the pants performance may not have changed that much... or if it was running rich before there may well be a decrease in power at WOT.

IIRC, the O2 sensors have no bearing on WOT conditions as the ECU switches into open loop mode and doesn't use their input..

Fair point. I was just using WOT as shorthand for hard accelleration rather than actual foot-through-the-floor, since he was complaining about his 0-60 times being worse.

[cairns27]

Hey I don't even have O2 sensors, but this was a good read.....thanks

bye

[alexxx]

Bye..

[atari4x4]

[sideways]

Atarisplosion.

[karlmarkiewicz]

Hahahahaha

[atari4x4]

been a couple weeks, hows the economy looking?

just been having a look at the SV620 FSM & it states to replace the heated (4wire) o2 Sensors every 80,000kms or 60 months.

[karlmarkiewicz]

atari4x4 wrote:

been a couple weeks, hows the economy looking?

just been having a look at the SV620 FSM & it states to replace the heated (4wire) o2 Sensors every 80,000kms or 60 months.

Hi, i hate to say it, and it is the reason why i haven't posted the economy yet as i am hoping it will improve, but the economy is exactly the same. still getting roughly the same economy and i have drive all three driving types, off-road, highway, and urban. I've done calculations and it is roughly about the same as it was before the sensors, the improvement is extremely marginal. I am hoping a few more tanks through it and it will improve :/
Although, good news is, after 2 weeks of driving i pull the codes on it and i got code 12 (blink *pause* blink-blink) so, the 02 Sensors are causing any errors now.

[atari4x4]

what size tyres are you running & are you accounting for the larger rolling diameter?

have you tried putting premium in it again?

ever had a look at the cat converter, how many kms on the clock?

[karlmarkiewicz]

atari4x4 wrote:

what size tyres are you running & are you accounting for the larger rolling diameter?

I was going to ask you about this actually. I am running 30 inch tyres (stock are 27 inch), and No i have not accounted for the larger rolling diameter. Although i was not accounting for larger rolling diameter before 02 Sensors were installed. Also when i was running stock (27 inch) tyres i was still getting sh*ty economy. I am not sure exactly how to account for them, I read some forums a while back about how to do it, but i forgot. I will google it now.

atari4x4 wrote:

have you tried putting premium in it again?

I have not, I will when fuel settles down a bit, premium is over $1.70 a litre.

atari4x4 wrote:

ever had a look at the cat converter, how many kms on the clock?

I have been meaning to get someone to check it out for a very long time, although i go to University 5 days a week and mechanics around me are always shut weekends.

[karlmarkiewicz]

Also it has done 156,000

[atari4x4]

http://www.tyrestore.in/upsizing.htm

[karlmarkiewicz]

atari4x4 wrote:

http://www.tyrestore.in/upsizing.htm

Check the link for my results, easier to send it via link. http://puu.sh/3Q8lT.png
EDIT: I worked out, at a difference of 9.4%, if i do 300 km on the odo i am really doing 328. So that means, according to the odo i am getting 20L/100K but really, i am getting 18.3L/100K. Sound about right?

Also, i have changed my diff ratios from 4.6 to 5.12, which apparently is suppose to lower that percentage difference a bit?

[atari4x4]

pretty sure the auto V6 SV620's are 4.8 from factory & are your tyres 215/82r16 or 215/85r16?

i get 12.54% difference when going upto a 215/85r16 profile (30.4"), with the 5.12's your speedo/odo should be pretty close to being correct. have you checked it against a GPS?

[karlmarkiewicz]

atari4x4 wrote:

pretty sure the auto V6 SV620's are 4.8 from factory & are your tyres 215/82r16 or 215/85r16?

i get 12.54% difference when going upto a 215/85r16 profile (30.4"), with the 5.12's your speedo/odo should be pretty close to being correct. have you checked it against a GPS?

Sorry, you're right stock is 4.8. To be honest, i just googled an imperial to metric converter and it spat out 82 when i put in 30 inch and 8.5 inch wide. As for the diff, I know for a fact the speedo is still out, however i don't know exactly how much by. It may have fixed it slightly but i would say it is still out by about 8 or so percent. So keep up with cars next to me in a 60 zone i have to go about 56km and on the highway in a 100 zone i have to go just over 90. The new diff ratio did not give me a noticeable difference for both the speedo and performance.

[atari4x4]

so what size are you tyres?

[karlmarkiewicz]

Okay, so made a few mistakes about my tyre sizes, i do apologize. Here are the correct (hope so) sizes:

My stock tyres read 215/70/R16 (27.9 Inch, 8.5 Inch wide)
My new tyres (According to google) are 215/85/R16 (30.4 inch, 8.5 wide)

With these new measurements here is the updated difference: http://puu.sh/3Q92r.png

EDIT: They are retread tyres that i have on now, and the side says 245/70/16 which is obviously not right. The guy i bought them off just said they were 30 inch tyres and they fit a 16 inch rim. That is all i am going off sorry.