Gas mpg going down?

[tqk]

04 ep3 wit 82k. I used to get 30 mpg driving around town about 6 months ago. Now down to 25 mpg. Always change oil on time recently changed plugs. Only thing wrong is the occasional CEL because of a rusted/holey CAT. Is the CAT causing me to lost mpg. Engine is pretty stock with cold air intake n cat back exhaust. Any got some insight?

[USAF EP3]

Yes, if the catalytic converter is clogged you will greatly suffer a loss in MPG's. If you don't wanna fork over hundreds for a converter, buy a Megan racing testpipe they're about $115 (direct fit/bolt-on to stock) and a secondary O2 sensor defouler for about $30 from ClubRSX.

If your state has emissions...well I don't know what to tell you. You won't pass a sniffer test that's about all I can say. You can try and find a use converter but you run into possibly getting another clogged one, so it's a risk you're taking buying used.

After you figure out what you want to do with the converter, do a seafoam treatment through your brake booster hose and watch your MPG's come back. Good luck.

[tqk]

seafoam? n what do i do just get some and spray and clean and reinstall?

[ep3colin]

certain states that have emissions will do an obd2 CEL test, as long as it hasnt had any codes recently then you pass, i passed with a raceheader lol

[USAF EP3]

Seafoam is a product you can buy at any auto parts store (Autozone, Advance, O'Reilly, etc.) or at Wal-Mart. It's usually on sale at auto parts stores though

To use it you pour half of it into a cup or container. Start your car and disconnect the hose that goes to the brake booster from the intake manifold, cap it with your thumb. SLOWLY raise your thumb and let the vacuum created from the manifold SIP the Seafoam from the container. It'll take at least 5 minutes to do this.

Once it sips all the fluid, shut the car off and let it sit for 5 minutes. Start it back up again. You will see a metric SHIT TON of smoke, the color will vary, lol. Rev the car, drive it, do whatever it takes to clear out the smoke and voila, you have just performed a seafoam treatment.

Take the rest of the fluid and pour it into your gas tank before you fill up the tank.

[tqk]

What end am I holding? The end that goes towards the brake resevoir or the part that goes to the manifold? Disregard this. I just answered my own ?

[Red_liner740]

Seafoam is great, but in this instance, hows it going to help? the fact that he is already getting CELs for the catalytic means that no treatment will help him.

if you dont want to buy oem, there are high performance cats that can be welded in place of the oem for cheaper...

[USAF EP3]

Seafoam is great, but in this instance, hows it going to help? the fact that he is already getting CELs for the catalytic means that no treatment will help him.

if you dont want to buy oem, there are high performance cats that can be welded in place of the oem for cheaper...

If you read my first post you will see that I offered a solution for his catalytic converter problem, THEN gave him additional advice to supplement the tune up he performed to maximize his MPG's.

[doubledouble]

I want to try seafoam. Anyone have pics as to where it goes?

TTITYWWOP!

[doubledouble]

I want to try seafoam. Anyone have pics as to where it goes?

TTITYWWOP!

[gtecd20]

just found this one youtube its a 04 ep3 seafoam treatment hope it helps
http://www.youtube.com/watch?v=A6RdJeMwNxw

[gtecd20]

is it safe to seafoam a ep3 with a JRSC street?

[willy_akino]

is it safe to seafoam a ep3 with a JRSC street?

i wanna know too! i have jrsc race kit.