teamG720

Hi all!

My TL is misfiring after having service done on it. It's kind of a long story but your time is appreciated!

I have a 1999 Acura TL 3.2 with about 87,000 miles on it.

It was running hot at times, so I had it checked out by a shop and wanted a synthetic oil change done as well. They replaced the thermostat and changed the oil. When they had my car raised for the oil change, he spotted a small coolant leak on the head and called me down to look at it. He then put some sealant in to seal the leak. My car now no longer overheats.

But after driving a couple miles directly from leaving the shop, my car was running a little rough in the lower RPMs, my TCS light and Check Engine Light came on. They were never on before and my car never ran like it does now. I took it back and he said "having it running up in the air on the stand could of and triggered the TCS light because of traction control" He reset the the codes they went away and came back as the car ran the same.

I took it to AutoZone and checked the codes they read as follows:

P0301 - P0306 Cylinder Misfire
P0300 - Random Misfire
P1399 - Misfire in any Cylinder

Before I took my car to get maintenance my TCS or Check Engine light had never came on before. Is there something they could of done to trigger this? Also wondering where I could begin to troubleshoot? I know spark plugs but don't know where to go from there if that isn't the fix? Sucks to fix one thing to get another problem.

Any help or insight is appreciated.
Thanks!

fsttyms1

The TCS comes on for many CELs. Having it up in the air had nothing to do with it. You have a misfire causing your issue. It is most likely nothing more than chance that it came on after the work as nothing done should have caused it.

What i would do is remove the #6 coil pack and swap it with something like #4 reset the cel (pull the clock backup fuse on the passenger side dash fuse panel for a min then plug it back in will reset the light) If the light comes back on have the code read and see if it followed the coil pack (common failure on these cars). If it did then that is your problem. If not then we will look into other things


1-2-3
4-5-6
Front of car

teamG720

Thanks for the help, i'll try this and see if it bodes a solution!

So basically, i should see if it pinpoints that coil pack when i check for codes? Because when I had it checked the first it showed all cylinders misfiring.

johnnybegood_5

I recently had the same codes plus some more misfire codes on my TL. It was a bad connection on injector 4, yet the car gave me misfire codes for all the cylinders.

The codes are more of clues to pinpoint the problem.

The multiple misfire code is usually a coil pack gone bad.

while the car is running you can pull the connector off each coil pack and listen for a change in how the engine runs.

If it runs more rough, you know that cylinder is good (is NOT misfiring).

If it doesn't change how it runs, the cylinder is misfiring and thus try replacing the coil pack with another.

fsttyms1

I mis-read your original post. I didnt see the P0301- 306

The ecu on these cars will pick up the misfire but most cases throw a all cyl and you usually have to buy one new coilpack and start replacing each cyl with the one new and resetting the ecu in-between until you locate the bad one. The misfire on this car is 99% of the time just 1 coilpack.

fsttyms1

If your injector isnt operating properly its not spraying the correct amount of fuel causing detonation/misfire due to lack of proper combustion.

That method of chasing a bad coilpack "only" works on one that has completely failed. Many times one is still firing but not all the time that is required causing the misfire.

teamG720

I was thinking bad fuel... should i start with coil packs then check injectors and fuel pump?

3.2TLc

Hey TeamG720, Without knowing any specifics concerning your TL's previous maintenance history other than this recent overheating episode.....I'd suggest starting with your coolant system first. Have the system pressure checked and inspect the entire system for leaks. If it's been awhile, perform a full flush, drain and refill of coolant. The system must be properly purged of any residual air pockets. A Honda 2 stage T-stat is preferred.

Once you are certain that the cooling system is in perfect working order, run some fuel cleaner in the gas and then do a basic tune-up if it's been awhile......replace the spark plugs, air filter, pcv valve, etc. Clear any codes, if the misfire comes back.....buy one coil and do as Fsttyms1 suggested earlier.

teamG720

Hey guys, I ended up finding the bad coil on cylinder 4!

replaced it and it runs pretty smooth!! lights went away, still kinda stumbles in the 2000 rpm range, other than that good!

Thanks for all the help and suggestions!

Should I be worried about the the roughness in the 2000rpm range? I don't know if I'm only noticing it because I've been alert to misfire or not.

3.2TLc

Good job !
A '99 with 87k is hardly broke in, but don't neglect the basics !
It's coming of a time when the 13 years has eroded the newness. Check your owners manual for recommended service, your TL's time has elapsed before the mileage intervals.

Read the "DIY"s and if you're planning on keeping the car for awhile, start doing some PM.
It'll pay off down the road, if you stay ahead of things !