c4 failed CA emmssions

[CorvetteMichelle2004]

my old girl failed don't know why either.

 

[Schrade]

I can tell you why - hydrocarbons too high, oxides of N with room to spare.

Too much fuel which causes too high HC count which causes too low burn temps, which lowers NOx.

Vacuum leak, and/or SES light still on.

Does it lope idle, especially at the stoplight? Have you checked to see what the code(s) are?


Tune it, or take about 3 fifth bottles of Everclear 190 proof, and fill it up after you put in the booze (at the gas station). Ethanol will reduce HC's, increase burn temps, and will raise NOx count (but you have LOTS of room to spare on that).

ed.:
Ethanol added to the gas will not necessarily increase burn temps, unless the squeeze is increased, or unless the timing is advanced, or both. Only if this is done, can we say with certainty that burn temps will increase. Increasing burn temps will increase NOx's

 

[Toms007]

I'd say that a bit more information is needed Michelle. Post the results. I think Schrade has some good suggestions, we just need some better direction.

 

[Hib Halverson]

I can tell you why - hydrocarbons too high, oxides of N with room to spare.

Too much fuel which causes too high HC count which causes too low burn temps, which lowers NOx.

Vacuum leak, and/or SES light still on.

Does it lope idle, especially at the stoplight? Have you checked to see what the code(s) are?


Tune it, or take about 3 fifth bottles of Everclear 190 proof, and fill it up after you put in the booze (at the gas station). Ethanol will reduce HC's, increase burn temps, and will raise NOx count (but you have LOTS of room to spare on that).

Everclear, at 190 proof, is 95% ethanol. The gasoline in California is already 8-10% ethanol. How will increasing the ethanol content improve emissions? Keep in mind that once you get past 10-12% ethanol, the resulting ethanol/gasoline blend may damage a pre-1990's Corvette fuel system.

Also, three times in the last ten years, CARB has lowered the NOx cutoff point attempting to force old cars off the road. How sure are you that the car in question has lots of room to spare?

 

[Schrade]

Everclear, at 190 proof, is 95% ethanol. The gasoline in California is already 8-10% ethanol. How will increasing the ethanol content improve emissions? Keep in mind that once you get past 10-12% ethanol, the resulting ethanol/gasoline blend may damage a pre-1990's Corvette fuel system.

Also, three times in the last ten years, CARB has lowered the NOx cutoff point attempting to force old cars off the road. How sure are you that the car in question has lots of room to spare?

I'm not psychic - so I don't know for sure her NO count is way under the margin (even for that matter, that it's not the opposite - low HC's, and NO's OVER the limit - I've seen that ONE time). But 99% or more of the time, it's the former.

The 'ethanol-fuel system' damage argument doesn't hold much water (pun intended). The argument is that mild acids form from the water in the alcohol. Corrosion of the fuel system components isn't gonna' happen overnight, IF AT ALL. And there's less water in Everclear than in ANY alcohol-fuel blend. Only because in practice, you CAN'T remove all the water from alcohol...

There's no arguing that adding ethanol will decrease HC's. Nor is there an argument that the extra oxygens will increase burn temps, and increase O2's in the pipe (if it's rich, it's low right now on O2 count). The car is DESIGNED to handle E10 10% alcohol, and can probably handle much higher than that (E85?). 3 fifth-bottles of alcohol will increase to only about E15. From there, the difference can be calculated. It's not science for NASA researchers.

That will be easier and cheaper for the person than tuning it. Not the right way, and I wouldn't do it, but that's only because I can tune. How many times have we seen out-of-tune cars never get tuned?

 

[Hib Halverson]

The problem with "E15" in an 89 fuel system is not as much corrosion of metalic parts as it is damage to rubber and plastic parts. Also, even E8-E10 can damage injectors which were made prior to the time blended fuels were introduced.

The fuel system in an 89 was not intended for use with ethanol although it may tolerate E8 or E10.

Explain how gasoline spiked with Everclear to make E15 or E20 is going to change the air fuel ratio. Are you going to also force the system into open loop?

(snip

That will be easier and cheaper for the person than tuning it. Not the right way, and I wouldn't do it, but that's only because I can tune. How many times have we seen out-of-tune cars never get tuned?

You can tune, eh.
I'd be interested in testing some of your tuning work. Have you ever done any LT5 cals? If so, I'd be interested in testing your work.

 

[Schrade]

I have no experience with LT5. Yeah, I CAN tune. AND diagnose. On par with the BEST. And catch errors in FSM - one at least.

Explain how gasoline spiked with Everclear to make E15 or E20 is going to change the air fuel ratio.

The air fuel ratio is not going to change. If the pulsewidth remains constant, more oxygen is going into the fuel - NOT THE ATMOSPHERIC gases, but the fuel. Gasoline is pure alkane. Alcohols have oxygen - I don't remember if they're elemental, or hydroxyl groups, and I'm not googling. THAT's how you're going to get more oxygen into the burn.

If the car is already defaulted to open loop for tune problems, then short of fixing it, alcohol WILL reduce the numbers. There's no argument to that. PERIOD. And no damage is going to occur over night. NONE.





Are you going to also force the system into open loop?

 

[Hib Halverson]

I have no experience with LT5. Yeah, I CAN tune. AND diagnose. On par with the BEST.

Darn. I thought I could try out some of your cal work.

And catch errors in FSM - one at least.

In which year FSM and on what page is the error...I ask so I can mark it in my book

If the car is already defaulted to open loop for tune problems, then short of fixing it, alcohol WILL reduce the numbers. There's no argument to that. PERIOD. And no damage is going to occur over night. NONE.

Just want to make sure I understand you....the Everclear "trick" only works if someone goes through the smog check with the ECM in open loop?

 

[Schrade]

Just want to make sure I understand you....the Everclear "trick" only works if someone goes through the smog check with the ECM in open loop?

Only?

I don't see where I posted that that's the only condition where it will HELP. I don't see where I said it 'works' either.

I said it will reduce HC's, and increase NO's. And depending on how far beyond the limits the OP is, it COULD pass first try.

I hope this a little easier for you to understand...

Perhaps you can offer your own insights on why alcohol / ethanol has been added to gas at all??? (save the global warming argument - I can't go there)

 

[Schrade]

So I did 'google', and found this (which could also be wrong).

For post-1985 fuel-injected engines, all the components are already designed to accommodate E10

and this:

Operation on up to 20% ethanol is generally considered safe for all post-1988 cars and trucks.

That seems to contradict what you said. Which is right, I'm not totally sure (although I AM sure damage will not occur overnight).

The fuel system in an 89 was not intended for use with ethanol although it may tolerate E8 or E10.

So maybe you can clarify here?

In which year FSM and on what page is the error...I ask so I can mark it in my book

Here, I think you're only being facetious. But if I'm wrong, and you genuinely want to know the error, it's a wire color coding error in the headlight wiring schematic of '94. It's posted, with scan and pics in a reference sticky, and here in CAC as well, IIRC.

 

[Hib Halverson]

"Schrade"
Ethanol blended fuel was not widely available prior to 1990, so the early Bosch and ACD injectors are not compatible. Run E10 through them and they will fail but, I agree, not overnight after on one tank of fuel but they will fail.

Your Google results--not specified--are either only partially accurate or inaccurate.

If you run E8-10 in a pre-90s car, you'll eventually have to change the injectors. If you run more ethanol than that, you'll replace other parts, too.

I'm sorry that you think my interest in your error finding is disingenuous but thanks for the answer. I'll note that in my 94 FSM. Got any others? If have FSM from 82-09 and I like to correct any errors that I or others find.

The bottom line on this thread is that the Everclear trick is pretty dumb. The best way to pass the smog check is to service the engine controls to fix the problem which is causing the failure.

 

[93Rubie]

The car is DESIGNED to handle E10 10% alcohol, and can probably handle much higher than that (E85?).

Fill up ANY non Flex Fuel car with E85, and see what happens. You WILL have a check engine light, fuel trims maxed out. I've seen it first hand.
Stoicometric for Ethanol is 8:1 far from that of gasoline at 14.7:1.

E10 will not effect most cars to much, even older ones. Can cause problems over time, key word is can, not will. There was talk of the Federal Government requiring more ethanol in the gasoline. Bad idea, even my 01 Focus would not like that much less my 93 Corvette.

Ethanol is the biggest joke since Richard Nixon or Jimmy Carter, and as big a scam as global warming, but that is a discussion for another time.

 

[93Rubie]

"Schrade"
Ethanol blended fuel was not widely available prior to 1990, so the early Bosch and ACD injectors are not compatible. Run E10 through them and they will fail but, I agree, not overnight after on one tank of fuel but they will fail.

Your Google results--not specified--are either only partially accurate or inaccurate.

If you run E8-10 in a pre-90s car, you'll eventually have to change the injectors. If you run more ethanol than that, you'll replace other parts, too.

I'm sorry that you think my interest in your error finding is disingenuous but thanks for the answer. I'll note that in my 94 FSM. Got any others? If have FSM from 82-09 and I like to correct any errors that I or others find.

The bottom line on this thread is that the Everclear trick is pretty dumb. The best way to pass the smog check is to service the engine controls to fix the problem which is causing the failure.

I agree, that or move the heck out of California. Visual only in my county of PA. My car does have functional cats, no lie. I need them to muffle the sound.

 

[vetteboy86]

my old girl failed don't know why either.

Hi There,

Did you get a report that detailed the test and how the car performed?

 

[Schrade]

I do hope OP is still logged on here...

I qualified the first response with 'tuning the car'. We all know how often THAT happens. OP can't do it, and mechanics will take all their money and not do it either. We see THAT all the time too. What's left? My solution. That's the whole point of introducing it in the first place.

And we didn't suggest moving up to E85 strength either - you've got to READ. And think.

The google results are wiki items. Like I said, they could be right or wrong. But it's 3rd party info, with no vested interest in the smog discussion, so it can't be ignored. I think end-users can edit wiki stuff (or challenge it), so have at it.

And we're presuming that since it's out of tune, it's ALREADY defaulted to open loop with pulsewidth max'ed.

Alcohol gas IS a joke - a bad one. But all it takes is a little intuition to see how to use the 'enemy' to your benefit. That's how they work in DC.

 

[Hib Halverson]

(snip)

The google results are wiki items. Like I said, they could be right or wrong. But it's 3rd party info, with no vested interest in the smog discussion, so it can't be ignored. I think end-users can edit wiki stuff (or challenge it), so have at it.

Perhaps, not too credible

And we're presuming that since it's out of tune, it's ALREADY defaulted to open loop with pulsewidth max'ed.

If that was the case, the MIL would be on. The OP did not report that, but...he didn't report much of any symptoms. Maybe it'd be best to shelve this discussion until the OP gives us more info about why the car failed and in what condition the engine controls and the engine are in.

 

[LLC5]

And we're presuming that since it's out of tune, it's ALREADY defaulted to open loop with pulsewidth max'ed.

Open loop does not mean that the injector pulse width is maxed out.

 

[Schrade]

Open loop does not mean that the injector pulse width is maxed out.

Another politician... All they have to say is, "His plan doesn't work".

Know why they don't tell you about their own plan? Cause it doesn't work either.

Tell me what 'IS'; don't tell me what is 'NOT'.

Any other politician wants to make some more noise?

 

[vetteboy86]

Any other politician wants to make some more noise?

Not in C4 Tech and Performance.

There's good information in this thread. Let's hope the original poster will respond with more detail.

 

[Z51JEFF]

Just ya just love it when somebody has a problem,asks a question and ya never hear from them again?How that for gratitude.