Drive cycles for emissions
- Thread starter Sho
- Start date
When you say tweak, you mean tweak your tune to make it pass?
If need be. Specifically referring to my EGR I made a contraption that mimics the pressure on the valve, making it believe it is attached to the car. I had to read the values from the app to get the right pressure on the valve. Now that I don`t even have EGR provisions in the manifold all I have to do is plug in the egr valve and let it hang there. The ecu thinks it`s plugged in and working, passes inspection, then back to non dangling egr.
Can you tell us more about the egr pressure? What port?. Mines up in April and can only have 1 not ready.....
I have a egr delete and a catless dp so im fucked until i figure something out. I would rather a egr fix over dicking around with my o2's and extenders.
On a side note this is the drive cycle i used to get my evap and (when i had a oem dp) my cat and o2 monitors ready in 1 day last time.
I have a egr delete and a catless dp so im fucked until i figure something out. I would rather a egr fix over dicking around with my o2's and extenders.
On a side note this is the drive cycle i used to get my evap and (when i had a oem dp) my cat and o2 monitors ready in 1 day last time.
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Sounds like a clever hack you got there
It`s nowhere near as fancy as it sounds. I just had to figure out exactly what the EGR valve does, mechanically, in order to produce its readings. Then I just fashioned up a dummy load on the valve and trial end error led me to being able to mimic the load it sees in the proper range while it`s bolted to the manifold. Nothing more than a piece of vacuum hose stuffed inside another section of heater hose then stuffed into the EGR valve itself. I`ll post a pic of it later.
So what your saying is the egr detects flow (p0401) based on the pressure differance of intake mani vacume vs the exhaust due to force exerted on the egr valve face and not a drop in vacume reported by the map sensor?
I was under the impression egr flow was calculated by the drop in manafold vacume when the valve opens vs when it was closed.
So when the egr tube is clogged the intake mani vac dosent drop as much due to the restriction and it throws a code. Kind of like how the comp throws extra fuel in the motor just to see if the o2's are working right.
If the flow was measured by the force on the valve face from the inrush of air that would be awesome! Please share your wisdom!!!
I was under the impression egr flow was calculated by the drop in manafold vacume when the valve opens vs when it was closed.
So when the egr tube is clogged the intake mani vac dosent drop as much due to the restriction and it throws a code. Kind of like how the comp throws extra fuel in the motor just to see if the o2's are working right.
If the flow was measured by the force on the valve face from the inrush of air that would be awesome! Please share your wisdom!!!
Yeah, it`s a 100% mechanical response. My EGR valve wasn`t even bolted to the engine when it passed. Best I could determine is that there is a current feedback circuit that tells the ECU how much current it took to open the valve. There is no actual flow sensor at all, only a very simple motor driven worm gear.
Ok a pic would be great. Also what size tubeing did you use? Ill assume it goes in the lower port?
KiwiFlavor
Greenie N00B Member
I think @alexwlwsn rigged something up to pass emission.
I just put my EGR back in and fudged it to connect into my fitting for the catch can on the JMF mani. Basically, I cut the EGR tube, attached it to some -10 line (fits perfectly) and T'd it into that line. Also, I used a spark plug defowler on my secondary O2 sensor just in case. In MD you're allowed to have 2 unready codes related to emissions I believe and those were the easiest things for me to just toss in quick. My memory is a little rusty but I guess the VTCS would've taken up both of those.
This is exactly how it was just hanging out in the engine bay, plugged in but not mounted to anything. Don`t know the sizes of the tubing, looks like maybe 1/2" ID and 1/4" ID, reference the pic for fit. I used to Torque app to monitor readiness and once I got this combination it went to ready mode and stayed there for several days until I unplugged it. 
Briliant @VoodooJef
I am Defintaly going to try this. All Parameters need to be “Ready” to pass emissions in CA. I have 362 days to get ready.
I am Defintaly going to try this. All Parameters need to be “Ready” to pass emissions in CA. I have 362 days to get ready.
Awesome im going to try this next week! My ultragauge has a readyness monitor page. Cant believe it took 12 years for someone to post a egr trick as handy as the vtcs relay one.
Whats especially helpful is if your device gives you the range the sensor is expecting and what it is reading. That`s how I got the load right with the tubing. I could see how different setups would affect the measured voltage and then I just had to figure out how to slowly work the resistance up until it stayed in range
Yea so i ziptied the egr to the brake booster hose and jammed some random piece of fuel line in it then went for a drive and it came ready..... I have yet to see if it stays ready or needs adjusting but yea sweet.
KiwiFlavor
Greenie N00B Member
I'm so glad I stumbled across this. Great idea!