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Discussion Starter #1
Or does direct injection eliminate the need for EGR (exhaust gas recirculation) OR is it done via variable exhaust value timing (like the old Zetecs in Ford Escort ZX2s)?
 

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So I just spent some time looking through the service manual and couldn't find anything. A search of EGR and exhaust gas recirculation yielded no results. I also browsed the exhaust system, emissions and evaporative system for good measure but didn't see anything.
 

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For twin cam or DOHC engines, VCT was used on either the intake or exhaust camshaft. (Engines that have VCT on both camshafts are now designated as Ti-VCT.) The use of variable camshaft timing on the exhaust camshaft is for improved emissions, and vehicles with VCT on the exhaust camshaft do not require exhaust gas recirculation (EGR) as retarding the exhaust cam timing achieves the same result.
http://en.wikipedia.org/wiki/Variable_Cam_Timing
 

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Excellent. Thanks for the reference. This is what the Ford Escort ZX2 with the 2.0 Zetec engine had: variable exhaust cam timing.

For some reason, the Focus ZX3's with the 2.0 Zetec did not have variable exhaust cam timing.
Still....way better than the split port junk engine. [:D]
 

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Discussion Starter #7 (Edited)
Still....way better than the split port junk engine. [:D]
I still have 1 remaining SPI in my stable. [:)]

But yeah, the Zetec complete different engine, although I thought they shared or had very similar bottom ends. I may be mistaking.
 

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No EGR. No fuel filter either from what my dealer mechanic told me. Don't know if anyone has seen this video of how the Variable valve/Cam works. It's a 1.6L in the video but the same system as our 2.0L. Pretty fascinating how it works. Mostly all done with oil pressure.Pretty complicated system really. It's surprising it works as good as it does. Or works at all for that matter. Variable valve timing is how our cars can use just about any octane.

https://www.youtube.com/watch?v=eNvD_rRXsww
 

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Discussion Starter #9
Oh shit, don't bring octane into the discussion, you'll get members posting on how the DCT "runs less efficiently" (with no mention of less efficiently than what).
 

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No EGR. No fuel filter either from what my dealer mechanic told me. Don't know if anyone has seen this video of how the Variable valve/Cam works. It's a 1.6L in the video but the same system as our 2.0L. Pretty fascinating how it works. Mostly all done with oil pressure.Pretty complicated system really. It's surprising it works as good as it does. Or works at all for that matter. Variable valve timing is how our cars can use just about any octane.

https://www.youtube.com/watch?v=eNvD_rRXsww
Um.....please tell me our engines have timing CHAINS, not belts.
 

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Discussion Starter #11
Chains indeed.
 

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Don't look at the new small engines out now, belt in the oil bath.
 

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Discussion Starter #15
Don't look at the new small engines out now, belt in the oil bath.
D'oh! But are the belts intended to be changed at specified intervals like dry belts?
 

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Actually not, supposed to have "life of engine" durability matching a good chain system.
 

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Actually not, supposed to have "life of engine" durability matching a good chain system.
I don't plan to be a beta tester for that new technology.

The original rubber belts never seemed like a good idea to me, especially when the one on my wife's Camry spun a few teeth off. (Luckily it had a "non-interference" engine.) At least they were easier to change than chains. They were supposed to be replaced if they got any oil on them, so what you describe has to be some totally different material. I don't care how much testing it has been through, the real world always brings surprises.

Do you know whether the TiVCT 2.0L engines have "a 'good' chain system" with actual "life of engine" durability? What would make it a "bad" chain system? I haven't read any reports of premature failures, at least.

Another thing I do not miss with this engine is EGR. Good riddance. I hated that stuff from the first time I read about it. Cleaning and replacing a few gunked up EGR valves over the years confirmed my original skepticism.
 

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I'm with ya Bro, having memories of cog belts going from 30,000 to 120,000 mile change intervals I'm wondering what that "life of the engine" really will add up to for the new tech..

Chains give up for tensioner problems more often than any other cause, the duratecs didn't have a notable problem there & hopefully the TiVCT version won't either.

EGR systems are generally a PITA, as is anything else 'extra" we'd rather not have to deal with!
 

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EGR systems are generally a PITA, as is anything else 'extra" we'd rather not have to deal with!
Yeah, they generally introduce their own set of problems with time.

People who have been trying to remove it to eliminate recurring problems (e.g. stuck EGR valve) had 50/50 success because of the engines being calibrated for it.
 
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