Costco may NOW be a Top Tier brand, but that doesn’t mean it’s always been a Top Tier brand.
For example, I’ve fueled my vehicles up at Kwik Trip for years because they’ve been a Top Tier brand.
But if you look at the list, you’ll also see the Super America and Holiday brands listed.
Those brands became Top Tier just a few months ago.
Tester
On the way to the SMOG, I did deliberately hit hard on the gas but at 50-60mph, it was not that responsive at higher speeds - what might be the cause?
The car normally runs fine and it has been a fun car to drive and very versatile.
OP writes …
This car has FI but does not have an EGR
Not saying you are wrong OP, you should know since it is your car; but the documentation I’m looking at for the 1987 Acura Integra 1.6L shows it having an EGR system used to reduce oxides of nitrogen.
Edit: I check on Rock Auto, and there it seems to say there is no EGR on a 1987 Acura Integra. hmm… well, my documentation source may be incorrect then.
Edit again: Seems there’s a version of this model with a larger engine called the “Legend” and Rock Auto says that one has an EGR.
I used to de-carbon engines using a squirt gun. It kept you from accidently spilling too much water in too quickly.
here’s an idea . . .
Take out all of the spark plugs
Now use a borescope to look at the pistons . . . see lots of carbon buildup?
It’s just an idea
If there's a lot of carbon on the intake valves, this carbon can act like a sponge and absorb some of gasoline that's supposed enter the cylinders. So at low RPM's when the injectors are providing less gasoline, and the carbon is absorbing some of the gasoline, it leans out the mixture to the cylinders. This then causes the combustion temperatures to increase, which then causes increased NOx emissions.
Tester:
So you’re saying a lean mixture in general can cause high NOx (where carbon on the intake valves can be one reason for it).
If that’s true, then anything that can cause a lean mixture should equally be suspect. E.G., vacuum leaks, faulty O2 sensors, maf sensor, etc.
@db4690
I can look with a borescope - but based on the youtube video posted by @Tester - the kid is claiming ton of improvement with Sea foam - but for my eyes, I do see a different - but there is a judgement call - I only see a marginal improvement but I am inexperienced - one should have seen plenty of these to make the call based.
I have CRC branded Throttle body/air intake cleaner - am I correct that this does not clean the pistons? If my Toptier gas cleaned the pistons, perhaps CRC I have is enough - O2 sensor needs testing.
:trollface:
I didn’t think carbon buildup was an issue with modern engines. I usually run top-tier gas, but always regular 87 octane stuff. A couple weeks ago, my car (Versa with the 1.8 L engine and 6-speed stick) was running like crap…It would stumble a bit off idle and it was very difficult to pull away smoothly from a stop. Also difficult to shift from first to second gear smoothly. After second, the gear ratios are closer together, which helped for smooth shifts.
One day on my way home from work, I started giving it more throttle and running it a bit on up hill streets, finishing with 15 or so seconds of full throttle at about 3,000 RPM on the hill up to my house. I let it idle in my parking spot for about 30 seconds to let the heat drain out of the heads before shutting it down for the day. Darned if it doesn’t run a lot better now!
^^ The “Italian tune-up” lives!
;-]
I think carbon build up IS alive and well . . . particularly for direct inject engines
There are products out there similar to seafoam, but better formulated for today’s cars/gas. Here’s Scotty Kilmer testing Gumout’s engine cleaner.
Why’d you have to bring up Scotty Kilmer
His personality . . . makes me wonder if he guzzles an entire case of Mountain Dew . . . or maybe even Jolt Cola . . . before making his videos
He’s so “peppy” . . . maybe he should replace Manny, Moe and Jack as the face of Pep Boys :naughty:
Their web site says, although this is an additive to gas, “Add entire bottle to nearly empty gasoline tank at time of oil change” - are they recommending change of oil right after using this?
https://gumout.com/multi-system-tune-up/
@sciconf Looks to me like they’re just using the oil change as a way to mark how often they want you to use their product.
@“Mike Wretzel” - thanks for the tip.
I have occasionally seen disaster of using these types of additives - read for Sea foam too - below is another:
http://www.bimmerforums.com/forum/showthread.php?1870982-USE-WITH-CAUTION!!!-Gumout-Regane-Complete-Fuel-System-Cleaner
Should I not use Gumout or Sea foam? There is also a review with CEL on Amazon.
Kilmer must be on the Gumout payroll…
I don’t see how you can spend months experimenting with gasoline additives if your registration is due for renewal. How much time do you have before it expires?
You could suck distilled water in through the intake via a vacuum line or similar to steam clean the pistons. I also like to do this right before an oil change as some water may get into the oil.
The Italian tune-up is still valid. I have used it on some older cars that have been neglected and use some oil. I make sure the oil is fresh and up to a proper level, and then take the car out and drive it like it is stolen. I leave it in third gear and floor it getting onto the highway, shifting to 4th around 500 RPM from redline. I notice smoother running and reduced oil consumption after doing this. It seems stuck rings popped loose and am sure any deposits from oil burning are vaporized. You might try this first as it is easy.
Is this true for car such as mine:
"if the car was “ready” for a smog check (sometimes, for example, if you had some recent car work done that required disconnecting the battery, the smog check will fail till you’ve driven around a few hundred miles "