Rough Idle/Sputtering/CEL/Misfire = Coil pack problems (4 Viewers)

[NearJetties]

I picked up Techstream with an obd2/usb cord— it was one of the pricier ones on Amazon ($57) but the installation was smooth on my 64-bit Windows 10 laptop. Splurged since many forums noted issues with newer laptops. The seller was quick to respond with download links since I have no CD drive and the product key. supplied instructions were spot on. First time I’ve needed it since buying the 100 in June and putting 8k miles on it.

After scanning in more detail I installed two Denso coilpacks in cylinders 3 and 6 and the 100 is back in business. I think six was the main culprit but wasn’t going to fiddle more since it was cold, dark and I was working outside.

all the resources in this thread were great.

 

[boofaz]

I was chasing the idle stutter rough running issue for a while and it ended up being the seal around the injector on 3 and 6. Replaced all of them and it’s gone (for now)!

 

[Wooly T]

Sorry all but I've been scouring all the threads and my issue still persists. I'm getting a cylinder 7 misfire and I just changed out all the coil packs last year. So I moved 7 to 1 and the problem stayed at 7. So I know the coil pack is good. Checked the spark plug and it's as clean as a whistle. Checked resistance of the fuel injector and it's well within the acceptable range, measuring at about 14 ohms. Checked voltage on the plug coming from the harness and I'm getting about 14 VDC. I'm pretty lost at this point and I need to smog the rig. Am I missing anything else?

 

[morganism]

seperate ground wires on each coil pack? bundled at a bolt on the block?

try retightening the computer case ground wire from the case to the body.

 

[94SRUNNER]

Sorry all but I've been scouring all the threads and my issue still persists. I'm getting a cylinder 7 misfire and I just changed out all the coil packs last year. So I moved 7 to 1 and the problem stayed at 7. So I know the coil pack is good. Checked the spark plug and it's as clean as a whistle. Checked resistance of the fuel injector and it's well within the acceptable range, measuring at about 14 ohms. Checked voltage on the plug coming from the harness and I'm getting about 14 VDC. I'm pretty lost at this point and I need to smog the rig. Am I missing anything else?

Did you ever resolve this?

 

[Wooly T]

Did you ever resolve this?

Unfortunately not yet. I managed to replace 4 (balanced) injectors from eBay on one bank and the misfire was worse. Now I'm going to put the original injectors back in and start from scratch.

 

[Wooly T]

seperate ground wires on each coil pack? bundled at a bolt on the block?

try retightening the computer case ground wire from the case to the body.

No luck with that either...

 

[boofaz]

Fixed mine with a trip to the mechanic who found a bad seal around the fuel injector. Replaced all seals and now it runs fine.

 

[Chaser717]

Great forum! Had a bit of shuddering in the engine, and the CEL lite up with the VSC lights and all.. code scan read a misfire on the #5. I put in a new Denso coil, cleared the codes and no more codes. Runs fine now. I noticed the coils in there were not Denso so that’s my next project is to replace all of them with Denso. Had her for a couple of years now, LC100, 240k miles. Thank you!

 

[Josey1972]

I replaced all of my coil packs. I still have misfire in 4 cylinders. I have swapped coils and still those 4 cylinders. The VSC stuff has gone away but it still shows the codes and idles like hell. The 0300 code now has me wondering about injectors. The PO rarely drove it in his 6 years of ownership so I wonder if the injectors just got gummy from lack of use. I might change the plugs but plugs seem to have little to do with the symptoms I have.

 

[El Cid]

Word of warning about replacing coil packs. They attach down in the cylinder by the rubber attaching to the bolt(or whatever is inside).
It's highly likely that the coil pack you are removing is old, the rubber has degraded and can likely tear. So here is my suggestion.

Be careful about simply pulling the coil pack directly out from the cylinder in which it sits. My suggestion is to spin the coil back counterclockwise, clockwise a few degrees and make sure it has detached from the connection inside BEFORE you give it a tug.

This probably won't affect anyone, the coil pack can often just be yanked out of the cylinder in which it sits, but this will prevent the rubber from tearing and staying down in the cylinder while the rest of the coil pack has been removed.

Better to be on the safe side, twist a bit first and then remove.

 

[lstamatis]

Just wanted to say thanks to all the contributors. This thread helped me out.

 

[kevin2i]

Need to mention - besides
P0300- general
P0301 - coil #1
Etc.

A P035x code might signify bad coil too.
My 2004 a bad coil threw several P035x codes due to a bad coil. When I took the bad coil out of the 2004 and put it into the ‘98, it throws the P030x codes.
2004 codes:
P0351 - coil 1
P0352 — etc.

Note the 04 popped multiple codes when only one coil was bad. Might have been shorted out (vs open circuit) because the bad coil instantly threw out 2 bad coil codes and a P1300 on the ‘98.

OBD circus P0351 P0354 P0356 P0357 P1300 P0301 P0302

Just did a timing belt/starter/valve cover update on my 2004. Started it up, everything was fine. Started it up 15 minutes later, let it idle for 10 minutes and it started running very rough — OBD gave me these codes: Couldn’t believe I blew 4 coils - I pulled of #1 and swapped it with into my...

forum.ih8mud.com

 

[JeffinSeattle]

As always...GREAT Information - Replaced coil in my 2000 LX with 210k miles in the hopes that it wold take care of 0302 error and it worked great.

This error come up a couple of weeks ago intermittently - I replaced the spark plugs (been a little ofer 200K) and unfortunately that did not take care of it.

Ordered the replacement coil form Amazon last night - It showed up this morning and became it was cylinder 2 it took me no time.