thatoneguy5x

so I took my car to get smogged today, I took it to one of those pass or don't pay places because I knew it wouldn't pass. the guy running the shop said he has never seen a car fail by so much. supposedly the HC count isn't supposed to pass 120, my car idled at about 110-125 and spiked at over 650 . the CO was a bit better but either way it failed. now I only have a couple days to fix it before my tags expire. my car usually runs fine, very reliable but lately it just smells like its pouring fuel out of the tailpipe.

ever since i replaced the all the gaskets its been idling very low (400's)
in the past 2 years ive replaced the spark plugs (twice),wires, vaccume hoses, cap and rotor, CTS, fuel filter, O2 sensor, swapped out a couple IAC sensors, MAP sensor, rebuilt my EGR, fuel pressure was within spec and held for the time required, checked the FPR ( unhooked vaccume line for 10 mins, no fuel leaked out) all my injectors had correct resistance, ive ran seafoam twice in 2 years, cleaned the TB, cleaned intake manifolds, tried idle re-learn multiple times, and im sure there are other things im missing but at this point im stumped and i have only a couple days to pass smog.

im out of obvious things to check. anyone have any suggestions as to what to check next? im on a tight budget at the moment so i rather not throw money at a bunch of new parts.

project89

iTrader: (1)

2.8 or 3.1

thatoneguy5x

sorry I totally forgot to post my ride!
92 Camaro 3.1 Auto with AC and cruise if it counts for anything. cruise is removed and AC is never used.

NCC-2569

iTrader: (1)

Go to a workshop, hook up a timing light, see if it pulses regularly.
No > possibly bad ignition control module on distributor

400 rpm for idle is way too low. That's minimum idle with the EST connector disconnected, which would be required to set your timing properly.
Is the brown one-wire connector on the passenger's side connected properly?

Fuel smell can be due to bad timing and fuel therefore not being ignited.
How do the spark plugs look? Are they wet?

Can you have someone connect your car to a computer and look at the values?

Base91

iTrader: (1)

You checked the injector resistance but that doesn't necessarily mean they're all working correctly. If they're original it may be worth replacing them (Southbay deal?) to sure you're starting from a good foundation.

thatoneguy5x

ive set the timing from 10*-12* multiple times to see if it helps out but it doesn't seem to do much. I heard you can check if the chain is stretched by opening the throttle a bit and seeing if the timing mark jumps a bit but mine just goes straight back where its supposed to be. the EST is connected properly I believe. when I plug it in my timming jumps up with the comp.
my car always starts on the first crank. spark plugs are only about 2 months old, I had bosh platinums in it but I swiched them out for delcos. it did a bit bertter.
Im new to the area and don't have anyone that can hook up my car to a comp. ive had bad luck with mechanics in the past and try to avoid them at all costs.

im gonna see if I can pull some used injectors from the scrap yard. I know its not ideal but $30 compared to $300 for new injectors.

ive also replaced thermostat, alternator and battery. just adding that to the list. I don't have any oil leaks, no oil in my coolant.

Mark RWC

WHAT CAUSES HIGH HYDROCARBON (HC)?

Below are common failures which are likely to produce high Hydrocarbon HC. Hydrocarbons are basically raw fuel, otherwise known as Gasoline. High Hydrocarbon (HC) emissions are almost always a sign of poor fuel ignition. However, it's not always that the engine's ignition system is responsible for high Hydrocarbon emissions. Read on. 1. Improper Ignition Timing - Engine ignition timing is measured in degrees before or after Top Dead Center (TDC). Example of an ignition timing failure would be in the case where an engine's ignition timing is required to be set at 10 degrees Before Top Dead Center (BTDC) and instead is set to 15 degrees BTDC. This fault will not only cause a smog check "functional failure", but will increase Hyrdocarbon (HC) emissions as well. California allows 3 degrees +/- off of the manufacturer's required setting. Note: Late model vehicle's may not have a distributor, and therefore no timing adjustment will be needed. On these engines timing is electronically controlled by the ECU (Engine Control Unit).
2. Defective Ignition Components Your vehicle's ignition system consists of the ignition coil/s, distributor*, distributor cap*, distributor rotor*, ignition wires, and spark plugs. If any of these components are defective the engine will produce high hydrocarbons. A common reason ignition components perform poorly is due to carbon build-up. High ignition voltage traveling through the air pockets within these components form carbon. Carbon acts as an insulator between paths of electricity, decreasing the energy required at the spark plug to ignite the air/fuel in the combustion chambers properly. *Distributor-less engines do not have these components.
3. Lean Fuel Mixture - Any condition which will cause unmetered air to enter the intake manifold, and ultimately the combustion chambers, will cause high hydrocarbons (HC). This condition is called a lean miss-fire. Such faults as vacuum leaks and gasket leaks will cause lean fuel/air mixtures. Broken, disconnected or misrouted vacuum hoses will do the same. It is also important to note that many engine components rely on engine vacuum for proper operation. If any of these components are defective, externally or internally, they may cause large vacuum leaks as well. A good example of such a component is your vehicle's power brake booster.

Select Type of Smog CheckRegular Smog CheckSTAR Station Smog CheckSmog Check Repair Miles: 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 30 Which Type Should I Choose?

Related Links:

• Failed High HC Emissions
• Failed High CO Emissions
• Failed High NO Emissions

4. Defective Catalytic Converter - A defective catalytic converter (CAT) may be responsible for high HC, CO, and NOx emissions. The Catalytic Converter, commonly referred to as the CAT is a component designed to continue the combustion process within itself and emit a more thoroughly burned and less harmful emissions containing exhaust. The most accurate way to find out if your vehicle's CAT is working efficiently is by using an exhaust gas analyzer. Unfortunately this tool is fairly expensive. Testing the CAT should be conducted at a smog check repair station.
Some obvious symptoms of a bad CAT could be any of the following:
a. Major loss of power over 15-25 mph. This may be an indication that the catalytic converter is plugged up and restricting exhaust flow.
b. Strong sulfer or rotten egg smell emitting from the exhaust on an otherwise good running vehicle. This may be an indication that the Catalytic Converter isn't burning fuel completely, instead storing it, then releasing it as hydrogen sulfide.
c. Loud rattle being heard from inside the CAT. This may indicate a broken Catalytic Converter substrate. You may want to insure this sound is not due to loose exhaust components, i.e. broken muffler flanges, loose exhaust pipes, loose or cracked exhaust manifold.
5. Defective Air Injection Components - Faulty smog pump and related emissions system components will cause high HC. The air injection system is designed to introduce additional oxygen, after the metering system, to the engine exhaust as it exits the exhaust manifold, or directly before it enters the Catalytic Converter; thus burning whatever remaining fuel (HC) in the exhaust completely.

6. Low Cylinder Compression - This fault is one of the less common high HC causing problems we encounter. Reasons an engine may have low or no compression in one or more of its cylinders may include things such as burned intake or exhaust valve/s, defective valve guides and/or seals, defective piston rings, and burned head gasket/s. A wet/dry cylinder compression test will diagnose this fault. More then often if such a problem exists it will be very apparent. You should notice rough idle.

Mark RWC

My 88 firebird V6 failed with high HC when I first got it. The HC levels were 109 and 88 for the test and 83 and 61 were the maximum allowed. The quick fix to get it to pass was to have a new catalytic converter installed. If you are in the bay area mine was about $220 installed but many shops are much higher. With the new CAT the HC were 24 and 20.

Southbays price is very reasonable for fuel injecters about $136 plus shipping for a set of six. Mention you are a TGO member and you get a discount.New rebuilt bosch injecters will probably make the car run better but they may not be your problem with the high HC.

Before throwing parts and money at the problem it would be a good idea to check the engine vacuum reading since you say the idle got really low after the gaxkets were changed. Do a compression check on the cylinders to see what the condition of the engine is.
When you retest make sure the oil is clean and most of all the engine is hot by running it atleast 20 minutes on the freeway and have it tested when it is still hot. Try not to let the car sit at the test station waiting to be tested.

Good luck it is a real pain when the car fails

thatoneguy5x

thanks for the link. im gonna recheck all the components. what do you guys think is a better timing for better fuel burn 10* or 12*? also I pulled some used injectors today they were all within 0.2ohm resistance from each other but I don't know what brand they are. I have a feeling they are multech.
i read in another thread about TPS voltage but i can seam to find it again. anyone know what its suppose to be putting out at idle?

Mark RWC

TPS setting at idle .5 and 5 volts wide open throttle.This is per my 88 service manual not sure about you r year.

Base91

iTrader: (1)

You can't change the timing it's part of the smog check. Start with the Southbay injectors it's a good deal and unless you know the injectors are good everything else is a waste of time and money.

thatoneguy5x

what do you mean its part of the smog? ive never had a smog where they check your timing.

Mark RWC

Check your print out of the test when they give it to you as they do check timing with a timing light. 10BTDC was listed the last two tests I passed. There is label either under the hood over by the raditor they look at to see what the factory timing is. If it is missing the Star station has a number to call to find out what it should be. My friends 89 V6 was missing the label for timing and the tech had to make a call to get the spec.

I think it can be off by only two degrees. My truck 350 V8 is set to 0 but the Star test sheet showed 1BTDC and it passed a few months ago.

thatoneguy5x

the shop I took it to was kinda simple. he pretty much opened the hood shoved the probe in the tailpipe made sure I had a cat on the car and revved the engine. it wasn't on any type of roller system. car was in park the whole time. I don't think they were too concerned with things like timing. after all they don't get paid unless I pass. they didn't give me a print out either. I was overseeing the monitor and he was telling me where its supposed to be and all.

thatoneguy5x

would running a higher octane help burn everything more completely?

project89

iTrader: (1)

no the higher the octane the slower it burns

more then likjley the car is running super rich check the map sensor line and map sensor , check the o2 sensor

Mark RWC

If you are required to go to a star station the actual test has several parts.
15 and 25 MPH on the rollers with probe in exhaust. Check all hoses PCV ERG and cat to make sure they are there and connected. IgnitionTiming. EVAP test to make sure no fuel vapors are leaking.
Since your guy does not charge unless you pass he stopped as soon as you failed.The pass or retest for free shops run the complete test and then give you a printout showing what passes or fails.
It is a good idea to put in a new PCV valve since they are less than 5 bucks for a generic one. If the battery is disconnected for some reason it is a good idea to drive the car for several days so the computer has all the correct feedback from the sensors.Do an idle relearn at a minimum.
Do you have a vacuum gauge to test with. It should read about 15 and stay pretty steady It can be helpful to know this reading.You set your timing with brown wire diconnected and said it was steady so that should be ok. You also indicated your fuel pressure was good.If you know someone with tunerpro you can read the fuel trims with BLM of 128 being normal.
What gaskets did you replace when the idle dropped so low?

thatoneguy5x

the shop was star certified and didn't have a roller in the shop. I watched them do the car before me a mid 2000's Toyota. he passed, got his print out and everything. went through the same procedures as I did. just revving the engine. I was surprised by the lack of equipment (thought it might work in my favor lol) but either way. I have replaced the PCV valve and grommet. its hard to remember the complete list since there are so many but that has been replaced.

when I did the gaskets I used a felpro intake manifold kit from autozone. ive replaced 90% of my vacuum hoses with the exception of brake booster and cruise control but I got rid of all the cruise stuff. idle holds steady doesn't jump at all while idling. used a couple cans of carb cleaner and other methods to check for vacuum leaks. none found did another fuel pressure test and it was still all good, held pressure for 35 mins then slowly started dropping over the next 30 mins

I noticed though that the throttle stopper screw didn't have the cap over it to stop people from messing with it. maybe the PO messed with it?? just out of curiosity what is everyones car idling at when you fist start up in Park and then in Drive? then again at temp?

MAP sensor and hard line going to it have both been replaced. it was a used MAP though, it didn't make any difference.

Mark RWC

I started my 88 V6 and the idle starts around 1200 rpms and drops to around 750 or 700 in drive once it is warmed up. It is around 800 or a little higher in park.

The factory label says the idle is preset and not adjustable.

Did you clean the idle air control and the passage to the throttle body? Has the TPS or throttle position sensor been replaced and set to .5 VDC if it was replaced?

I assume you have checked for error codes and are seeing only the normal 3 flashes of 12. My car did not show any error codes when i got it and it did not pass.

There is a thread on here about how to adjust the idle once the cap is pryed off.


Are your new plugs wet with fuel or black with carbon from unburned fuel?


If you do not get the problem solved in time send in your registation payment so you do not get a penalty.You probably can drive till the end of the month before worrying about getting stopped for an expired registration.

thatoneguy5x

on the 3.1 I don't believe there is any way to adjust the TPS without messing with the idle screw. the manual says TPS voltage should be between 0.35 and 0.67. sounds like a large margin to me. (might try playing with it a bit) im about to get in the garage and pull the plugs again make sure they are in good condition and properly gaped again.
throttle body had been cleaned AIC has been cleaned. pretty much everything was cleaned/degreased when I did the gaskets.
no codes are being thrown out.
and I already took care of registration payments, all im waiting for is my smog certificate so I can get stickers.

thank you for checking your idle Mark, and everyone else for the replies. that's why I love this site

NCC-2569

iTrader: (1)

400 RPM in idle is what your engine should have with the EST disconnected, before you set your timing.
If the cap is missing, someone tampered with the screw.
Probably had a vacuum leak and tried to "fix" it this way.
Try disconnecting your EST and see what idle speed is then.

thatoneguy5x

so in order to adjust the screw correctly I need to have the EST disconnected right? otherwise the computer would just take over.
I know that when I got the car ALL the vacuum hoses were a mess. everything was hooked up wrong and there were hoses not hooked up to anything. since then ive sorted all the hoses out. so maybe they did try to compensate the vacuum leaks with throttle screw.

Mark RWC

This is the idle adjustment found here.
https://www.thirdgen.org/forums/v6...rocedures.html (idle adjustment procedures)

thatoneguy5x

hmm there's some good info but I don't have a ALDL cable. im gonna see how well the 1.5 turn leaves it.

NCC-2569

iTrader: (1)

Ok, so it's not 400 RPM... that would have to be the V8s then.

thatoneguy5x

is the 500 RPM the same for 2.8 and 3.1?

Mark RWC

maybe some with a 91 service manual can help. the link I sent earlier had 550 listed as an edit at the bottom SEE BELOW

Edit - 9/6/2004:
Changed idle RPM numbers for 2.8L engines to 500 and 600 RPM from 550 and 650 RPM (these are the numbers found in the GM service manuals).
Added step instructing removal of jumper between ALDL A & B terminals before starting engine (due to possible ECM damage - see this link for details as to how this can damage the ECM: https://www.thirdgen.org/forums/po...410-post6.html ). Added step instructing the connecting of A & B terminals after engine is running to place the ECM in Field Service Diag. mode.

graysmoke

I had a rich smell going on for awhile. Today i had exhaust work done and when the cat was removed I could see through it. It just rotted out over time. It was the factory cat with 101k miles. Went with new HF cat.

thatoneguy5x

that last par is worded a bit odd but im pretty sure he's saying the original post was 550 and he edited it to 500. so 500 would be the correct final idle but that's listed under the 2.8 no idle is mentioned for the 3.1, it only mentions IAC counts.

@graysmoke: I know sometimes with a bad cat you get a sulfer smell or the car doesn't run well (no power) but I haven't experienced any of that. I tried to remover the cat to check it out but its welded from the front side. I was able to pull off the back end and it didn't look bad at all. but looks can be deceiving I guess.

Mark RWC

Out of coureousity is this the first California smog test you have had with the car?
The service manual for my 88 shows the cat was originally bolted, so you may have a replacement.
I have a temperature gun that I used to check the cats on my car and truck. The temperature on the weld of the cat nearest the engine should be lower than temperature of the weld at the back of the cat.
If you google "testing the catalytic converter with temperature gun" you can find several informational videos. I looked at the one by Walker and a second by ERIC the car guy when I was trying to diagnosis the problem. Current replacement cats for California are reqiured to have leters that readable from atleast 5 feet away. That law to raise the price of cats here in California and is several years old.The cat you are looking at my older even if it is a replacement.Raw fuel shortens the live of your cat.Severe discoloration is supposed to an indicator of an overworked or bad cat.

Sorry if i created confusion misreading the idle specs. My service manual covers only 1988 so 1991 maybe different.

thatoneguy5x

that's very interesting info. and no worries about the confusion I had caught it when I first read that thread. i'll take another look at my cat tomorrow to see if I can find any kind of markings and see if I can locate a temp gun or something. I have a good feeling about all the info you guys have been giving me. I roughly adjusted the idle and can already tell its not AS rich. all moving in the right direction

and yes its the first smog I will perform with this particular car. when I got acquired the car it had just "passed" smog so I have been good the last 2 years.

Mark RWC

The link below will let you see the California state history of smog checks on your car.
www.bar.ca.gov/pubwebquery/vehicle/pubtstqry.aspx

I found out my car had failed and then passed the same day on the smog test about 1 1/2 tears before I bought it.It may give you an idea on how poorly the car was maintained before you got the car.This site only shows date of the test and pas or fail. No detailed records.

thatoneguy5x

that's an awesome site! its passed every time, no fails at all except for in 2011 got a "T" meaning something emission wise had been tampered with. I wish It also recorded the data. that would be way more helpful.

Mark RWC

If you decide to get a cable in order to able to see what is going on with your sensors and fuel trims. This where mine came from and tuner pro was on the CD that came with it. They are in California so it comes quickly. Moates also has cables. You have to find the information specific to your ecm and prom to use it.Tuner pro is a great tool as you probably have read here on the site.

aldlcables.com

thatoneguy5x

thanks i'll keep that in mind. as much as I would like one, im on a college students budget and work has been pretty slow lately.

NCC-2569

iTrader: (1)

Yeah, I recently hooked up my car to my laptop using one of the cables aldlcables.com sell, because a buddy asked me to try the cable he bought from them.
Worked great with TunerPro!

thatoneguy5x

so an update. I haven't been able to work on my car much until today. the cat didn't have any markings on it but it doesn't look bad (beat up/old) I know that means nothing but gives me a general idea of the condition. couldn't see any welds on it but I couldn't get it off.
I set the timing back to the factory 10*
I did the idle adjustment step by step in accordance to the thread linked above. I didn't have any way to see what the IAC is doing but the TPS is sending out 0.63v which is in spec with the manual.
checked for vacuum leaks anywhere and everywhere (none found).
spark plus were re-gaped.
cleaned the TB even though it was cleaned in the past couple months.
reset the ECM
im happy to say my Camaro is running smoother (less engine vibration), idle is much better. idling at around 750-750 when at temp in park and mid to low 500's in drive, these are guestimates of course, I don't know how accurate my tach is. but best of all its not running "AS" rich anymore! if rich at all.
I should be taking it in for a smog in the next couple days, im gonna do an oil change and check a couple other things before I take it in.

I really appreciate all the help and advice you guys gave me, it helps out a lot. i'll post up if I passed or failed when I take it in!

NCC-2569

iTrader: (1)

Please do!
Your park-idle sounds ok and the 500 in drive should in fact be a bit higher than is being displayed.

TPS at .63v is a bit high IMO, but if it doesn't suddenly jump or drop in its values when you slowly open the throttle, it's still realistic and the ECM should be fine.

thatoneguy5x

the 0.63v at the TPS is where it lands when I do the turn and a half like it said in the idle adjustment. manual says 0.35-0.67 is where the TPS should be, Im a bit on the high end of that.

so to test it I hook up the meter and slowly open the throttle and if it goes up gradually instead of jumping all crazy it should be good right?

NCC-2569

iTrader: (1)

Yup.

thatoneguy5x

ok so i took it to get tested today. and well It failed again.
HC=290-330 supposed to be under 120
CO=12.4 supposed to be under 16
CO2=1. supposed to be under 2
i didn't get a sheet because they didn't do a full test since it failed from the second they stuck the probe in.

HC are usually caused by too much fuel, im kinda stumped. i picked up a new O2 just in case.
has anyone ran "guaranteed to pass" I've heard that its pretty much the same as seafoam.
also when i first bought the car i swiched my intake from the stock single snorkel to the earlier dual snorkel intake, would this have any effect on this? ive heard on later model cars running a different intake usually a higher flowing one could actually cause the car to run worse without a proper tune.

Reid Fleming

iTrader: (2)

Have you changed out your ignition coil? If that's bad, it won't be igniting the fuel and thus giving you raw gas. How old is the catalytic converter?

thatoneguy5x

haven't changed the coil and I have no clue how old the cat is. I don't think the cat is stock though. the PO redid the exhaust I believe. I don't know when it was done though.

thatoneguy5x

so I noticed that my idle is back down under 500 in drive when warm? I just got a new ignition coil and installed it. haven't driven it around yet but we'll see if it makes any difference. im gonna do a compression test next.

thatoneguy5x

so I did a compression test, I couldn't get it while the engine was hot mostly because I burned the hell out of my hand trying to get #1 sparkplug. so I did it when the engine was warm but not operating temp. I don't know if I did it wrong or something but the compression built extremely slow on all cylinders. i read that slow build up means worn piston rings but i thought it was odd that it was on all cylinders. the car sat for 2 weeks and only moved from the driveway into the garage i don't know if that has anything to do with it.
opinions?

also i did the paperclip trick and pulled code 32 and 35.

32:Fault in barometric pressure sensor circuit OR Fault in exhaust gas recirculation valve diagnostic switch OR Fault in electronic vacuum regulator valve

35:Idle speed can not be set to desired RPM.

that would explain my 500 - <500 RPM. anyone shed some light??

RamIt

What was your procedure for doing your compression test?
Just wondering if you had the throttle wide open for the test.

Mark RWC

What were the compression readings? Mine were somewhere around 150 to 155 if I remember correctly with all cylinders within a few pounds of each other. Did the compression gauge have a threaded screw in adapter with a hose that you can use to screw it in to the cylinder. I had a real cheap one 30 years ago that you had to hold in place while the engine is cranked. This older type would not be the type to use on our V6 engines and would lead to burned fingers. You are usually looking for a big difference between the cylinders in the readings you get or very low readings on all cylinders.
Now that you found some error codes you might want to remove the ecm fuse or disconnect the battery and see if the codes are coming back. I do not have a 3.1 like you do but I did a search here for error codes for 3.1 engines and I did not see code 35 . The list was from austinthirdgen.org

32 code was "The ECM opens each EGR control valve during deceleration and monitors the change in manifold vacuum. The code sets when the change in manifold vacuum is outside the normal range"

I do not know if there error list is correct but if it is I would do a vacuum test with a gauge. You want to see steady reading of over 15 on an older V6. A cheap one the reads fuel pressure for older cars with low fuel pressure and vacuum as well will cost a little over $16 since you are a student on a budget. You might be able to get one from autozone on ther free loaner tool program but would probably require a deposit. Is the error list you have from a factory service manual?

I saw your car failed the test again around the 4th of July. The new coil you installed was a good idea because a weak coil leads to unburned fuel and higher emissions.

thatoneguy5x

the compression gauge was the more modern screw in type, i got the error codes off thirdgen.org.

my procedure for doing the compression test was warm the engine, pull the plugs, unplug the ignition coil, unplug injector harness, hook up the compression gauge, hold gas pedal to the floor and crank the engine.
it was taking a long time to build pressure in all cylinders, only went up around 10-15 psi in each cycle. felt like i was it was taking forever so i didn't complete the test for any of the cylinders.

car doesn't have any coolant or oil loss.

thatoneguy5x

I know this is an old thread but to anyone who was following. I FINALLY got my car to pass. new cat, some tweaking of the IAC/throttle positioning screw, and changed out the valve stem seals. im sure it was more the new cat than anything else. thanks for all the replies guys.

Mark RWC

Congratulations on passing the smog test here in the state of California. California residents are getting ready to pay a carbon tax on gas and other things starting January 2015. The gas tax is already between71 to 74 cents per gallon but that is not enough for the wackos running the state.



Your hard work has paid off even though it was probably very annoying while you were working your way through the problems..How long did it take you to install the new cat ? I was surprised at how high the quotes you got were to replace the cat. I might have done mine myself if it costs over $300 to replace.



It might be helpful to others here in California if you can provide the results of the test that you passed. I am wondering how low the hydro carbons are on the test you passed