Headers or downpipe?

What's the proper way to delete the rear o2 sensor? I keep getting the 140 code so I just changed it so the code was disabled and errors were not reported. Anything I missed or should change?

matt270avian wrote:

What's the proper way to delete the rear o2 sensor? I keep getting the 140 code so I just changed it so the code was disabled and errors were not reported. Anything I missed or should change?

Nope, you're good. You should actually turn off....

P0137
P0138
P0140
P0141

Those are all the rear O2 codes.

Abaddon wrote:

matt270avian wrote:

What's the proper way to delete the rear o2 sensor? I keep getting the 140 code so I just changed it so the code was disabled and errors were not reported. Anything I missed or should change?

Nope, you're good. You should actually turn off....

P0137
P0138
P0140
P0141

Those are all the rear O2 codes.

Alright. The only code I've gotten is the one for the heater control circuit or whatever. If need be I'll turn the other ones off.

I disabled both P0140 and P0420 (value "3"). P0140 trips SES from sensor inactivity. P0420 trips SES when O2 sensors 1 and 2 have similar readings (indicating cat conv isn't doing its thing). If you delete the rear sensor, you shouldn't throw a P0420 code, but if you keep the rear sensor on the car, you probably would see this DTC.

I keep P0137, P0138, and P0141 active (stock value). Haven't seen a code from these. If it ain't broken...

Certain groups of dtc's have modal relationships so if the criteria is met for one code then other ones dealing with the same system will not be set because one or more criteria is logically unreliable

AA wrote:

I disabled both P0140 and P0420 (value "3"). P0140 trips SES from sensor inactivity. P0420 trips SES when O2 sensors 1 and 2 have similar readings (indicating cat conv isn't doing its thing). If you delete the rear sensor, you shouldn't throw a P0420 code, but if you keep the rear sensor on the car, you probably would see this DTC.

I keep P0137, P0138, and P0141 active (stock value). Haven't seen a code from these. If it ain't broken...

I still have a cat, but I think its just the cheap sensor I used causing the one code to go off. I haven't even gotten the other codes usually caused by a high flow cat yet.

The P0140 should indicate the trouble is with the rear O2 sensor. A P0420 would suggest a deleted or bad (or high-flow) cat.

Hey guys yesterday I did a tune up on my car and when installing the spark plug in the front middle cylinder I noticed that my headers had a small hair line fracture in it. I knon you can't really fix the, sine they are cast iron, I'm just wondering if this will be a big deal? I've thought about installing some after market ones to complement the DP and cat back I have, but I live in CA and its a pain. And ideas or advice would be great.

Thanks

Depends on what you want from the car. You can drive it, but the noise will probably get louder. If you want the smooth, lux Riviera ride, find a rear mani at a salvage yard. Can't bd more than $50. It's not too bad, but it's a job. 4-6 hours.

Or, if you want to wake up the Riv and get a little more power, a set of headers will get you a mild but noticeable mid/top end gain, more if you add other mods. Also headers are a weight reduction, something that our cars appreciate! If you've ever run headers, you know they are louder than cast manis, but Rivs are well insulated, so windows up you are good. Wrapping the primaries, crossover, and flex pipe also helps with noise.

Best of luck.

Thanks AA. And I'm assuming that if I do decide to up grade the headers the best option for the riv is still the slp headers?

97SC_CALI_RIV wrote:

Thanks AA. And I'm assuming that if I do decide to up grade the headers the best option for the riv is still the slp headers?

I really do love my zzp stainless headers. They go on super easy and the quality is awesome.

I like my SLPs, but they were pricey, and are probably getting hard to find.

Thanks guys

97SC_CALI_RIV wrote:

to complement the DP and cat back I have

Don't forget, new headers won't work with your existing DP. I'm assuming you have a 3" DP from what you said, so your best bet would probably be to chop off the HF cat right after the flex pipe on your DP, then weld it on to your new headers to match up to your existing system.

Ah crap, yes I have the hogan down pipe. I like that thing too. I wonder if I can modify the headers to be like a "bolt on" straight to the DP?

97SC_CALI_RIV wrote:

Ah crap, yes I have the hogan down pipe. I like that thing too. I wonder if I can modify the headers to be like a "bolt on" straight to the DP?

Your best bet if you wanted to save some money would be to sell the DP and just buy new headers and a nice cat. If you don't care about cutting the existing downpipe up you could probably save the cat. Most headers use a slip on style DP (IIRC) while the OEM setup is bolt on.

Thanks Matt.

Just get the headers and be done with it IMO. This way, any and pretty much all future mods are covered exhaust wise....the engine can only be modded so far on stock manifolds.

I have the "knock off" SSAC headers. They've been on the car for quite some years now. The only issue I've had with them is that the giant flex joint rusted out, and I had to have an exhaust shop weld in a new one. I chalk this up to driving it year round (lots of snow and salt). I honestly see no point to spend all that money on SLP's. But, that's my opinion. I also wrapped and painted the entire header system, so that might have something to do with the longevity I've gotten out of them.

Hey! I found some exhaust parts for sale on this forum!

https://rivperformance.editboard.com/t11293-for-sale

charlieRobinson wrote:

Hey! I found some exhaust parts for sale on this forum!

https://rivperformance.editboard.com/t11293-for-sale

He already has a cracked front mani, not sure he wants another cracked one

matt270avian wrote:

charlieRobinson wrote:

Hey! I found some exhaust parts for sale on this forum!

https://rivperformance.editboard.com/t11293-for-sale

He already has a cracked front mani, not sure he wants another cracked one

Downpipe, bro. Downpipe.
And this manifold is actually repairable unlike the iron casted stock one.

In defense of stock manifolds, a Riv has ran a high 12 sec 1/4 mile on stock manis, downpipe + NO2 and a few other mods. The manifolds aren't that restrictive, especially the rear side. Adding a front header or power log is less difficult and more affordable, with decent breathing improvements. A lot of it is based on how much you want to spend.

For me, headers were a neat, convenient way to dress up the engine bay, shed some extra weight, and get the flow benefits needed for future modding. They're not free, but not everyone likes the idea of Frankensteining dissimilar exhaust parts for gains just to save a buck. For those on a tighter budget, stock manis can be made to breath pretty well.

I had forgotten about the power logs. They seem a better option for me right now, and it doesn't seem like it would be to diffuIcult since it's all in the front.

Question the the full set of headers, was it really a pain to swap out the ones in the back?

97SC_CALI_RIV wrote:

Question the the full set of headers, was it really a pain to swap out the ones in the back?

I have the luxury of a lift, so my install was easy for me. I'm pretty sure it's a fuggin pita, if not damn near impossible without a lift. If you got the car up off the ground far enough to lay under (with arm room), it could be done. I'm sure that's how most people do it.

Abaddon wrote:

97SC_CALI_RIV wrote:

Question the the full set of headers, was it really a pain to swap out the ones in the back?

I have the luxury of a lift, so my install was easy for me. I'm pretty sure it's a fuggin pita, if not damn near impossible without a lift. If you got the car up off the ground far enough to lay under (with arm room), it could be done. I'm sure that's how most people do it.

Scott, when I took mine off and put them back on, I did it completely from the top side. It wasn't the most fun thing ever, but it wasn't awful by any means.