mrcombs

Okay, so I've read all or most of the previous threads about poor fuel economy remedies and also just cleaned the EGR ports on my '99 TL per the DIY after I got a P0401 code and CEL. That DIY was very helpful and I did the job in about 3 hours, saving myself several hundred dollars and, at the same time, getting a nice feeling of satisfaction after doing it with my own hands. Thanks for the help everyone... But now, I'm worried I've screwed it up somehow!

The car was a little rough to start right after the cleaning, but after a second try it fired up and blew out a pretty good cloud. Reset clock fuse -- no more CEL. Sweet. Now seems to be idling better and the throttle response seems to be better as well, but my fuel economy is worse than before the cleaning -- like 11MPG worse! I've got new, properly inflated rubber all the way around, regular oil changes with conventional oil and most all of the other items the other threads suggested (including Seafoam in the tank) to combat poor fuel econ. The thing is that the drop in performance appears to be related to my EGR cleaning.

I did my level best to keep carbon debris from entering the engine. It's no problem when cleaning the IM side port, but a little trickier on its sister port. Some of it just has to be blown thru with TB cleaner. I did not remove and clean the EGR itself. I've triple checked all the hoses and other re-connections and they all seem to be fine, too. The one instruction I couldn't follow exactly from the DIY was the torquing specs when remounting the IM to the engine. No torque wrench, so I just tightened to about the same pressure I encountered in removing it. Forgive me if that is an idiot thing to say, but that's what happened.

Finally here's my question: Is there a "seasoning period" after cleaning the EGR ports where poor fuel econ results from burning off carbon debris? Have I clogged the EGR valve itself or a fuel filer of some kind with debris? What else could I be missing? Any advise you can offer is, as always, deeply appreciated. Thanks.

01tl4tl

not sure how you cleaned the manifold with the EGR valve attached?
need to remove it- (lube arm with wd-ck operation)
clean the ports under valve into manifold
AND
must run a wire rod/metal coat hanger thru the length of the manifold from mouth end to egr valve end--cleaning the actual passage from one end to the other,, not just the openings~

the little bit that gets into lower section: shop vac helps, but its not a disaster

our fuel filter is inside gas tank=- no issue there

Torque is critical on all these bolts, 16 ft pounds isnt much, and a vac leak kills mileage and performance

possible gasket leaks too,,,removed TB to manifold to clean iacv and TB air plate?
might need gasket there- suggested replacement with this job

And the biggie-it is possible to install the uppermost gasket -to cover- upside down
looks right, but blocks an important port on the cover side
Match the gasket to the cover side then install
If installed wrong it often has idle prob

buy or borrow a $20 torque wrench- go back and do the work right with the poking

01tl4tl

another can of seafoam in half a tank will get rid of any carbon issues

mrcombs

Naturally, I "disconnected" the EGR Valve from the IM/TB to remove the IM, but I just looked again and nowhere in either of the 2 DIYs does it mention physical removal or cleaning of the EGR Valve itself to accomplish the job. Just removal of the IM for a good thorough cleaning and cleaning of the 2 ports for the 1999 model. Are you saying that info is missing from the DIY? After digging and vacuuming the opening, I ran a wire-like brush down thru the lower manifold port several inches until i felt it "open up" then cleaned that entire length really well, but never did I see or hear TB cleaner blowing out the other end of a line somewhere. I just figured what I didn't vacuum out would melt away with the cleaner and get burned off.

The IM gasket is installed correctly. I marked the front/top with tape and triple checked that when I read in the DIY thread that someone had re-installed it backwards and couldn't get the car to idle correctly.

It's probably a vacuum leak from too much torque. I'll spend the $20 for the wrench, replace the metal gasket that I've probably bent and thank you for the advise.

Carbuff

FWIW Harbor Freight has torque wrenches on sale for $10 USD.


They may not be the best, but at least you can be assured of EVEN pressure which is what you want.

+++++++++

I didn't clean the separate EGR valve on my '99 the last time I cleaned the IM passages. No issues. No change in MPG.

Did you replace the IM - to - throttle body gasket?

I used the EGR cleaning procedure in TSB 00-004 dated December 2001, BTW. That says to replace the EGR valve, but I didn't touch it. (PM me if you can't find that procedure.)

01tl4tl

yes there are details missing from the diy, as we have found more things to do beyond acura suggestions

the info gets put in a thread post, but has not been compiled into a new diy
we still use pics of a 99!! all later manifolds are different than 99~

bolts probably too loose on manifold causing vac leak

service TB while its off the car too

01tl4tl

you have to bring the torque up slow and even on the bolts so its spreads the load outwards from the center and compresses the gasket

meaning= hand tight all, then tool set to 12 lbs all bolts- then 16- recheck all after letting sit 15 minutes
again, its start from center and work outwards, across angle to next bolt, working to ends

mrcombs

Okay... Got a torque wrench and my "torque by feel" method resulted in some pretty inconsistent measurements on the 12mm nuts and bolts across the top of the IM. Removed it and checked the IM gasket again and there doesn't appear to be any damage to it. Confirmed it was installed correctly. I didn't remove the EGR Valve. It does not appear to be original equipment. Way too shiny compared to other components. I'm guessing the previous owner had it swapped out when he had the port recall work performed at the dealer. Plus, I didn't go buy an EGR gasket so I just left well enough alone.

Reattached and torqued as instructed, working the inside-out/incremental pattern suggested. All tightened to 16 ft/lbs now. No noticeable change in idle or response at first glance.

I'll fill up with 93 octane and check mileage again adding another can of Seafoam at half-full to see if there is a difference. Stay tuned... and thanks guys.

01tl4tl

if you didnt remove the egr valve and clean the ports under it to the passage that's supposed to be cleaned from one end to the other...

its coming off again to be done right~

are you cleaning the TB air plate too? carb cleaner will usually get it- otherwise old toothbrush works great

twill220

what r they referring to when they mention tl-p. what does the p stand for and how to determine if it is a p ....also, how much is mpg increased when using platinum plugs as opposed to non-platinum plugs

xtremex626

iTrader: (1)

tl-p = tl premium (base model), tl-s = tl type s (sport model)

check under the hood.. you can tell by the engine, badges, manual, interior, etc.

01tl4tl

your plug choices are
ngk Iridium IX (suggested)
NGK Iridium (fine too)
or NGK Platinum which were stock
(denso brand approved but cost more and last fewer miles)

type S engine uses a different heat range

the plugs run about 8 dollars EACH! - dont try to use anything else or you will be repeating the job in a few days to a month- after posting how bad car is suddenly running,,, even with your `2 buck chuck specials` new plugs

Carbuff

My '99 came with Iridium plugs from the factory.

And 8 bucks is a good price for Iridiums. I think the dealer prices are $13 - 15 bux EACH now.

01tl4tl

who buys plugs at the dealer!!-
they are the exact same NGK you get at oreillys or similar place in town
they may be 10 each now

01tl4tl

99s had a lot of their own stuff compared to 00+
different intake manifold-egr port system, different trans,,irids...