Roblee23

I noticed a while ago, that my car would idle dead smooth and really has hardly any vibration while it was idling cold, but when its warm and after driving a bit, theres noticeable more engine vibration trembling the steering wheel a bit, its still still smooth, but not nearly as smooth as it idles when the engine is cold, i would think it would be the other way around. Btw, i know for a fact im due for new plugs, i also think the iacv, egr, and throttle body should be cleaned also, has anyone experience something similiar?

thoiboi

Yup clean all those listed. Many threads citing those will fix your same problem.

Roblee23

Cool! Cant wait to get it done.

Roblee23

I have been hearing that its best to seafoam the TL before new spark plugs, its cold and snowing here in chicago, so i probaly wont be able to do it until maybe april lol, or i can always pay a shop, but i dont paying somepne to do things i can easily do on my own. So my next question is, if i seafoam my car now will it smoothing out the idle a little and improve throttle response? Im thinking of doing sometime within the next couple of days, I hate the vibration in the steering wheels, but that laggy ass throttle response REALLY bugs me. I didnt think i needed to clean any internal parts because the car isnt throwing codes for the egr and i only have a little over 114k. Thanks.

indybob67

Hi,

Had a similar issue. It only happened when it was warm. Especially worse in the summer. Talked to a mechanic and he recommended replacing the coil pack. (The coil pack is what you have to remove to change your spark plugs.) Problem he said was figuring out which one since the problem is intermittent. He recommended changing the 3 rear ones and keep the old ones as spares just in case the problem came back.

So after changing, we numbered the old ones 1,2,3 and the ones on the front got letters A,B,C. After a short while, guess what? Problem came back and I swapped A with 1 and since then the problem has been solved. If you are on a budget, I'd suggest getting 1 coil pack, replace one of the rears and see if it solves your issue. If not swap it for the next, and so on until you solve your issue.

My car had 275K so we deiced to do 3 on the slight chance that more than one coilpack had gone.

Hope this helps!

Kris9884

Finding out which coil is faulty is probably the easiest problem to diagnoses in the world. Unplug each coil one at a time while the car is idling, the one that gets unplugged and doesn't change how the car idles is the one that's faulty. This takes a maximum of 2 minutes in your driveway and completely free.

Roblee23

​​​​​ correct I've used this method the last time 2 coils went bad

indybob67

I agree that if it is a constant problem the best method to find out which one is the problem is to disconnect one coil at a time, and remembering to only do so when the ignition is off. However, the problem described seemed to be intermittent, which mine also was, so it was harder to tell which pack was bad. I'm not a mechanic, but like most folks here, just a car nut and like to do as much maintenance and work on my car by myself. Thanks for everyone's input, and darn the politically correct here in Canada - Merry Christmas to everyone!

Roblee23

i know its not a coil, the only code my car is throwing is p1457, which is a evap leak, car runs great, even though from time to it would idle low and rough on warm start up, sometimes it stalls. I normally start it up and tap the gas pedal and it idles where it should right away. I dont think my motor mounts bad because when its idling cold, theres literally no vibration in the steering wheel, only when warm. I recently did a seafoam through the intake and i resetted the ecm via removing the clock fuse and throttle response is nearly 70% quicker than it was prior, but still not instanious like how i wish it was.

GeezUss

Hey guys (Gals), I'm new to this so please forgive me.....quick question, anyone know if the coils on the RSX Type-S are the same as the TL Type-S? I have an '02 Type-S, and I have just over 207,000+ miles on it and it runs great, but was wanting to upgrade the ignition some. I'm not having any crazy idle problems, for a car with this many miles. I did change the plugs at 200,000 miles, as well as the timing belt, tensioner, water pump, even the oil pump. Anyways, I seen that Accel sells upgraded coils for the RSX Type-S and was just curious if they were interchangeable. I have noticed that the OEM part numbers for the coils on both cars start out as 30520, but the last remaining digits are different (TL Type-S: 30520-P8E-801124, RSX Type-S: 30520-RRA-007).

Any info on this would be great. Thanks in advance!

Roblee23

I just cheked this out, their different. Not interchangeable.

GeezUss

Ok, thanks! I appreciate the 411.

Roblee23

Very welcome!

shamal

Just had this issue on a 99, very well cared for engine. We changed the plugs and it had a bit of a rough idle after warm-up and pcu reset, engine ran well above idle.. Checked everything, it's been seafoamed a few times, upper and lower intake removed and everything cleaned a while back. Turns out #2 coil pack was intermittent. No codes on our Autel scanner etc, no vac leaks. Finally unplugged the coil-packs one at a time and found it. Original coil packs, so will change the other 5 soon. Hope it helps someone trying to diagnose new NGK plugs and coincidental rough idle after warm-up.

curlywurly

My 2002 has 193k on it, I had the same issue as you, and no codes. I checked the plugs and they were worn out, so I replaced plugs, some improvement, I then cleaned out the EGR valve, ports and IACV etc. There was a ton of carbon build-up, the 6 ports looked like they had black plastic washer in them, but it was carbon build-up, the channels weren't much better, I would say that it was about 50% blocked at a minimum. It took at least an hour to thoroughly clean everything and was an easy but messy job. IMHO, with the amount of build-up I saw, there is no way spraying a can of Seafoam would have cleaned it out, if you do it, you will see what I mean!

It also fixed the idle issue, and the car runs much better over all.

BOBSRED40

Seafoam is added to the gas tank, not sprayed. I use it in the winter. Keeps gas stable and helps with the higher % of ethanol.

BOBSRED40

I agree with cleaning the EGR and IACV. They are next to each other and easy to get to. There are very good videos on both subjects. Changing spark plugs if they are due is also a good Idea.

thoiboi

Yeah, after you reset the PCM, the engine will run well above idle as it does the Idle Re-learn..