Gen 4 Pace Setter Exhaust Manifolds / Headers

[CAN-03runner]

Not trying to down your mechanic but how did he tell you he determined it was definately an o2 problem? I did the same swap but installed all 4 sensors myself while truck was on lift and still get a po420 or po430 code(manifold running below threshhold). I did some research myself and cleared up the problem code by cleaning my mass air meter and ridding of my cone air intake and putting stock box back on. Cleared codes and have seen none since. Love the new found gas mileage, torque, and hp with these pacesetters and full on custom exhaust

I did both sides with pace setter, toyota gaskets, and 4 denso new sensors. I got the P0430 soon after. Sometimes it goes away on it's own. Sometimes I need to clear it, and it comes back almost right away or sometimes after a few days, sometimes it comes on after a long fast highway drive sometimes not...basically I can't find a pattern.

I replaced the donut/exhaust seal right after the both cats with toyota OEM. Not fixed, code comes back after a few days. When I first got the P0430 years ago, changing the exhaust seals fixed it for quite some time. I have the seal in hand for the Y connection now. I will try that one next, and verify the O2 connections.

But...hmmmm Mass Air Meter, is that another name for Mass Air Flow sensor, which is pluged in right on top where the air box is. That is easy to clean, I have not done that since many years.

 

[gshadow325]

Well I have changed both manifolds and all four sensors with 3 denso and one oem. So Both manifolds are new, all four sensors are new and I still get p0430 codes. Going to spacer the o2 on passenger side and see if that helps.

 

[gshadow325]

Btw, my maf is new also.

 

[WXman]

Seems to me like a common theme here is that the people who change their O2 sensors are the ones getting the light on the dash. So it's possible this has absolutely nothing to do with the manifolds.

 

[jgmass]

My P0420 code arrived on my driver side within a day of getting my Pacesetter manifolds installed. They reused the original sensors on the manifolds.

I thought replacing sensors would fix me up, but the CEL came back time after time. I replaced the manifold one first, then the downstream one. Frustrated, I finally added a spacer to the downstream O2 and the CEL finally went away.

The weird thing is that this only happened on the driver side. The passenger O2 sensors are still original...

 

[WXman]

My P0420 code arrived on my driver side within a day of getting my Pacesetter manifolds installed. They reused the original sensors on the manifolds.

I thought replacing sensors would fix me up, but the CEL came back time after time. I replaced the manifold one first, then the downstream one. Frustrated, I finally added a spacer to the downstream O2 and the CEL finally went away.

The weird thing is that this only happened on the driver side. The passenger O2 sensors are still original...

Well there goes my theory.

 

[CAN-03runner]

I did both sides with pace setter, toyota gaskets, and 4 denso new sensors. I got the P0430 soon after. Sometimes it goes away on it's own. Sometimes I need to clear it, and it comes back almost right away or sometimes after a few days, sometimes it comes on after a long fast highway drive sometimes not...basically I can't find a pattern.

I replaced the donut/exhaust seal right after the both cats with toyota OEM. Not fixed, code comes back after a few days. When I first got the P0430 years ago, changing the exhaust seals fixed it for quite some time. I have the seal in hand for the Y connection now. I will try that one next, and verify the O2 connections.

But...hmmmm Mass Air Meter, is that another name for Mass Air Flow sensor, which is pluged in right on top where the air box is. That is easy to clean, I have not done that since many years.

Update: I had the P0430 before the pacesetter swap, with original O2 sensors and now with replacement sensors. Sensors changed during the manifold install, not because they were suspect but just as maintenance and new with new. All bolts, gaskets, and heat sheild were replaced with new Toyota parts.

Still had the code until now. I finally managed to put in the spark plug non fouler fix. It's been about a week and CEL has not come back on.

The bad news, there has been for about a month now an awful rattle in what seems to be inside the manifold, before the CAT on the passenger side. Sounds similar to sound made by a loose heat sheild or loose rusty rattling exhaust pipe. Nothing is loose or rusty on the outside.

This started to occur when we had an extreme cold spell in December. I wonder if the freeze, heat up, freeze heat up etc... caused some metal part on the inside like welding slag or something to come loose and is now bouncing around over the CAT honey comb, making it be "less efficient". Maybe this was already sitting covering some of the CAT honey comb causing it to throw a CEL and now the heat and cold caused it to losen and is bouncing around.

Und Zoh, if anyone still has not installed theirs, or is contemplating it, if you have access to something like a plumbing camera, maybe you should fish it inside and get a visual of what might flake off later on, or at least shake and tap it upside down and watch for any falling debris.

It was such a pain to get that manifold in there. I'm going to see if a mufler shop is able to just cut off the cat, clean out what is rattling and weld the cat back on....but probably won't be able to go all the way around.

 

[oljedi11950]

Dang I just started getting this noise too , thought it was front oem skid but NOT! WTF I know I saw someone post about 6 months ago about this very noise ?

 

[gshadow325]

Update: since doing both manifolds with pace setter. I got a pesky p0430 code that was reoccurring. Did a spacer mod on the passenger side down stream and it has been gone since a few days after my last post. I too changed all my sensors all my manifolds to new ones. But have been error free for the last 3500+miles

 

[oljedi11950]

Update: since doing both manifolds with pace setter. I got a pesky p0430 code that was reoccurring. Did a spacer mod on the passenger side down stream and it has been gone since a few days after my last post. I too changed all my sensors all my manifolds to new ones. But have been error free for the last 3500+miles

Gshadow this spark plug spacer mod work on V6 ?

 

[gshadow325]

Gshadow this spark plug spacer mod work on V6 ?

it should, dont see why not.

 

[oljedi11950]

Ok cool gonna go back & check your posts on it out . Thanks

 

[Toyota4ever]

Hi everybody, just wanted to revive this thread and share my experiences with the exhaust manifolds.

I bought a 2005 V8 2 years ago with both manifolds cracked. I am in the parts business so got a very good deal on the Magnaflows and had them both replaced. One year later, the driver side cracked, had that replaced under warranty. Now 2 years later, both sides are cracked once again. I like the truck and I need the V8 for towing so I am currently looking for replacements. I am seriously looking at getting them from the dealer but I am wondering how everyone else is doing with theirs and if there are any updates / changes / new products?

I think one of the main problems is the fact that there is not enough flex in the exhaust at the manifolds. Unfortunately, because of the cats and the bends there is no room to squeeze a little flex pipe into the tubes. Those 2 spring bolts at the bottom are not enough.

 

[rjb75]

You're saying that you cracked two Magnaflow manifolds? Where are they cracking?

 

[CruzadoBlanco]

Hi everybody, just wanted to revive this thread and share my experiences with the exhaust manifolds.

I bought a 2005 V8 2 years ago with both manifolds cracked. I am in the parts business so got a very good deal on the Magnaflows and had them both replaced. One year later, the driver side cracked, had that replaced under warranty. Now 2 years later, both sides are cracked once again. I like the truck and I need the V8 for towing so I am currently looking for replacements. I am seriously looking at getting them from the dealer but I am wondering how everyone else is doing with theirs and if there are any updates / changes / new products?

I think one of the main problems is the fact that there is not enough flex in the exhaust at the manifolds. Unfortunately, because of the cats and the bends there is no room to squeeze a little flex pipe into the tubes. Those 2 spring bolts at the bottom are not enough.

if you really want dependability doug thorly now makes headers for the 2005 and up v8 4runners. if i could afford them i would get them and just have them ditch the air tube for me.

 

[Fleethammer]

I had the exact same experience with my Magnaflow manifolds they cracked shortly after replacing them. I also had to replace my Y-pipe since the stock one had rusted out that was also Magnaflow and that didn't line help correctly. rrectly. I had a garage weld in a flex pipe section for a front wheel drive car on the passenger side of the y pipe after getting the manifolds welded. the passenger side hasn't cracked yet but my driver side has cracked again. That's the short version of the story not counting how many times I had to have the y pipe welded by different shops because no one can seem to weld correctly in New YorkYork State or the oxygen sensors that I had to replace blah blah blah. well 2000 dollars later I'm back where I started the truck actually sounds worse than it ever did. These Doug Thorley headers do they fit all 2005 and up V8?

Hi everybody, just wanted to revive this thread and share my experiences with the exhaust manifolds.

I bought a 2005 V8 2 years ago with both manifolds cracked. I am in the parts business so got a very good deal on the Magnaflows and had them both replaced. One year later, the driver side cracked, had that replaced under warranty. Now 2 years later, both sides are cracked once again. I like the truck and I need the V8 for towing so I am currently looking for replacements. I am seriously looking at getting them from the dealer but I am wondering how everyone else is doing with theirs and if there are any updates / changes / new products?

I think one of the main problems is the fact that there is not enough flex in the exhaust at the manifolds. Unfortunately, because of the cats and the bends there is no room to squeeze a little flex pipe into the tubes. Those 2 spring bolts at the bottom are not enough.

 

[rjb75]

Has anyone that had cracked Magnaflows had them re-welded?

 

[JKC2638]

I'm new here and was looking for info about headers and found this thread. I see all the problems with the P0430 codes. Here is a little insight into why this happens.
The material that many aftermarket cats are made of is not sufficient to clean the exhaust properly. Changing the sensors is a waste of money. This is why they are so much cheaper. Has nothing to do with build quality but the very expensive material that makes up the honeycomb inside. In NY you can't buy any aftermarket cats now. It is illegal. They are a good value but you have to put up with the CEL sometimes or get O2 "cheaters" that fool the ECU into thinking the cats are doing their job.

 

[Fleethammer]

Has anyone that had cracked Magnaflows had them re-welded?

Yep, they crack just as easily as the stockers. I agree with the above post that they just can't take any amount of weight on them. Installing the flex pipe from a front wheel drive car into the passenger side of my y- pipe has prevented my passenger side manifold from cracking again but there's no room to get a flex pipe section on the drivers side of the y pipe, so my driver side manifold is cracked again. Fml

 

[rjb75]

Well this sucks. I had the drivers side done with a Magnaflow a month ago and it's leaking again. Haven't had the time to take it apart to check for cracks yet but I have to say this is ridiculous. [MENTION=108235]CruzadoBlanco[/MENTION] how will installing the Doug Thorley's solve this problem?