Reply With QuoteYour tune will be the largest factor contributing to the emissions. What ecu are you using to run it? If you can switch over to e85, that will help massively with emissions.
7age with high hydrocarbon emissions *Sorted*
Car: 1984 Toyota Ae86 GT Coupe
engine: 7age
problem: ok so i built a 7age recently some of you may remember a previous thread i started about it. Well i have been having a lot of problems since i built it. I got the engine eventually running ok, went to get the car tested and it failed the hydrocarbons part of the emissions with a reading of 2970 ppm on the first test and mad 4070ppm on the re test. In ireland the limit is 1200 and i believe a good engine should have a reading of around 600ppm.
so obviously something is badly wrong. I have since stripped the head and found 2 very slightly bent valves, changed these but no change, then sent the head to get checked, he recut the valves then did a test and all valves sealing perfect, ive refitted the head but not built the engine back up.
Ive also done a compression test, 3 readings of 250 and 1 of 245psi, now i assume this is still ok even for a new engine? And shouldnt cause any problems with hydrocarbons?
i am just wondering if there is anything that could be causing hydrocarbons to be this high?
thanks for any input/advice
Last edited by kieran_macca; 12th May 2014 at 12:18 AM.
Your tune will be the largest factor contributing to the emissions. What ecu are you using to run it? If you can switch over to e85, that will help massively with emissions.
4agte finally finished. 252rwkw with more to come
Sorry i forgot to mention im using standard ecu.
i dont want to sound stupid but whats e85?
thanks for the reply
E85, petrol haha. Im currently using 97ron petrol.
E85 is an ethanol blend of fuel that we can use here in Australia, it runs much cooler and can give noticeable gains. I would definitely be looking more into an aftermarket ecu and a tune to suit the 7ag, is the stock ecu that your running for a 4age?
2 catalytic converters help
Ae86 Drivingclub - Toyota AE86 Car Club where AE86 | KE70 | Toyota 86 / GT86 | Subaru BRZ | Scion FRS owners
Without tuneability, you'll find it very hard to get emissions down. Get an aftermarket ecu to get the best out of your motor.
4agte finally finished. 252rwkw with more to come
What injectors are you running, what is the air fuel ratio?
Is the test linear ie. always over or just spikes? Disconnecting the purge valve for the charcoal canister can reduce spikes
Ae86 Drivingclub - Toyota AE86 Car Club where AE86 | KE70 | Toyota 86 / GT86 | Subaru BRZ | Scion FRS owners
I dont think we can get e85 here in ireland so that ideas out the window.
Yea the ecu is for a 4age, the car will drive but it is just down on power. I thought plenty of people ran there 7ages on standard ecu though?
Im running standard grey injectors with fuel pressure up a little, not sure on the exact a/f ratio but adjusting the fuel pressure makes no difference to the hydrocarbons it would appear.
yea its always over, could never get it to come down substantially.
Isnt hydrocarbons unburnt fuel though? As far as i know co2 emissions are more to do with air fuel ratio?
thanks for the help guys
Sorted!
built the engine up and it must have been leaking valves all along. Engine has great power and nice torque, able to drift in 3rd gear now instead of second, faster drifts=happy kieran! Haha
thanks for any input guys much appreciated, next on the list will be some rolling road time for a bit of fine tuning, then when i make a bit more money some itb's, larger cams, and good management
i might try to upload a video at some point if anyones interested!
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