In my quest to make my Prius run better I've got access to a Horiba MEXA-584L at work. It may help me partly diagnose the combustion (or not) but I'm interested to have a go either way. For those of you not in the UK, emissions testing is part of the MOT (annual car safety) test, but I didn't get a printout with the recent MOT (the car passed with no advisories, EVEN with my spark plugs not tightened up properly). Maybe the Prius is exempt from the emissions test, I don't know. But hey, guess what I'm doing it anyway, out of curiosity. I'm just like that. So does anyone know the what the exhaust levels for HC, NO, CO, CO2, should be for a Gen 3 2011 UK spec Prius. I can grab the Engine Speed off my OBD2 reader. And I think the machine works out the Lamda and O2? Other than that, does anyone know what the procedure is to measure these levels accurately as if I'm doing the emissions test for an MOT or at the Toyota garage. I know you need to warm the engine up, and then do something like the engine at certain speed for a certain amount of time, etc. I guess this is done in maintenance mode. If anyone that does this kind of thing daily or someone with some experience of MOT testing in the UK could chime in I'd be quite happy. Thanks
I don't know that brand of machine It's been years since I've actually had to have a car probed at an inspection station they don't generally do that anymore in the States they just connect up to the OBD2 connector and read off the car sensors hence why you can't have a check engine light on generally speaking so there's always that when I lived in Western Massachusetts and they had to do this regularly they had this long gooseneck wand with a probe on the end of it and a wire coming out the end of the handle that they would boot the machine or wake up the machine press some buttons never really paid much attention they'd have the car up on the lift but only about waist high they would shove this probe up the tailpipe and usually somebody would be sitting in the car and the machine would tell the screen watcher what it needed to have happen at some point they'd have to have the car $1,500 to 2000 RPM some guy from the Amoco commercial sitting in the seat stepping on the gas is what you usually got so many seconds so on and so forth the bar graph goes across the screen Guy yells at the guy in the car and tells him to get off the gas everything sits there at idle while the machine registered numbers spits out some percentages of the stuff there analyzer is looking at back in the old days it didn't even get printed out The screen went green said you passed they wrote the number down or something. Still had to manually peel and inspection sticker to its tape and literally put it in the window. But people in the shop didn't care what the numbers were they just care that they saw green on the display when the test was finished and that meant a sticker could be issued to that car or that VIN number let's say that's an important thing. So people were sniffing cars and sticking the sticker on another vehicle A lot of that went on It used to be on your veccie sticker under the hood. It gave you some percentages of hydrocarbon and CO and what have you generally if you fell into those ranges of the two numbers or whatever you were good to go My old Corollas and Toyota celicas and supras would pass the sniff test and see the right numbers with gutted catalytic converters oil burning going on on the 22REC engines so on and so forth so the numbers must be way off on purpose for the government test so that pretty much well almost anything can pass it seemed like. At the time anyway.
It's pretty much the same here. Only want to do it since the Toyota Tech site shows what the HC and CO, etc should be for a healthy engine and what the symptoms could be if the values are too high or low. We have a Horiba MEXA-584L here. It seems easy enough. The emission limits for the UK are here: MOT inspection manual: cars and passenger vehicles - 8. Nuisance - Guidance - GOV.UK (www.gov.uk)
