|
|
|
#1
|
|||
|
|||
Close, but No Cigar
I decided to take one more shot at the test before turning it over to Herr Fuchs. And it almost worked.
The Mobil station got their tester working, so I went back for the idle/2500 RPM test. I replaced the cap, rotor and plug wires to try to fix the HC problem. Results Limit/Test Idle 2500 HC ppm 220/376 Fail 220/113 Pass CO% 1.20/.21 Pass 1.20/.35 Pass This is a huge improvement over the first test. I think what I am getting is a "lean idle missfire" So the fix may be to richen the mixture a bit to smooth out the idle since I have lots to spare in CO. But I'm gonna let Herr Fuchs make that ajustment tomorrow.
__________________
Chuck Taylor Falls Church VA '66 200, '66 230SL, '96 SL500. Sold: '81 380SL, '86 300E, '72 250C, '95 C220, 3 '84 280SL's '90 420SEL, '72 280SE, '73 280C, '78 280SE, '70 280SL, '77 450SL, '85 380SL, '87 560SL, '85 380SL, '72 350SL, '96 S500 Coupe |
#2
|
|||
|
|||
Which car does your post refer to ?
|
#3
|
||||
|
||||
The Wandering Woman (380 SL), of course.
__________________
Mike Tangas '73 280SEL 4.5 (9/72)- RIP Only 8,173 units built from 5/71 thru 11/72 '02 CLK320 Cabriolet - wifey's mid-life crisis 2012 VW Jetta Sportwagon TDI...at least its a diesel Non illegitemae carborundum. |
#4
|
||||
|
||||
leathermang: Screwed Again by Wayward Woman!
Chuck: I don't see how richening the idle would fix it. HC's are unburned fuel usually resulting from rich mixture. If you have more oxygen, then the leftover HC's (IE: C3H6) would burn into CO2 and H2O.
__________________
Current: 2021 Charger Scat Pack Widebody "Sinabee" 2018 Durango R/T Previous: 1972 280SE 4.5 2014 Jeep Grand Cherokee Limited "Hefe", 1992 Jeep Cherokee Laredo "Jeepy", 2006 Charger R/T "Hemi" 1999 Chrysler 300M - RIP @ 221k |
#5
|
|||
|
|||
You can't richen (or lean) just the idle.
The theory is that is it a misfire caused by a lean mix that produces the unburned hydrocarbons. Bring the mixture up a bit to eliminate the misfire, but not so much as to go over the CO limit. In its 15/25 mph dyno test, it had high NOx which is a sign of a lean mix. Either that or a bad injector. In either case, its time to turn it over to someone who does this for a living.
__________________
Chuck Taylor Falls Church VA '66 200, '66 230SL, '96 SL500. Sold: '81 380SL, '86 300E, '72 250C, '95 C220, 3 '84 280SL's '90 420SEL, '72 280SE, '73 280C, '78 280SE, '70 280SL, '77 450SL, '85 380SL, '87 560SL, '85 380SL, '72 350SL, '96 S500 Coupe |
#6
|
|||
|
|||
Over-advanced ignition timing can also cause high HC and NO readings.
Happy Motoring, Mark
__________________
DrDKW |
#7
|
|||
|
|||
Always do an oil and air filter change before taking it in for the test. New oil should reduce the HC. I've had vehicles go from fail to pass just with an oil change.
__________________
1977 300d 70k--sold 08 1985 300TD 185k+ 1984 307d 126k--sold 8/03 1985 409d 65k--sold 06 1984 300SD 315k--daughter's car 1979 300SD 122k--sold 2/11 1999 Fuso FG Expedition Camper 1993 GMC Sierra 6.5 TD 4x4 1982 Bluebird Wanderlodge CAT 3208--Sold 2/13 |
#8
|
|||
|
|||
Recently Shared your challenge
I failed recent emmissions test with similar "Lean Misfire" problem on my w 114.
The end result was traced to a faulty vaccum hose to the power brake booster. Aprox $ 45.00 part from dealer CND Hope this helps. Gary |
#9
|
|||
|
|||
Tomguy, Thanks for the thread reference... However, I have read it several times and do not think he said in it which of his gassers he was referring to ......but I do see that this is a continuation of that thought.... You guys must just be claravoyant... and better spellers than I ...
|
#10
|
||||
|
||||
leathermang: Whether or not I have a 6th sense is debatable... but the thread I linked was in relation to this one: Anyone Know about Lambda Control?
He clearly refers to his 380SL as the wayward woman
__________________
Current: 2021 Charger Scat Pack Widebody "Sinabee" 2018 Durango R/T Previous: 1972 280SE 4.5 2014 Jeep Grand Cherokee Limited "Hefe", 1992 Jeep Cherokee Laredo "Jeepy", 2006 Charger R/T "Hemi" 1999 Chrysler 300M - RIP @ 221k |
#11
|
|||
|
|||
Why did you send me to thread 54204 ? That is the one in the other post you listed... Just messing with my mind ? .. It can not stand much of that.... being weakened by diesel fumes and all...
Seems reasonable that when a new thread is started which is clearly a continuation of another... that stating in the initial post what is being talked about would be a clarifying move....NO? |
#12
|
|||
|
|||
Thanks for the suggestion, but testing the brakes for a vacuum leak was done a while ago. No difference in vacuum with the hose disconnected and plugged.
__________________
Chuck Taylor Falls Church VA '66 200, '66 230SL, '96 SL500. Sold: '81 380SL, '86 300E, '72 250C, '95 C220, 3 '84 280SL's '90 420SEL, '72 280SE, '73 280C, '78 280SE, '70 280SL, '77 450SL, '85 380SL, '87 560SL, '85 380SL, '72 350SL, '96 S500 Coupe |
Bookmarks |
Thread Tools | |
Display Modes | |
|
|