How to lower hydrocarbons

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Bbonez

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Santa Barbara North County
I just got a truck from my in-laws it is a 1995 Chevy 2500 with a 5.7L V8 with 230K miles. I failed smog due to high hydrocarbons at idle, I was at 409 PPM and need to bring it down to 150 PPM. I replaced the plugs and wires they looked to be original to the motor and some plugs were very loose (not even hand tight)the gap on the old plugs were from .04 to .06 and should be .035. I put E85 today and plan to do a seafoam treatment and slightly retard the timing tomorrow. Does anyone know if the stuff I am doing will help? Does anyone have any other suggestions? The oil has less then 100 miles on it and it is Chevron 10w30, I just changed it before the smog test.

Thank You
 
Why E85?

In a 1995 truck not set up to be flex fuel, if anything it could make matters worse (higher octane not willing to combust at the right point), and/or destroy plastic and rubber parts in your engine.
 
While the valve stem seals are off, place one drop of Marvel Mystery Oil on each valve stem and let it soak into the guide, to dissolve carbon. A sticky valve that doesn't fully rest on it's seat will kill your emissions efforts.

I also hate to say this because I think I'm going to get flamed for it, but a drop of STP on each valve stem when you put the new seals on might help, but no guarantees.

Some folks will say a tablespoon of seafoam in each cylinder through the plug hole will help dissolve carbon on the pistons rings and "free them up" a little more. YMMV.

Did you do a compression check yet? What are the numbers? If you have really low compression numbers, any number of "band-aid" fixes won't help.
 
quick google suggestions say:
check for/fix any Vacuum leaks
Check/Replace
PCV valve
Catalytic Converter.
 
Last edited:
Originally Posted By: JHZR2
Why E85?

In a 1995 truck not set up to be flex fuel, if anything it could make matters worse (higher octane not willing to combust at the right point), and/or destroy plastic and rubber parts in your engine.


Some folks in Houston swear 1-2 gallons of E-85 in the tank will "oxygenate" the fuel enough to help it pass. I can't say whether it does or doesn't - - every engine is different.
 
Plugs and wires are likely all thats needed ..i would suggest burning the e85 out before testing again can't see this helping ??
fill it up with regular gas take it for a good run on the highway then try your smog test again.
 
Originally Posted By: Linctex
Originally Posted By: JHZR2
Why E85?

In a 1995 truck not set up to be flex fuel, if anything it could make matters worse (higher octane not willing to combust at the right point), and/or destroy plastic and rubber parts in your engine.


Some folks in Houston swear 1-2 gallons of E-85 in the tank will "oxygenate" the fuel enough to help it pass. I can't say whether it does or doesn't - - every engine is different.


I'd understand if NOx is an issue, since adding alcohol cools the burn. I'd understand if it was CO. And I sort of get it if it's a few gallons in 20-ish. A full tank may have other ramifications.
 
Alcohol will help pass as it has burns cleaner and has less carbon. But not too much, i'd aim for about 20% but not much more in a non flex fuel vehicle. AS JHZR2 stated, you don't want to ruin plastic or any other fuel seal not designed for e-85.

You may pass with new plugs and wires.

Don't put seafoam in there, it contains pale oil, you want less carbon in your fuel mix for clean burning, not more.

Seafoam is naptha, IPA( Alcohol), and pale oil.

Just run a bit of E-15 fuel with with everything you have done, and see how it does. Make sure the engine thermostat keeps the motor up to proper temp. Drive a good 15 miles or so before the test to make sure its good and warm.

.
 
OK, thank you all for the replies. The gas tank was empty and I only put 5 gallons of E85 in because I hear it burns cleaner, but I can add some regular unleaded if you all think it would be better. Has anyone ever tried "CRC Guaranteed To Pass Emissions Test Formula" its only $9 and had a double your money back guarantee.
 
Originally Posted By: Bbonez
OK, thank you all for the replies. The gas tank was empty and I only put 5 gallons of E85 in because I hear it burns cleaner, but I can add some regular unleaded if you all think it would be better. Has anyone ever tried "CRC Guaranteed To Pass Emissions Test Formula" its only $9 and had a double your money back guarantee.


Here is msds ingredients for crc guaranteed to pass.

You are paying $8 for a few ounces of diesel fuel and naptha and some other things.

I think the e-15 will do what you want with out it being $70 a gallon.

http://www.crcindustries.com/faxdocs/msds/5063.pdf


8. Exposure controls/personal protection
Occupational exposure limits
US. OSHA Table Z-1 Limits for Air Contaminants (29 CFR 1910.1000)
Value
Components
Type
PEL
50 mg/m3
Naphthalene (CAS 91-20-3)
10 ppm
PEL
400 mg/m3

Solvent naphtha
(petroleum), heavy arom.
(CAS 64742-94-5)
100 ppm
US. ACGIH Threshold Limit Values
Value
Components
Form
Type
TWA
100 mg/m3

Inhalable fraction and
vapor.
Diesel Fuel No. 2 (CAS
68476-34-6)
TWA
5 mg/m3
Inhalable fraction.
Distillates (petroleum),
sweetened middle (CAS
64741-86-2)
TWA
10 ppm

Naphthalene (CAS 91-20-3)
TWA
200 mg/m3
Non-aerosol.
Solvent naphtha
(petroleum), heavy arom.
(CAS 64742-94-5)
US. NIOSH: Pocket Guide to Chemical Hazards
Value

Components
Type
STEL
75 mg/m3
Naphthalene (CAS 91-20-3)
15 ppm
TWA
50 mg/m3
10 ppm
3 / 9
Material name: Guaranteed To Pass® Emissions Syste
 
Last edited:
Make sure the correct pcv(oem) is in there. Replace vacuum lines and verify you have no air leaks at your throttle body.Leave timing at specs.
 
4 out of 5 stars:
https://www.amazon.com/dp/B01LFXTAE2?psc=1
OXICAT - Oxygen Sensor & Catalytic Converter Cleaner by AUTOPROFI

I saw a YouTube video a while back where some guy soaked a catalytic convertor in some kind of caustic solution.... said it worked perfect afterward. No idea what it was - - maybe oven cleaner? That stuff is nasty and will remove all kinds of baked on crud. I'd like to see a more credible test, though.
 
Originally Posted By: spasm3
Make sure the engine thermostat keeps the motor up to proper temp. Drive a good 15 miles or so before the test to make sure its good and warm.


There's a lot to this..... I've heard many Houston folks say it is VITAL to get the engine good and hot and do not let it cool off at all before testing! They say make sure you can "arrange" with the tester to drive it hard and immediately sniff it the moment you arrive after the drive.
 
Originally Posted By: Linctex
4 out of 5 stars:
https://www.amazon.com/dp/B01LFXTAE2?psc=1
OXICAT - Oxygen Sensor & Catalytic Converter Cleaner by AUTOPROFI

I saw a YouTube video a while back where some guy soaked a catalytic convertor in some kind of caustic solution.... said it worked perfect afterward. No idea what it was - - maybe oven cleaner? That stuff is nasty and will remove all kinds of baked on crud. I'd like to see a more credible test, though.


Oxicat

http://www.efi.com.au/images/pdf/MSDS-Oxicat-OXI.BC_SDS_EN1.pdf

Alcohol and some benzyl alcohol and some gasoline.

A lot of money for a few ounces of gasoline with alcohols in it.

C No
Chemical name
30 - 35 %
Distillates (petroleum, gasoline), hydrotreated light
919-164-8
Xn - Harmful R52-53-65-66
64742-82-1
Asp.
Tox

. 1, Aquatic Chronic 3; H304 H412
30 - 35 %
2-ethyl-hexanol
203-234-3
Xn - Harmful, Xi - Irritant R20-36/37/38
104-76-7
Acute Tox
. 4, Eye Irrit. 2,
STOT SE
3, Skin Irrit. 2; H332 H319 H335 H315
30 - 35 %
Benzyl alcohol
202-859-9
Xn - Harmful R20/22
100-51-6
Acute Tox

. 4,
Acute Tox
. 4, Eye Irrit. 2; H302 H332 H319
Full text of R and H phrases: see Sectio
 
Originally Posted By: Linctex
Originally Posted By: spasm3
Make sure the engine thermostat keeps the motor up to proper temp. Drive a good 15 miles or so before the test to make sure its good and warm.


There's a lot to this..... I've heard many Houston folks say it is VITAL to get the engine good and hot and do not let it cool off at all before testing! They say make sure you can "arrange" with the tester to drive it hard and immediately sniff it the moment you arrive after the drive.


Good point. If there's someone in front of you at testing, hold a fast idle while waiting in line and don't shut off the engine.
 
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