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Discussion Starter · #1 ·
Okay since we have emissions testing here... and it's been awhile since i sent my '91 through the testing.. got a CEL during the test (EEKS!) the driving test (`driving' at like 25MPH) went pretty well

Hydrocarbons (PPM) was 30 (87 is the cut off)
Carbon monoxide (%) was 0.3 (.59 is the cut off)
Oxide of Nitrogen (PPM) was 60 (878 is the cut off)

Sadly the idle test was where it failed, BADLY!

Hydrocrabons (PPM) was 844 (82 cut off)
Carbon Monoxide (%) was 4.53 (.5 cut off)

I had a CEL a few time in route to the testing place.. so i'm guess it was in `limp mode' or something.. so would that explain the crapy idle specs but not the Driving??

Also the Codes thrown where 172 and 332.. Found the EGR valve itself was `frozen' but at full engine Vaccum it `popped' free... why it didn't well driving down the road... unless the siliniod varies the vaccum??

Also how does the EEC-IV determine if code 332 is needed?? Is it when the EGR doesn't move or ??

Also how does one test the EGR siliniod on the firewall?? Just `short' out a terminal (which ever does to the EEC??)

AND should the vacuum line at the EGR surpose to be `pulsing'?? sorry do not have my Vaccum guage on me to see what kinda a vaccum it's pulsing at..

thanks in advance...
 

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I wouldn't be worried about the EGR so much. EGR only effects NOX, and only while driving. Your test was fine while driving, and NOX is way down, so your EGR is working as far as the test goes. The high HC and CO means that your car is running very rich at idle, but without looking the car over, I'm not sure why that is. You should probably start with all the basic tune-up stuff, plugs, O2 sensors, clean MAF, and maybe some top engine cleaner/fuel injector cleaner or something like that. Also you could try bumping up the idle a bit to see if that brings the HC and CO back to passable limits.

Mike
 

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Discussion Starter · #3 ·
Well the EGR wasn't working.. it was frozen shut.. after removing the EGR valve, cleaning it up abit (not as easy as on my 89) slapping it back on.. i didn't get a CEL for a whole of like 10-12 miles then it came back on, but went off soon after.. and it kept doing that for like the 2 1/2 hour drive i took... got home, scaned and just got the 172 code.. (Lean bank 1)

Also i know the car needs MINIUM a cap and rotor.. the MISS it had before i cleaned them was NASTY!! it was even slightly noticeable in 1st gear (5spd)
Also i had issues getting the O2 sensor out of my `off road' Y-pipe and needed to use a propane torch to warm up the bong to get it to come loose (and i was using a O2 socket) so MAYBE something got screwed..

Well i'm gonna least get a O2 sensor and a cap and rotor for it.. and see if that does anything...

Thanks
 

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complete tune up,
plugs wires cap /rotor fuel air pcv and pcv filter
new o2s
clean maf
and before you do all that , seafoam!
 

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Like I said, when you went through the emissions test, your EGR was working. Maybe it wasn't working before then, or maybe it stopped working afterwards, but at the time of the test it was working perfectly. It is possible to pass a NOX test without EGR, but just barely. The only way to get a reading that low is if the EGR is working. If it were my car, I would do like jk89 says. You have a rich misfire at idle. Just because the O2 sensor says lean doesn't mean it actually is lean. O2 sensor can only read oxygen, not fuel, so if your engine takes a big gulp of air and fuel mixture, then doesn't burn it and sends it out the exhaust past the O2 sensor, it will only see the oxygen and tell the computer you are running way lean, and then the computer will add fuel which will only make your rich misfire worse. Deal with that problem first, then worry about the EGR if you fail for NOX when you go back the next time.

Mike
 

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Discussion Starter · #6 ·
Well with an Error code of 332, before and after the test i would think the EGR system wasn't working..

Well today i just got myself a O2 sensor and a cap and rotor, cleared the EEC (IE yanked fuse G) and went to have it tested again.. this time it passed the idle test

once again Driving test was (same cut offs, duh)

HC was 7 PPM
CO was 001%
NOx was 76 PPM

Idle test

HC was 38PPM
CO was 017%

Funny how the NOx went up when the EGR valve was working.. :confused:

NOW i need to get it insured, figure out why the left channel of the stereo keeps cutting out, and it'll be good enough to go :)
 
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