Hey guys, I know this has been posted 100+ times, but here goes. Right now my engine is idleing kinda rough, and misses thoughout the rpm range. It has done this in the past, but lately its been getting worse, the popping noise in the exhaust is pretty consistent. Also, when I start the car up when cold the rpms will shoot up to ~2K then fall back down to normal. Today I replaced my spark plugs, which didnt seem all that bad, just a little carbon on them, but no fuel smell. My timing is stock and I run 93 octane. I have also done a compression check and all the cylinders were equal. I checked all the vacuum lines that I could find an none of them were cracked. My only though right now would be the O2 sensor, since my gas mileage isnt anything to brag about (~24mpg highway). I'm just not sure that this would cause the engine to miss. Anyone have any thoughts? Thanks!

- Brad

 

maybe OHM the injectors and maybe the coils? you should be getting wayyy better mileage than that. I am and I dont even have the y-pipe or UDP

Maybe its the O2, I'm not to sure though.
All I know is all of my coils and injectors ohm great, I'm running BKR5E-11 V-Power coppers, and my O2 sensor has "been threw hell"

When I'm listening to the exhaust (at the tailpipe) sometimes I get a little spudder or puff kind of noise, but aside from that my car idles great, infact now just sitting in the drivers seat, its almost impossiable to tell the difference between when the VTC's are grounded and when they arent. It wasn't always like that, I guess it just took some time to adjust.

on a side note, a friend of mine's car used to make the little spudder noise in the exhaust (sounds like a small mis-fire), but ever since he retarded the timing it stopped.

 

Thanks, I'll try checking coils + injectors tomorrow. Do you know what the resistance is supposed to be through them? I think the injectors are 1.2 ohms, not sure on those either though.

 

24mpg? id kill for that
i get lucky if i get 18mpg damn

 

"My only though right now would be the O2 sensor, since my gas mileage isnt anything to brag about (~24mpg highway). "

mine is about 20 mpg, is the O2 sensor the main thing that makes it such low mpg?

my idling isnt as good either, the exhaust makes rapid puff puff noise and sometimes, especially when in reverse gear (automatic) it sounds like its about to die

 

Get the car warmed and idling. Start disconnecting one coil plug at a time. If it idles worse, it's probably okay.
If it stays the same, it might be a bad coil or plug. You can swap coils to see if the problem moves or stays. If it stays, then swap plugs and repeat.

 

did that, they work allright, but the spark seems weak. im thinking cople of the injectors cause the prblm.. same thing could be for Brad's

 

Mine was idling really rough and stalling on hard acceleration, but I had a cracked front coil. Replacing that seemed to help the idle. I still had the stalling problem, but I replaced all three rears and that stopped (so far).

I grounded my VTCs and now it seems to idle a little rougher, especially when cold. It also will diel on occasion when I push the clutch in. Yesterday, I put the VTCs back (ungrounded them?) and the idle is better cold and it hasn't died yet. Of course the VTC ticking is back, too.

When I came back from MrGone's house (four hour drive) I got around 28 mpg, and I was going 75-85 the whole way. I do have a y-pipe.

 

Both Shawn and I have experienced a bit smoother idle buy installing our ground wire kits. We did his yesterday. He seems to like it. But you know him! heh

 

brad i'm having the same problem, except i've tested EVERYTHING, and i have a VERY inconsistant idle. the only things it could possibly be are O2 and timing. i made a thread a few weeks ago, lots of good info in that as to what my problem isnt
hope you get it figured out.

 

You haven't timed it?

 

Yeah, I hope I get this taken care of... I'll try to ohm the coils and injectors tomorrow. AS for unplugging, I dont think its a bad coil, since there is no stalling, but I unplugged the #5 coil and the idle did not change very much. However, when the engine was revved up I could tell a definate difference. I dunno, maybe I'll check the O2 sensor.

 

http://garage.digitalbeta.net/images/ohmspec.JPG

 

not since the motor went in. i marked where it was before i pulled the motor out, put the CAS back in. then i kept messing with the timing, the marks came off..i'll time it before i drive it again. for whatever reason i HIGHLY doubt its the problem. VE guys i've seen run anywhere from stock (15BTC, right?) to ~25 (candiman?) i dont see what difference it makes in consistancy if its anywhere in that range.

 

Ok, today I checked the resistance on the coils and the front injectors. All of the coils are around 1.5 ohms. The factory specs say 0.8, but it doesnt seem like they would all be bad. The front injectors were within spec, two of them at around 12.5 ohms and one at 13.4 ohms.

 

I had injectors that turned out to be intermittently bad. If you can pull the injector plug off while the engine is running, it won't change on the bad injector. I had these guys test and clean my injectors, they did a great job for the best price you'll find anywhere: http://www.fuelin.com/index.html
If an injector shows intermittent good then bad, ditch it. I had one, put it all back together and everything worked great for one day till it started screwing up again. I replaced it and Voila!, All fixed. These are definitely a wek point for this car, pricey too. Good luck.

 

A little update: Whenever I start the car when its had a little time to sit, it will run as if it were on 5 cylinders, both at idle and driving. This goes away in around a minute or two. It pretty much sounds like its running with an unplugged coil. This started happening after unplugging the harnesses of the coils and front injectors to ohm them, and I'm positive I plugged everything back in. I'm starting to think more and more that it could be an injector, but I really hope not. It's only been doing this for a day, so maybe it will get better.