cam69ss

Good Old MA dyno testing gets me

Grams Per Mile
Reading Limit
HC 1.06 2.00
CO 5.86 30.00
NOx 4.17 3.00
CO2 359.26 N/A

Car Details:
1990 300SE 228,000 Miles
Car was running hot little over 100C
Only had mid grad gas in it 89 octane
Car sat idling for 5-10 mins before being tested

Cap, rotor, plugs, wire, filter, EGR valve replace less than 30,000 miles ago
Cat. was replaced back in 96 or so at 70,000 miles

Does the car need a new cat. system?

Or should I retest using premium gas and when it is running cooler and not allowed to idle so long before the test?

I have one more shot before I have to pay another 29 bucks.

Thanks
Dan

howdosaymercede

Thats caused by high combustion chamber temps, I wonder if letting the car sit and cool off then going for the test say if you parked down the street then immediately drove to the station before it was completely warmed up, anyway, my sisters accord was the opposite it would run really rich when she started it up then when she got to the station they would tell her to drive it around and come back and it passed clean, your car may be the opposite way around lol, just a thought....its way below the max on co so if you wanted to richen it up alittle (I don't know how thou) that may bring the temp down but bring the hc up so have to just richen it alittle..., a new cat would probebly do it if its worth it, could use a new cap and rotor and filters thou and would probebly help...

Archie_Valentin

My car sat for about a year and when I took it to get DEQed it failed after passing every other time with flying colors I took it to a shop and the mechanic sprayed some cleaner into my air intake or something like that and it passed bettet than it ever has was an easy fix only costed me 20 for the can of cleaner