DTC Codes P0171 P0174 P0301

[lesgarten]

Gotta rough Idle and these 3 codes on a scanner.

Cyl #1 Misfire
Lean Bank 1
Lean Bank 2


I swapped the coil out on #1 and no change there. I was going to check MAF next, assuming there is a MAF.

Car has 124K 2002 LC
Plugs are Denso and have about 4K. Just went thru timing belt change 4K ago.

Any Magic Bullets out there for this?

Thanx!

 

[packer]

Have you checked this out?

https://forum.ih8mud.com/100-series...puttering-cel-misfire-coil-pack-problems.html

 

[lesgarten]

Have you checked this out?

https://forum.ih8mud.com/100-series...puttering-cel-misfire-coil-pack-problems.html

I replaced the coil pack. Also read a number of those posts.

 

[Trunk Monkey]

You swapped in a new coil or put coil 1 on another cylinder?

 

[lesgarten]

You swapped in a new coil or put coil 1 on another cylinder?

I put a new coil in.

 

[packer]

You could try swapping some of the original ones around to see if the misfire migrates.

 

[lesgarten]

You could try swapping some of the original ones around to see if the misfire migrates.

Maybe a "fun" thing for tomorrow! Only way that would happen though is if the "NEW" Coil was bad also though.

 

[packer]

Maybe a "fun" thing for tomorrow! Only way that would happen though is if the "NEW" Coil was bad also though.

See: https://forum.ih8mud.com/100-series-cruisers/348172-random-misfire-code-po300.html

thread also has some spec's to test with a DMM

 

[lesgarten]

OK Update, and more questions

The coil was not an issue. I moved coils around. Ohm'd out the coils, no change in problem. The problem is at idel, rough idle and throwing coeds related to misfire an lean on both banks.

The car feels fine once it gets off idle. I cleaned the MAF sensor, and checked the plug on that cylinder. The plug is burning perfectly. The gap is fine and the plugs have 8000 miles on them. They are Denso Iridiums.

My wife tries to drive it today and CEL comes on as well as VSC Track and VSC off. I pulled codes and got more codes

P0301 Cyl 1 misfire
P0171 System too Lean Bank 1
P0174 System too Lean Bank 2

P0302 Cyl 2 Misfire
P0130 O2 Sensor Circuit Malfunction Bank 1 Sensor 1
P0133 O2 CKT slow response Bank 1 Sensor 1
P0150 O2 Sensor Circuit Malfunction Bank 2 Sensor 1
P0153 O2 CKT slow response Bank 2 Sensor 1

I'm curious how both sensors start having issues at the same time?

The Cylinder 2 misfire only shows up every once in a while.

So the coil can go back. The VSC lights come on when there are enough impairments to the motor that applying the VSC would make it sicker from what I read. So the VSC gets disabled.

I would hate to buy two new sensors and put them in and have that not fix the problem.

Any suggestions?

 

[cmfhsu]

Do you have any other electrical gremlins? Try testing the battery. A dead battery can do funny and unexpected things things to a car. I once had all of the lights on my dash light up simultaneously, and the problem ended up being the battery.

 

[lesgarten]

Do you have any other electrical gremlins? Try testing the battery. A dead battery can do funny and unexpected things things to a car. I once had all of the lights on my dash light up simultaneously, and the problem ended up being the battery.

Nope, I'm going to get some starting fluid tomorrow and hunt vacuum leaks. I'm going to order a REAL scantool also, one that will give me live data like voltage on my sensors and what not.

 

[Brian Anderson]

Hey did you finally sort this issue? I have basically same codes. Rough idle, runs great. CEL on and those codes. Hoping you had a diagnosis to share ??

 

[DenverLX]

I have this same problem, any solutions