watson6505

Everyone, I have read other threads on similar topics, but I am hoping I can get some consolidated advice in a new thread. I've got a 99 TL with 170k and a couple days ago it started idling rough at low RPMs and the Check Engine and TCS lights both came on. It seemed to still run Ok at mid/high speeds with no real hesitation or performance/shifting issues. So I took it over to Autozone and got the following codes spit out:

P0301 - Cylinder number 1 misfire detected
P0302 - Cylinder number 2 misfire detected
P0304 - Cylinder number 4 misfire detected
P0305 - Cylinder number 5 misfire detected

Probable Cause:
- Vacuum leak affecting cylinder
- Ignition System
- Blocked/Faulty fuel injector
- Engine mechanical condition

P1399 - Random cyclinder misfire detected

Probable Cause:
- Blocked EGR passage
- Valve clearance out of range

Obviously with the age/mileage of the car I dont want to take it to Acura and drop $1000 in diagnostics and trial and error.

I'd like to know what the forum thinks is the best course of action for these codes.


Thanks

fsttyms1

Typically the random misfire on these cars is just 1 single coil pack that is the cause. Does it always run rough at idle? You could try unplugging one coil pack at a time and see if the idle changes. If you inplug one and there is no change that is your problem. You could also buy 1 new coil pack and replace one at a time and see if it fixes the issue (the route that most take)

Have you ever had the EGR port cleaned? You may want to look into that as well.

Also i would Try running some good fuel cleaner like Seafoam.

3.2TLc

^^^ Yeppur....totally agree with Fsttyms1.

~ First, try some quality fuel system cleaner.....then clean the notorious EGR passageways and TB intake.
~ If it's been awhile, try a tune-up using NGK plugs and a new air filter.
~ Check all electrical and vacuum lines. The grounds are critical along with no vac leaks.
~ Clear the codes and then if the random misfire codes pop back up, buy one coil and proceed to check them as Fsttyms1 previously suggested.
~ For all kinds of great info, check out the "DIY" sticky for all sorts of common issues and fixes.

watson6505

Thanks for the feedback....it never ran rough at idle until the aforementioned dummy lights went on. I actually ran sea foam through a couple months ago because the wife said it would not start. After that it seemed to start no problem and no problems since then.

I think I am going to start with the egr passageways since that is primarily a labor only option (plus cleaner).

Is there a good DIY or tutorial for a 99 TL? I saw one on you tube that was for a 2000


Thanks again

01tl4tl

the 99 has only 1 egr port to clean- 6 on later years, it should contain a smooth cylinder in the egr hole, installed under recall- clean pathway thru length of manifold

buy 1 coil and find where its needed, how old are the spark plugs? use 8$ each NGK
clean intake manifold and egr system
run seafoam at 1 can to just under half tank of gas, do that twice
should purr after those fixes

note clear codes/ reset ecu by removing CLOCK fuse on passenger end of dash for a minute and reinsert, After new coil installed- clear codes and it will run a full self test

01tl4tl

how is the battery? wife said it wouldn't start- what did you do then- jump?
low volts will throw many false codes and make car run poorly
auto parts stores are happy to run a machine test for you for free

watson6505

sorry, by 'not start' I meant it would not turn over...cranking was fine.

3.2TLc

Hey Watson6505, ya may wanna consider having the electrical system load tested. Check the battery connections and especially the grounds. Our cars get real finicky if they don't get their juice.

For lots of great info on common issues and fixes, check out the "DIY" sticky !!!

00TL-P3.2

Thanks for the coil check tip. Mine has had this issue for a while.
I've figured out how to keep it from throwing codes/running terribly. Pretty much have to let it sit for nearly an hour to cool down & it starts fine.

Will try to unplug a coil at a time & see if I can narrow it down. Rather buy 1 coil than 6 if possible.

3.2TLc

^^^ May also want to check the PGM-FI main fuel relay, as they are known to cause some problems.

01tl4tl

doh! beaten to the follow up answer by 3.2 again!!
the dreaded FPR, been a few of those recently too, fits the description of hard to hot start

buy 1 coil aftermarket is fine if beats dealer price, do the `remove power lead one at a time`- no rpm change mean dead coil,
3.2 is that engine OFF between pulling power lead to coil?

install new coil and do ecu reset by clock fuse method

Now I am really confused!!! "sorry, by 'not start' I meant it would not turn over...cranking was fine.
turning over is the engine cranking!
not starting = engine cranks/turns over but does start and run on its own

so how did you get it started that time? and why havn't you stopped by local parts store for batt and charging system test its FREEEEEEEEE

3.2TLc

I'm sure that people have checked coils by various methods, but Fsttyms1 may chime in to offer details on his preferred way to check for a dead coil and any risks involved.


Yeah, didn't quite follow Watson6505 's starting issue either.
Perhaps wifey ? ...... sorta find it difficult to believe that Seafoam cured that.
Some more details may be helpful.

01tl4tl

seafoam can be used as a starter fluid for the engine!!, but difficult on the TL without removing air intake snorkel

watson6505

OK, so I cleared out the EGR passage and throttle body. The passage was definitely showing some clogging, but it had already been in for the bulletin since the modified pipe was in place. I expected it to be dirtier but I've never done it before so I was not exactly sure what to expect. All back together, then a battery disconnect and it's still running rough at idle and the light came back on after about 5-7 minutes of running.

To the earlier question, the car would crank just not start. So a few hours later I got some sea foam from PepBoys and when I tried to start it it did start and no problems since. That was probably 2 months ago.

I want to try the coil route. Someone said something about 'the risks and preferred way' to check coils. What are the risks? What is the preferred method? Is any coil wire sufficient? Is an 18" long enough or should it be a 30" or some other length?

Thanks for the help everyone

watson6505

OK, looks like people are talking about changing the coil and not necessarily the wires.

3.2TLc

While a random misfire code can be caused by many different things, the most common thing is a bad coil as Fsttyms1 previously stated. Usually it's only one coil and will cause the motor to run rough.

An easy way to check for finding that bad coil is to simply remove the electrical connector from it's coil while the motor is idling. If when the connector is unplugged......the idle gets noticeably worse.....then that coil is good. Plug that connector back in, then move to the next coils and do the same thing one at a time, until you find one that does not change the idle.....staying the same.....would indicate a dead coil for that cylinder.

After shutting motor off, remove the coil pack's retaining allen hex screw, then check that cylinder's plug. If ya have a new coil, replace this particular coil with it. If ya don't, try swapping a coil from the opposite side and then restart the motor and see if the dead coil caused the other side's swapped coil position to test bad.

To reset the PCM, remove the #13 CLOCK BACK-UP FUSE (7.5a) from the lower passenger's side interior fuse panel. Wait a minute, then put the fuse back in. The CEL should then be reset and the light will go out.

watson6505

Thanks Tlc, I went about the test a little differently because I found the electircal hookups to be a little difficult to unhook quickly (especially in the back). So using the allen hex screw I unscrewed all the coils and started the engine. I then pulled them one by one and the first 5 made a noticeable difference in engine idle. When I removed the 6th one (worst location back left) there was no change in engine idle. I turned the engine off and swapped that coil for another coil to see if the plug was OK and the back left cylinder fired as expected, but the front one now didnt fire. I'm assuming if I replace that coil its a step closer to being fixed.

I'm headed to autoparts now to pick up a coil.


Thanks again to everyone...I will provide an update

3.2TLc

Yeppur, pretty sure that was also the same position which I had to previously replace a coil on. Never get lucky on the front. Make sure that the existing plugs are NGK's. Our TL's don't like the off brands !!!

01tl4tl

did any/some/all 99s have single coil with actual spark plug wires?
all later years got 6 coils and no spark plug wires- coil sits on the plug
thats one reason we need the special high dollar plugs = high energy ignition

for single coil system use multi meter, or expect failure at this many years in service

If I found 1 bad coil on 6 coil car, replacement of at least that spark plug is in order
its been running poorly, a new plug will use all the power of new coil.
If its been more than 70kmiles since plugs- time for all new ones
compared to the ever-rising cost of gas, the payback for 50-60 dollars for plugs (includes can of seafoam to remove carbon from offending cyl) and an hour of your time is money well spent

watson6505

I did not replace the plugs at this time because I did confirm that plug was still firing when putting a working coil on it. I'm going to give this a couple days/weeks to ensure there is not another lingering problem that was being covered up by the bad coil. So far so good on the new coil, no more rough idle, no more engine lights. Clean throttle body, clean EGR passage, new coil, $43 spent. Acura wanted $90 just to diagnose the problem and who knows what they would have charged me for any repairs.

BTW - there are like 10 different types of ngk plugs, which ones are recommended and do they come 'pre-gapped' or do I need to do that?


Thanks again!!

3.2TLc

Good to hear that the new coil helped !!!

* The original factory OEM plug used was NGK: PZFR5F-11 Platinum.

* With the more recent technology, most folks opt up to the newer Iridium or Iridium IX NGK plugs.
They come pregapped at 1mm/.040" spec gap.

* When ya decide to replace them, here's a helpful "DIY":
https://acurazine.com/forums/2g-tl-1999-2003-98/spark-plug-replace-change-diy-760163/
Be careful when removing and handling the fragile coil packs.

01tl4tl

while the spark plug will still work after a bad coil- the idea is leftover unburnt materials clog the top of the piston- which increases compression (not ok) leaves deposits on plug firing tip, and reduces overall burn efficiency in the chamber
that's where the seafoam comes in for cleaning!

but 1 new plug will be a good idea and easy to reach once the coil is already removed.

I dislike doing labor twice

01tl4tl

the 8 dollar each ngk iridium, iridium IX or Platinum (slightly higher price) are all good for the TL. don't need the LAZER welded NGK
do not use bosch acdelco or other 2 buck chuck plugs- unless you like replacing spark plugs again with the correct ones
denso are allowed but cost more and last fewer miles based on ziner reports

I know the book says 100kmiles for plugs,it also says about half that if driven on Earth, the severe service schedule