fails emissions

[seanc77339]

I have an 87 flatbody conquest that keeps failing emissions testing in the state of Texas. It is not burning off fuel and causing high numbers to appear on the test results.

 

I recently bought high performance injectors for the car because one of my injectors on the car was reading 0.0 on an OHM tester. Have replaced the air/fuel sensor, the coolant sensor, injector clips, checked all the vacuum hoses and running the original stock exhaust system. The cats are not clogged. Took off the system and checked the cats.

 

The car with the 0.0 Ohm reading injector would bog down badly on acceleration. It would pretty much not accelerate at all but creep up instead to the speed I needed.

 

I dropped the brand new injectors in and started the car up. It ran fine and sounded good. Took it down the street about a 5 minute drive and it was pulling and accelerating like a brand new engine and turned around to come back home thinking I had fixed the problem and it started bogging on acceleration again. Now it is bogging yet again.

 

Does anyone have an idea of what could be causing this to happen?

 

Thanks for all the help,

Sean

[Scotty Dont]

What has been done to the car?

 

I would start by going on starquestgarage.com in the service manuals and go threw your vacuum lines making sure they are routed properly and not cracked or split. Next would be to do a boost leak test (search google for a how-to)

[scott87star]

What is causing the emissions fail, CO, HC or NOX? 0 ohms would be a dead injector, might be worth checking the new ones now as well.

 

I'm down by JSC by the way. Do you know Donnie Hardy in La Porte?

 

Scott

[seanc77339]

I put on an intercooler from a wrecked 1989 conquest and hard pipes attached to it...that is the only Modification I have done to the car. The rest is stock.

 

Yes...Donnie and I ran into each other back a year ago. He and I chat and he told me to ask you guys because like me...he has no idea.

 

 

Failed Emission Readings

at 25mph

 

HC (PPM) 244 Failed

O2 (%) 9.99 Failed

CO2 (%) 10.7

NOX 86 Passed

 

at 15mph

 

HC (PPM) 240 Failed

O2 (%) 9.99 Failed

Co2 (%) 10.7

Nox 54 Passed

 

Standard

 

HC(PPM) around 160 for both high and low speed

O2 (%) around 1.00

NOX high- 1121 low-1227

 

[MikeMeyerhoff]

Specifically what injectors did you put in it?

[seanc77339]

Specifically what injectors did you put in it?

 

 

Bought them from Lower Shores Performance (Just named dropped)

 

A BRAND NEW SET OF DIRECT FIT STOCK REPLACEMENT DELPHI FUEL INJECTORS FOR AN 87-89 MITSUBISHI STARION / CHRYSLER CONQUEST!!!

 

- 650cc Primary

- 950cc Secondary

[Bag-O-Chips]

As far as the HC count goes, the car needs to be leaned out a bit. it's just a Tad too rich. You can get around that by messing with the Un metered area on the maf. If memory serves me correct, If you decrease the amount of air being ingested by the engine you can lower your fuel need over all. And if that doesn't work. Lower your fuel pressure just for that day.

 

Guidelines are: HC=fuel unburnt - O2 = Air unused in combustion process

 

When HC's go up, O2's go down = rich condition

When HC's go down, O2's go up = Lean condition

when Nox (nitrates of oxygen)too high = EGR is not working.

 

What EGR really does is re-introduces burnt/inert gas back into the combustion chamber acting as a buffer to pre-ignition/detonation {more or less a safety}and to cool the combustion chamber. 800 degree temps are cooler than 1100 degrees any day.

 

I hope this made some sense. I'll be more than willing to help out any way I can.

 

-Chips

[Metric-man]

As far as the HC count goes, the car needs to be leaned out a bit. it's just a Tad too rich. You can get around that by messing with the Un metered area on the maf. If memory serves me correct, If you decrease the amount of air being ingested by the engine you can lower your fuel need over all. And if that doesn't work. Lower your fuel pressure just for that day.

 

Guidelines are: HC=fuel unburnt - O2 = Air unused in combustion process

 

When HC's go up, O2's go down = rich condition

When HC's go down, O2's go up = Lean condition

when Nox (nitrates of oxygen)too high = EGR is not working.

 

What EGR really does is re-introduces burnt/inert gas back into the combustion chamber acting as a buffer to pre-ignition/detonation {more or less a safety}and to cool the combustion chamber. 800 degree temps are cooler than 1100 degrees any day.

 

I hope this made some sense. I'll be more than willing to help out any way I can.

 

-Chips

That is a good way to display it, but imho

EGR's are crap

they hurt combustion/mileage because HC's, displace oxygen , HC's are also higher temps.

 

The secondary air pipe is a cleaner solution but people don't like the box over the valve cover,

or it's pipe that runs after the turbo before the pre-cat.

(OEM equip that adds air top the exhaust to help dilute exhaust,and lower NOx emissions (temps))

 

 

as for the performance problem

 

If you have not replaced your fuel filters and removed and or replaced the inline filters I would suspect fuel delivery

you might have dirt/ moisture in the system/ tank, and clogging your new injector ??

( pinch the return line ? I think is the test for the return system)

Edited November 1, 2010 by starion_cult

[Bag-O-Chips]

That is a good way to display it, but imho

EGR's are crap

they hurt combustion/mileage because HC's, displace oxygen , HC's are also higher temps.

 

The secondary air pipe is a cleaner solution but people don't like the box over the valve cover,

or it's pipe that runs after the turbo before the pre-cat.

(OEM equip that adds air top the exhaust to help dilute exhaust,and lower NOx emissions (temps))

 

[/b]

 

The secondary A.I.R pipe is there just to speed up the catalyzing process or to get the Catalyst to working temperature @ 600 degrees. Hence the 1 way check valve only allowing air into the catalyitic converter and is controlled through the Thermal vacuum switching valve on the thermostat housing. Once the thermovalve has seem normal operating temperature it closes the signal on the secondary air box. Air Injection Reaction is the correct term for it. And Nox is only a factor when exhaust temperatures are over 1200 degrees.

 

Just for knowledge's sake, EGR's only work during cruising and deceleration. NEVER at WOT, and Has no negative effect on combustion or mileage at WOT. It is only there to act as a damper to pre-ignition from bad ignition components or low fuel quality during low load (cruising/decel) situatons.

 

excess HC's (hydrocarbons / raw fuel) are commonly related for low combustion temps.

excess O2's (oxygen / air) is related to lean conditions and high combustion temps.

CO (carbon monoxide) is a byproduct of combustion

 

Catalysts covert

O2 to h2o - steam

C0 to C02 - Carbon dioxide

 

-Chips

[Metric-man]

The secondary A.I.R pipe is there just to speed up the catalyzing process or to get the Catalyst to working temperature @ 600 degrees. Hence the 1 way check valve only allowing air into the catalyitic converter and is controlled through the Thermal vacuum switching valve on the thermostat housing. Once the thermovalve has seem normal operating temperature it closes the signal on the secondary air box. Air Injection Reaction is the correct term for it. And Nox is only a factor when exhaust temperatures are over 1200 degrees.

 

Just for knowledge's sake, EGR's only work during cruising and deceleration. NEVER at WOT, and Has no negative effect on combustion or mileage at WOT. It is only there to act as a damper to pre-ignition from bad ignition components or low fuel quality during low load (cruising/decel) situatons.

 

excess HC's (hydrocarbons / raw fuel) are commonly related for low combustion temps.

excess O2's (oxygen / air) is related to lean conditions and high combustion temps.

CO (carbon monoxide) is a byproduct of combustion

 

Catalysts covert

O2 to h2o - steam

C0 to C02 - Carbon dioxide

 

-Chips

 

The secondary air solenoid valve also opens at rapid deceleration above 2000 rpm.

 

the term Air Injection Reaction is a trademarked term for General Motors

Chrysler's term was Pulse Air

 

sorry you can read all you want but you can not tell me that "inert gas" as you put it will help combustion an hence fuel efficiency.

It's is sort of like saying turbocharged vehicles are fuel efficient,

 

yeah efficient at burning fuel

Edited November 1, 2010 by starion_cult

[Bag-O-Chips]

Inert gas is inert gas... point is it can't be burnt. Would you rather have a detonating fuel efficient motor, or a NOT detonating motor that runs 2 MPG less that it's supposed to? I believe an engine cost more than a gallon of fuel.

[Metric-man]

Inert gas is inert gas... point is it can't be burnt. Would you rather have a detonating fuel efficient motor, or a NOT detonating motor that runs 2 MPG less that it's supposed to? I believe an engine cost more than a gallon of fuel.

I see Your point being you can't have performance and economy without sacrifice and be smog legal.

 

My 2cents = EGR is not a perfect solution. it's crap.

I'd like to add if seanc77339 has not tested his car for trouble codes he should.

Edited November 1, 2010 by starion_cult

[seanc77339]

I have not checked my error codes yet. That is my next option to fixing this problem. What is the best way of doing this starion_cult?

 

The fuel pump and all fuel filters were replaced a year ago when the pump failed.

 

 

I am confused...

I am presenting High CO and high O2

 

yet by theory:

 

When HC's go up, O2's go down = rich condition

When HC's go down, O2's go up = Lean condition

when Nox (nitrates of oxygen)too high = EGR is not working.

 

So am I experiencing a conundrum??

 

Bag o chips-How does one decrease O2 intake into the engine??

 

 

Thanks again

[Bag-O-Chips]

this document may help you understand how the 4-5 gasses work

 

http://www.autoshop101.com/forms/h56.pdf

 

High HC and CO at the same time is commonly associated with a "Rich condition & Ignition Misfire"

 

Oh and to answer your question about decreasing O2 intake in the engine, the Unmetered area with the BIG phillips head adjuster at the top of the air can is set to a certain amount of air to by pass the MAF sensor. Turning it in reduces the amount of unmetered air coming into the engine thus richening up the mixture slightly. Our ECU's aren't smart enough to actively change or compensate fuel trims like newer cars. It just looks up a value on a table based on load, temps, and feedback.

 

I hope this further helps you out.

 

-Chips

[Metric-man]

I have not checked my error codes yet. That is my next option to fixing this problem. What is the best way of doing this starion_cult?

...

Thanks again

being your cars an 87 your test connector should be behind the glove box,

http://www.starquestclub.com/forum/index.php?showtopic=28043

 

some things to remember

a #3 air flow sensor error can be a false and instead be a #5 TPS error code ,

(but not vise versa)

 

Have you tried switching connector plugs on the injectors..?

 

you have checked the integrity of your inter-cooler and hard pipes no leaks ??

 

 

I've been brushing up on my reading and found in a training guide from Chrysler under General Diagnosis tips...

 

When considering these out of specification conditions, it s possible that a failed coolant sensor circuit could cause readings on other circuits to be incorrect. Repair the coolant sensor circuit or replace the coolant sensor, then retest the system. It is likely that all other items will now function properly.

the phrase "out of specifications conditions" is referring to parameter test voltages of sensors.

 

 

I forgot to add a simple test for the coolant sensor

(itself not the harness)

is to disconnect it at the sensor go for a drive

an see if there is an improvement.

Edited June 21, 2010 by starion_cult

[Bag-O-Chips]

What size is the OEM primary injector (factory equiped) to begin with?

[SFBMX88]

 

Failed Emission Readings

at 25mph

 

HC (PPM) 244 Failed

O2 (%) 9.99 Failed

CO2 (%) 10.7

NOX 86 Passed

 

at 15mph

 

HC (PPM) 240 Failed

O2 (%) 9.99 Failed

Co2 (%) 10.7

Nox 54 Passed

 

Standard

 

HC(PPM) around 160 for both high and low speed

O2 (%) around 1.00

NOX high- 1121 low-1227

 

 

 

So O2(oxygen) is at 9.99%? Do they measure CO(carbon monoxide) where you are? I dont see why it would fail for high oxygen. High CO makes more sense for a failure. Also, do the 87 flatties run staged injectors like the 87 and up widebodies?

[Metric-man]

So O2(oxygen) is at 9.99%? Do they measure CO(carbon monoxide) where you are? I dont see why it would fail for high oxygen. High CO makes more sense for a failure. Also, do the 87 flatties run staged injectors like the 87 and up widebodies?

 

You right seanc77339 has more than one problem,

 

Because I was focusing on his drivability problems, I missed the emission test conclusions.

 

1987 flatbody's are the change over year for injector sequencing

the month a date of production are very important anything before (June) 6/86 and you have an 1986 vehicle,

if his car is a (May) 5/87 or before he has a 1987 vehicle, and typically 1987 have seen some injector cc ratings differ between vehicles who date of production is only a month apart.

If seanc77339 is not the original owner he may have a swapped ECU, from a 1986 or was given a 1987 that had been swapped with 1988/89 internals..

(I personally bought one on e-Bay that way, purely by accident.)

 

The exhaust system that is stock is it ? Is it the original one that came with the car ?

If it is, the catalytic converters are probably not performing to the level of their intended performance, and therefore the description of a catalytic converter being clogged is not literal, but a better description would be contaminated or worn out the chemical exchange of the CATs have failed because it's elemental properties have been compromised by either age or contamination not just by oil or fuel but perhaps coolant at one time, the same for the o2 sensor it could be worn out or contaminated.

What I also failed to convey in was Bag-0-Chips interpretation was right.

 

Guidelines are: HC=fuel unburnt - O2 = Air unused in combustion process

 

When HC's go up, O2's go down = rich condition

When HC's go down, O2's go up = Lean condition

when Nox (nitrates of oxygen)too high = EGR is not working

 

A more accurate description would be :

 

When HC's go up, O2's go down = Rich condition

When HC's go down, O2's & NOx (nitrates of oxygen) go up = Lean condition

 

I got caught up in my rant on EGR's a wasn't paying attention to the results, or Bag-O-chip's comments.

 

Now in after thought his problem is a rich condition, (my-Duh) but with high o2 levels is probably un-metered air entering the after the mass air sensor,

it could be a small hole or crack in his (swapped in ) intercooler or a clamp or hose on his intake pipes allowing the un-metered air to enter the fuel/air mix.

 

So Bag-o-chips gets a sincere apology,

and my excuse is I can be a real co-ck-eyed baggage.

I'm sorry Bag-o-chips was way closer to the solution than I was.

and I'll edit my posts to reflect that.

[Bag-O-Chips]

No Problems Bro we all have a misunderstanding ever once in a while. No Offense taken at all. We are such a small community that we can take things personally. All the information and misinformation is interpreted in different ways. In the end we all need to help each other out. Not every one here is a genius... I'm sure as hell not

 

-Chips