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Is the test at idle or on a dyno?
Egr worked splendidly and managed to kill the motor at idle during the test. The gasket was indeed the problem. Thank you for saving me from a stupid purchase!
I apologize for my wordy posts.
PASSSSSSSSSSSSSSSED IT!!! lots of that after work tonight, haha.
Interestingly, HC and CO, while still very low, were three times higher than they were during the runs without the EGR working. CO2 was nice and high indicating a good mixture, not lean.
So, I must admit that while I was hating on emissions at the beginning of this adventure I am glad to have gone through this. My truck is running better than it ever has and I assume I fixed some vacuum leaks along the way. I have a ton of low end grunt and the idle is rock solid. Also, a note for EGR. I do not notice any difference or loss of power in the upper rpms. I do not know why people disable this system, maybe just for some myth that EGR will rob horsepower, or that if a system is there to help emissions it must be from big brother trying to control our lives. My butt dyno tells me it does nothing to hurt the power output, and lowering cylinder temps can ONLY be a good thing for the motor.
Likely caused by the additional 2 clicks in the AFM and the recirculating of exhaust gases into the intake. Also, if you have a high flow cat, it may not get hot enough to burn the HC's and CO's under test conditions, the baffle that emsvitil posted will slow the gas flow down, allowing the cat to burn hotter. I think those that stripe the emission stuff, usually fall into one of two camps, "it robs HP", or "too cheap to replace it when it parts fail", the second I understand, if you don't have to pass a test every other year or so why would you spend a couple hundred on replacement parts or hours chasing down a problem. However, what most people forget is that unlike the engines of the mid to late '60's, where smog equipment was just slapped on to meet the newly introduced emission standards, engines since then have been designed along with the emission equipment, and simply deleting the equipment without correcting for it, usually ends up having a negative effect on performance.
Hope you get to working on your truck soon!Remflex's description of the 7002 says "for header applications." I asked them at the time if I wanted the 7002 or 7010 and never heard a response, so I just went with the 7002. The 7002 says it has "EGR Gaskets" included but I think they are talking about external piping for carb applications, not the manifold gasket (clearly.) It is a little misleading. I noticed during this swap that the shop that assembled this stuff used 4 bolts and 4 studs on the exhaust, rather than 8 studs. With the Remflex it did not matter, it only gets torqued to 20 ft/lbs. But, with the "normal" gasket, I was a bit scared to torque up to 35 ft/lbs. I don't think you can tighten that far into aluminum although I could be wrong. I did not want to risk it. So, there is a slight leak at the flange that maybe would be gone at 35 ft/lbs, i don't even notice it with the radio on. But I will order up some toyota studs when I get the 7010 gasket. Another benefit of the remflex is that it is a thicker gasket, easily double a stock gasket, so if you cut out the unnecessary gasket material between the exhaust and EGR ports, you will be making an even larger channel for the EGR flow.I plan on using a lock washer and standard nut instead of the crimped self-locking nuts.
emsvitil, what header do you have? I seems reasonable that something like the LCE, where the EGR notch may be too small, requires a bit of extra backpressure to force exhaust gasses through there. I thought since mine killed the motor so easily at idle that it would be fine at speed without a baffle. My reasoning was at idle there would be the least amount of pressure from exhaust, compared to 3000 rpm and up, where the EGR system is supposed to kick in.
Strangely though on the pass before that failed, I did have the afm set at 2 clicks. On this run as well I did much more of a warmup, driving around for 30 minutes or so to try to get the cat hot. It is a high flow cat. Even though HC and CO were three times higher than previous passes they are still only 10% of the allowed limit. Very low and I am not concerned about it at all.
I can understand not wanting to replace a $200 valve if you don't have to. But, I bet if you just yank it off every 50k miles and clean it the valve will last forever.
I wonder if there is any long-term danger to running without the EGR. Like you said, Toyota likely designed this as part of a system, they didn't just slap the EGR on there to get through emissions.I've been reading a bit about EGR, and it seems it can actually increase power. It requires the throttle to be slightly more open for a given power output, which can make the throttle operate more efficiently. Also, the reduced cylinder temps can reduce the amount of heat soak happening, increasing efficiency by having more heat go into forward motion rather than absorbed into the cylinder walls. Interesting stuff (to me at least, haha.)
Anyway my butt dyno confirms no ill effects of a functional EGR.
Your exhaust temps were higher before, which could have helped to burn off more HC/CO's, i.e., every action causes an equal but opposite reaction.......
....I can understand not wanting to replace a $200 valve if you don't have to. But, I bet if you just yank it off every 50k miles and clean it the valve will last forever.
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