Emissions!!!!! FAILED!!!

[PorterzSupra]

Heres the deal guys, had to goto Emissions today w temp plates and FAILED!! My car is a 88 turbo with 3 inch from turbo into muffler, advanced timing, Lex A/F and filter, BC to 18 PSI, 550's, BOV. I put oil breathers on the valve covers to eliminate the hoses to the accordian pipe, 12 volt fule pump mod and a few other small things. I went thru with boost turned back down to stock and took out the BOV and even installed a new cat. This next run im planning on retarding the timing, turning the fule pressure way down to like 15 PSI and puttin the stock A/F meter back in. Basically if I lean out the car the guy said it will pass because its running too rich to there system, my A/F meter says its ideal though. What do u guys think??

Any other ideas/comments to help it pass? Attached is the print out of the emissions -- THX Eric

 

[chevyeater]

The HC (unburned fuel) isn't that far out. The CO (partially combusted fuel) is thru the friggin' roof though wich leads me to believe the car just isn't running well.

I'd put the timing back to stock and put a fresh set of stock heat range plugs in (check compression while you are at it), check for codes and repair as nessicary. Also, check for things that may cause the A/F to vary from cylinder to cylinder like maybe a vapor purge sucking liquid gas, a vacuum leak at one of the runners, a bad injector etc.

Last but not least, make sure the cat converter is fully up to temperature before testing.

 

[xarewhyayen]

Excellent advice^^^ :drink1: cheers to u

 

[PorterzSupra]

I know it might sound crazy but I herd from a buncha ppl to run a bottle of grain alki in the tank to make it run cleaner, it dident seem to work..

 

[mrnickleye]

02 sensor is the MAIN fuel mixture input to the computer. Get a new one, today. They are pretty cheap from any parts house ($40-80). Bosch is very common, and work just fine.

HC is high because of the high CO. It will come down.

The NOx is fine now, because it is running sooo....rich. It may come up when your mixture leans back out. Do you still have the egr system?
It controls NOx.

Just set the timing at 10* and you should be ok.


If you leave the CO that high (rich), your cat won't last a year.

(OH yea, btw, I manage a smog test and repair shop here in calif.):love:

 

[daledoe]

That sucks!!! I'm glad that it's not like that up here.

 

[csr ma71]

Check your o2 sensor connectors. Mine were exposed and brittle that caused me to fail one of the tests by 10x the limit. So I hardwired them and barely passed. Plus my throttle response picked up remarkably.

 

[funkymonkeybooze]

Your HC & CO emissions are both sky high (i think I've seen less on a challenger tank!:aigo: ) especially if you have a new catalyst. I'm an R&D engineer from an emissions specialist in the UK.

Your timing is 50% to blame coupled with your lowered boost pressure. The result is poor detonation and rich fuel/air mixture. Keep boost high as this will help the car to burn the excess fuel from those 550's.

Tricking the ECU into thinking it is taking in less air than it actually is, is bad news for emissions, here is the proof. Your ECU needs re-mapping by a specialist (aswell) to account for the changes.

Another point is that the catalyst simply isn't big enough for the job any more. Your car's output is probably twice the standard which means...twice the catalyst volume.

As a last resort put the stock injectors & air mass flow unit back on.

 

[Asterix]

Dayam, you're running rich! HC is not bad, which means you're not burning oil, but definitely, as others have said, lean that puppy back to where it's supposed to be. You'll pass then.

Asterix

 

[huntin5L]

hydrocarbons is unburnt fuel not oil.

 

[7MGTEJoe]

Heres the deal guys, had to goto Emissions today w temp plates and FAILED!! My car is a 88 turbo with 3 inch from turbo into muffler, advanced timing, Lex A/F and filter, BC to 18 PSI, 550's, BOV. I put oil breathers on the valve covers to eliminate the hoses to the accordian pipe, 12 volt fule pump mod and a few other small things. I went thru with boost turned back down to stock and took out the BOV and even installed a new cat. This next run im planning on retarding the timing, turning the fule pressure way down to like 15 PSI and puttin the stock A/F meter back in. Basically if I lean out the car the guy said it will pass because its running too rich to there system, my A/F meter says its ideal though. What do u guys think??

Any other ideas/comments to help it pass? Attached is the print out of the emissions -- THX Eric

Your best bet to pass smog is to reinstall the 440's and the stock AFM. I've never heard of anyone passing smog with the lex/550's. The big trade off with the lex/550's is you run pig rich off boost and your test results indicate that. Don't cut fuel pressure, you need the pressure to aid in fuel atomization.

 

[Demianu27]

here's an idea, go to a gas station that does inspections for like $70!

they are a lot more lienent.

 

[CTsupra]

boost has nothing to do with it :rofl: what? is he going to boost 18 psi on the emissions dyno?

 

[IJ.]

All those $5 mods really kick emissions in the nutz eh!

 

[Asterix]

hydrocarbons is unburnt fuel not oil.

Not always. There's always some oil in the combustion chamber. If your valve guides are leaking, there's even more and will show up as unburned hydrocarbons. Even if you're running lean and all the fuel is burned, HC still shows up. It's from the oil. HC levels can be used as a measure of engine health, especially valve guides and rings.

Asterix