Gas pedal response messed up

phi1542

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What are you replacing it with? I spent 5-6 hours with my friends '98 4 cylinder doing the catalytic converter. I wasn't letting that sucker beat me. Haha! I did eventually win.

Also, phi, the rear sensor is of little concern. It doesn't affect how the car runs. It just monitors catalytic converter activity.

So all I need is this one? http://www.amazon.com/Denso-234-4621-Oxygen-Sensor/dp/B000C5YCUM

would the upstream one still give me a P0420?
 
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james'99

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So all I need is this one? http://www.amazon.com/Denso-234-4621-Oxygen-Sensor/dp/B000C5YCUM

would the upstream one still give me a P0420?

Crap... Sorry, I forgot you had the P0420... Have you checked for exhaust leaks before the cat. Fresh air sucking in can also cause an issue.

Yes... The upstream could cause it, but highly unlikely and very indirectly.

The link you provided is for the downstream sensor which would/will be the correct one if everything else checks out. Your original video may also point us to a clogged catalytic converter now that I think about it. xci, what do you think of this?

http://www.youtube.com/watch?v=QiHlU9WNha4&feature=youtu.be

V6 Upstream (Before Cat, On Header/Downpipe): Click Here, Denso 234-4727

V6 Downstream (On Cat): Click Here, Denso 234-4621

Ever hear of an IR thermometer, phi?

572-2-c-02a-600x402.jpg


Basically, the test is that the cat should be at least a 100 degrees hotter at the tail end than the inlet end. Call it an oven of sorts. Basically, drive the car around a while, then get the IR thermometer nice and close to the front of the cat to reduce interference. Do the same thing for the rear. You'll do this on the actual piping as close as it gets to the actual cat.

https://www.youtube.com/watch?v=9VZ5K8n5jj0
 
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phi1542

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Crap... Sorry, I forgot you had the P0420... Have you checked for exhaust leaks before the cat. Fresh air sucking in can also cause an issue.

Yes... The upstream could cause it, but highly unlikely and very indirectly.

The link you provided is for the downstream sensor which would/will be the correct one if everything else checks out. Your original video may also point us to a clogged catalytic converter now that I think about it. xci, what do you think of this?

http://www.youtube.com/watch?v=QiHlU9WNha4&feature=youtu.be

V6 Upstream (Before Cat, On Header/Downpipe): Click Here, Denso 234-4727

V6 Downstream (On Cat): Click Here, Denso 234-4621

Ever hear of an IR thermometer, phi?

572-2-c-02a-600x402.jpg


Basically, the test is that the cat should be at least a 100 degrees hotter at the tail end than the inlet end. Call it an oven of sorts. Basically, drive the car around a while, then get the IR thermometer nice and close to the front of the cat to reduce interference. Do the same thing for the rear. You'll do this on the actual piping as close as it gets to the actual cat.

https://www.youtube.com/watch?v=9VZ5K8n5jj0

I haven't checked but I will when I change my oil. Clogged cat? No way... I just bought it a few months ago though. I did do a seafoam and I don't tbink I got all of it out and it sat there for like a day. I did seafoam again to get it all out but idk if it messed everything up. Seafoam in the pcv btw. No I don't have that tool =T
 

james'99

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I haven't checked but I will when I change my oil. Clogged cat? No way... I just bought it a few months ago though. I did do a seafoam and I don't tbink I got all of it out and it sat there for like a day. I did seafoam again to get it all out but idk if it messed everything up. Seafoam in the pcv btw. No I don't have that tool =T

Well, if the cat is new, change the O2 sensor. I think that is safe to say. I'd change both in your dilemma.
 

phi1542

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Ok thanks I'll change both O2 sensors. I doubt I have a exhaust leak in the header because his code was never here before and my car hasn't been low for a long time but I'll still check
 

phi1542

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I've also noticed a slight lag when I start the car. It use to start instantly but now it lags for a couple seconds idk if that's normal. And my gas tanks goes to empty hella fast now wtf. Everything was cool until I touched the EGR.... Idk what happened. My dad did start the car and rev the car a little without the egr in too if that did anything
 
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james'99

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I've also noticed a slight lag when I start the car. It use to start instantly but now it lags for a couple seconds idk if that's normal. And my gas tanks goes to empty hella fast now wtf. Everything was cool until I touched the EGR.... Idk what happened. My dad did start the car and rev the car a little without the egr in too if that did anything

Change sensors, clear monitors. Let's start there
 
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