btran

I've got a 02 TL and the check engine light is on and sometimes flashes. It's throwing a 1399 code and random misfires. For the most part it's running fine, but when I start the car it's rough and if I'm stopped or have a/c on. I've already changed all spark plugs, new EGR, pulled manifold and cleaned it good and cleared EGR ports. Acceleration is really good and it's even quicker than it was before, but at starts, stops, and when a/c is on it's rough and check engine flashes. What's the first thing I should check?? Inspection just went out and need to get it fixed as soon as possible and I'm on limited funds.

musiclevelz5

Have you checked each coil pack to see if one is bad?

When engine is running poor, disconnect each coil plug one at a time. If the engine speed does not change then that corresponding coil pack is bad.

btran

I did check when I did the spark plugs, but maybe I should check again. It's giving misfires for all 6 cylinders, but only runs rough when at idle and when a/c is on. Otherwise I can get on the gas and it'll open up a scream down the road.

01acls

When you say "Rough" do you mean missing or rough? Is the car actually missing or idling rough? Rough as in low idle?

btran

It doesn't seem to be missing, especially since I can step on the gas while already moving and it accelerates very quickly..faster than before. It idles rough on the start and when I put in reverse to back out. Sometimes there is some hesitation.

btran

This is where the idle was just now, but wasn't idling as bad as usual. The cel was blinking when I took this.

01acls

When the motor is running rough, open the hood and put your fingers on the motor at the aluminum intake manifold/plentium and feel if the motor is missing or just idling low. Igor what it sounds like. Go by touch only. If its missing the motor will shake. If it's low idle it's still smooth to the tough. Do this at idle and at 1000 rpm if possible (have another person press on the gas).

If it's low idle check to make sure you have good contact at the battery for both positive and negative. Clean the terminals/grounds. Check your air filter make sure not plugged up. Clean your throttle body and air flow sensor.

If it's missing unplug the coil packs one at a time to see if the idle doesn't change. If you unplug a coil pack and the idle doesn't change then that coil is defective... replace it. Do this to all 6 coils.

01acls

Hesitation as in takes a long time for trans to engage or as in rpm doping? Was hesitation there before you did all the cleaning in #1 post?

Skirmich

What about your IACV? A stuck IACV can make a lot of crazy issues...

01acls

Your hesitation could just be an air leak somewhere on the intake manifold. Spray some throttle body cleaner sparingly where any hose is mounted to the intake manifold/throttle body area. If the rpm rises there is an air leak there. I would start where you've disconnected something for cleaning, whether it's a hose or a gasket.

Chojun

If there isn't power loss on the throttle then I'd echo Skirmich, your IACV is probably in need of cleaning.

01tl4tl

when you cleaned the EGR system, you removed the intake manifold from the engine and placed it on a work bench- correct?

what did you do with the TB Throttle Body assembly while you turned and moved the manifold around? was it still attached to the manifold?

the IACV is located inside the bottom of the TB, have to flip it over- remove cover- remove iacv rod, and clean rod and chamber it sits in

01tl4tl

another trick: the top most gasket of the cover assembly to intake manifold-
the gasket can be installed flipped UP side Down! ooops
fits,,, but blocks an important port, must align gasket holes with top cover, not the manifold side to confirm correct position

btran

Ok, so with the car sucking up gas as if it never had gas before, and really rough idle and a few misfire codes (it's somewhat ok when I get up to speed and opens up) I went to take the IACV off to check and clean since I'm sure it's got a lot of carbon in it judging from all the build up I cleaned out of the manifold and EGR ports (I installed a new EGR Valve). I was trying to attempt to just take the IACV with out having to take off the whole throttle body, but the back screw is hard to get to and I put my phone under it to take a pic of the screw to check it's status as of seeing if it was stripped out, and it looked like it was starting to so I didn't attempt. So, then I decided I would take the throttle body off. I disconnected all wires and the four bolts holding it on. The throttle body wouldn't budge so I didn't force it, as I didn't have a spare gasket with me because I'm sure when I get the throttle body off it will need to be replaced.



My question is:



1. I'm going buy a new gasket and for throttle body and IACV. Is there any particular brand that is recommended?



2. The throttle body isn't coming off easy at all. It seems stuck, so what is the best method of getting it off?



3. If the IACV is salvageable as in to working properly after being cleaned where can I find replacement screws? I'd like to put in new screws since one of them looks like it's starting to get stripped out.

01tl4tl

the hardware store will have the same screws, just ask for help
Its way better to work in the TB/IACV on the workbench
If you moved the manifold around with TB attached- need to go in the iacv!

A rubber mallet usually gets the TB free. Sometimes a block of 2x4 tapped with mallet breaks the bond

Yes!!! have a new TB to manifold gasket on hand to replace, may require razor blade to scrape old gasket
iirc there is one on each side of the insulator,,Gurus does he need 1 or 2 TB gaskets?

Plan on IACV `COVER plate` gasket, it may survive- but wont if you don't have a fresh one at the ready~

Look for those at dealer or parts store in town

NOTE: It is possible when doing egr cleaning job- to install the top most gasket= for the cover- UP SIDE DOWN -it fits and will run but blocks a crucial port!
Match gasket to cover to be sure all gasket openings have a mate on the cover
Worth cking that now, and clean IACV

when iacv is dirty = it usually makes the engine surge rev 800-1500 and drop to 800 repeat repeat, stoplight finally changes to green and the car takes off!!
but any crud buildup will lessen the smooth motion adjustments it must make at idle

Always suspect the last work done to the car,,
correct spark plugs? those are critical!! any gasket leaks, vac leaks, coolant hose switched with vac line at TB during manifold installation? All these things happened to members here

01tl4tl

please verify-
you removed the intake manifold from the engine -not just removed the top cover- to clean egr passage inside with 3 cans carb cleaner and a wire coat hanger= to poke the length of manifold, from big opening end to the ports under egr valve
DIY time at casual pace 1.5 - 2 hours
NOTE: Torque spec on the bolts that get removed inside manifold= that hold it on/down is 14-16 foot pounds
Its a good idea to ck those again after 500 miles, some found to be 1/4 turn loose! its a heat expansion issue manifold bolts go thru

random misfire codes is still likely to be 1 failing coil ,,maybe 2 in worst case scenario
Easy to figure out which one - see post by skirm and others for that

Have you have the codes ckd? that will help us-
codes are clues, not a diagnosis in themselves,,we combine with findings and experience to reach best guess!

01tl4tl

Good call on taking cell phone pics of areas you cant see!
Document what things looked like before you take it apart and in steps.
The capabilities of these camera phone things amazes me, Zoom, scroll - bright LED flash = nuthuns hiding in there now!

Been doing that on my motorcycle: to look inside mass amounts of cowling hiding wire tie clips and bolts, someone's previously dropped/lost tool~ bonus for me!