Misfire Codes All Cylinders

[WhitexLegs]

Afternoon,

 

I'll get straight to it. Over the past few weeks I have been trying to diagnose a problem I've been experiencing with my 05 Legacy GT. (~120k miles)

 

The car runs fine taking it easy up to about 40-48 MPH and runs fine when not under load.

 

Physical Symptoms/Issues:

When under load (most reproducible in 3rd & 4th), around 4000-4300 RPMs and 45-50 MPH the engine, as best as I can describe it, seems to just quit. At this point pressing the gas pedal further and even to the floor only results with sputters, bucking and backfires. Something stranger though is that the RPM's no longer climb even if the pedal is on the floor for a brief time and the speed will not go beyond 50 MPH.

 

Recently when trying different fixes before throwing money at it, I tested it again and under constant throttle the car began to surge.

 

 

Error Codes:

I have received misfire codes over all four of the cylinders over the course of my short test runs and a cam position sensor code only once. These codes aren't always thrown and during the problematic moments I described above the check engine light will flash but doesn't always stay on.

 

Things Considered:

- Coils/Plugs (unlikely seeing as misfires have been over every cylinder)

- Fuel Pump (tested it earlier this week and its running just fine)

- Timing Belt (Due for replacement accor. to mileage but not from actual

wear and everything lines up correctly)

- Vacuum Leak (I've tried nearly every hose I could manage to reach from under the hood but maybe I missed some)

-Bad Gas/Dirty Injectors (Used plenty of dry gas and injector cleaner)

-Airflow sensors: (Disconnecting these leaves the car running like shit and throws error codes immediately)

-Both Brake Lights Out - Limp Home Mode (Worth a shot, but they're fine)

+ More that I am probably forgetting to mention as it's been a few weeks now

 

Going Forward:

At this point I'm stumped. I can't figure out just what is wrong with this car but it's been a money pit ever since I purchased it four years ago and I am quickly losing my patience. I keep well up to date on maintenance and I am never hard on this car but it has been a constant source of problems and frustration.

 

UPDATE: (7/13/17 9:20 AM)

- Tee beneath TMIC (checked and it is all set)

- Checked turbo inlet and all plumbing connection excluding wastegate control solenoid

[relative4]

That cam position sensor code may well be your answer. A CPS on its way out can cause these symptoms. What code was it?

 

Have you smoke tested and/or checked the tee under the TMIC?

[MilesA]

If you haven't pulled the TMIC, I would try that next. Check the tee as relative4 said, also check the turbo inlet and the plumbing connections from the turbo through to the throttle body.

 

Did you read any other stored codes? Anything about a possible clogged catalytic converter?

[WhitexLegs]

That cam position sensor code may well be your answer. A CPS on its way out can cause these symptoms. What code was it?

 

Have you smoke tested and/or checked the tee under the TMIC?

 

P0011 and P0021 after sea foam and running the engine. Cleared the codes and they haven't come back after several cycles.

 

Tee beneath the TMIC was fine.

 

If you haven't pulled the TMIC, I would try that next. Check the tee as relative4 said, also check the turbo inlet and the plumbing connections from the turbo through to the throttle body.

 

Did you read any other stored codes? Anything about a possible clogged catalytic converter?

 

Checked the turbo inlet and all plumbing connection excluding wastegate control solenoid.

 

No codes besides and nothing about clogged catalytic converter

[JmP6889928]

Clogged, broken, or loose inside the housing catalytic converters. Car will idle fine but as soon as you put any kind of power to it, it loses any power.

[wpmarky]

subscribed, i'm also getting misfires in all cylinders. My idle is stable, i feel pulsing on the highway with light throttle. I'm guessing it might be the DW850's getting old, but would like to find more info before replacing injectors.

 

I am getting a big gas smell in my garage when i cold start in the mornings, as if i was catless on e85. But i'm catted on 91 pump gas.

[WhitexLegs]

Clogged, broken, or loose inside the housing catalytic converters. Car will idle fine but as soon as you put any kind of power to it, it loses any power.

 

Could you elaborate a little further? I'm not sure a understand completely

[MilesA]

If the catalytic converter is blocked or clogged, you will have a lot of exhaust backpressure. The engine produces a lot more volume of exhaust when producing power on boost. So, the effect of a clogged catalytic converter is to limit how much power your engine can produce. It can also trap heat and cause your engine to overheat eventually.

[WhitexLegs]

If the catalytic converter is blocked or clogged, you will have a lot of exhaust backpressure. The engine produces a lot more volume of exhaust when producing power on boost. So, the effect of a clogged catalytic converter is to limit how much power your engine can produce. It can also trap heat and cause your engine to overheat eventually.

 

Interesting. I haven't received any codes for it but I will try to look into that as soon as I can.

[WhitexLegs]

If the catalytic converter is blocked or clogged, you will have a lot of exhaust backpressure. The engine produces a lot more volume of exhaust when producing power on boost. So, the effect of a clogged catalytic converter is to limit how much power your engine can produce. It can also trap heat and cause your engine to overheat eventually.

 

Won't a clogged catalytic converter affect the rear o2 sensor and bring up a check engine light though?

[Marvick08GT]

Not necessarily.

[MilesA]

Won't a clogged catalytic converter affect the rear o2 sensor and bring up a check engine light though?

A bit of an analogy: You have a top performing track & field athlete. You force him to breathe through a straw. He could probably walk OK, but if he tried to do anything more strenuous he couldn't manage it, even if he was in perfect shape.

 

If your cat converter were clogged, you might expect the car to run rich. You might smell fuel from the exhaust. It could trip a CEL, but not necessarily.

[birdmayne]

I have a 2004 Explorer with a clogged cat. No MIL, no DTCs stored or pending. Full tune up done, cleaned throttle body, replaced air filter, checked fuel pressure... Ran myself ragged diagnosing why it wouldn't hold a load without misfiring.

Turns out it was just a catalytic converter that is clogged. Cut out cats, and the damn thing runs perfect...

[WhitexLegs]

Not necessarily.

 

A bit of an analogy: You have a top performing track & field athlete. You force him to breathe through a straw. He could probably walk OK, but if he tried to do anything more strenuous he couldn't manage it, even if he was in perfect shape.

 

If your cat converter were clogged, you might expect the car to run rich. You might smell fuel from the exhaust. It could trip a CEL, but not necessarily.

 

I have a 2004 Explorer with a clogged cat. No MIL, no DTCs stored or pending. Full tune up done, cleaned throttle body, replaced air filter, checked fuel pressure... Ran myself ragged diagnosing why it wouldn't hold a load without misfiring.

Turns out it was just a catalytic converter that is clogged. Cut out cats, and the damn thing runs perfect...

 

 

Interesting. I never thought about it like that. I finally have some time again this week to check this and I will get back to you all with an update once I do.

[Max Capacity]

There is a cat in your up pipe. you'll want to remove that cat.

 

You'll pull the egt probe too and plug that hole with a bolt from the auto parts store.

 

there is a 2.2k ohm resistor you install with the egt connector is removed.

 

While the down pipe is off check the turbo for shaft play...you should feel none.

 

Might want to replace the oil return hose from the turbo and remove the banjo filter from the back of the head.

 

you have lots of reading to do.

 

 

http://people.csail.mit.edu/ilh/vacation/

[WhitexLegs]

There is a cat in your up pipe. you'll want to remove that cat.

 

You'll pull the egt probe too and plug that hole with a bolt from the auto parts store.

 

there is a 2.2k ohm resistor you install with the egt connector is removed.

 

While the down pipe is off check the turbo for shaft play...you should feel none.

 

Might want to replace the oil return hose from the turbo and remove the banjo filter from the back of the head.

 

you have lots of reading to do.

 

 

http://people.csail.mit.edu/ilh/vacation/

 

I rebuilt the turbo ~10k miles ago (internals replaced along with some hoses and banjo but kept the housing), and I seriously hope that isn't the problem as I am just not in the mood to go through that nonsense again.

 

I'll look into the link once I get out of work and come back soon with an update.

[Max Capacity]

The link to the service manuals is for your general knowledge.

[WhitexLegs]

The link to the service manuals is for your general knowledge.

 

Funnily enough I threw a code yesterday for the EGT. That is my next step

[MilesA]

If your car still has the uppipe cat, that could be what's causing the issue. Subaru got rid of that cat in later years. A catless uppipe from a later model Legacy or STI will fit like it came from the factory that way. Just do the resistor mod.

 

Note: That would be model year '07-'09 OEM uppipe to be specific.

[JmP6889928]

Could you elaborate a little further? I'm not sure a understand completely

 

If the converter is broken or loose, it will lodge sideways in the housing and not allow exhaust to flow through well. I had a Mazda that exhibited the exact same things you are talking about. I punched the converters out and found one that was all broken to pieces. As soon as I removed the pieces, it ran perfectly and had more power than it ever had before.

[WhitexLegs]

If your car still has the uppipe cat, that could be what's causing the issue. Subaru got rid of that cat in later years. A catless uppipe from a later model Legacy or STI will fit like it came from the factory that way. Just do the resistor mod.

 

Note: That would be model year '07-'09 OEM uppipe to be specific.

 

Resistor mod didn't have much effect. I'll have to look into a catless uppipe soon.

[MilesA]

Resistor mod didn't have much effect. I'll have to look into a catless uppipe soon.

You don't need the resister mod until you get rid of the stock catted uppipe.

 

The purpose of the mod is to avoid getting a CEL since you removed the EGT sensor with the old uppipe.

 

You should get rid of the catted uppipe ASAP. That could be the source of your problem with lack of power. If the catalyst material in the uppipe breaks up, it can damage the turbo and that can lead to serious engine damage pretty quickly.

[WhitexLegs]

You don't need the resister mod until you get rid of the stock catted uppipe.

 

The purpose of the mod is to avoid getting a CEL since you removed the EGT sensor with the old uppipe.

 

You should get rid of the catted uppipe ASAP. That could be the source of your problem with lack of power. If the catalyst material in the uppipe breaks up, it can damage the turbo and that can lead to serious engine damage pretty quickly.

 

Apologies for the absence. I did the resistor mod first simply to see if by some chance it helped anything.

 

Cat was clogged in the up-pipe as you guys mentioned. EGTS was gone which I suspect may have been received by the turbo as there was some noticeable play in the turbine shaft.

 

I've cut the cat out of the up-pipe and replaced the turbo core. We're doing better but still not 100%. I've received misfire codes but only for cylinder 1. I can run it all the way up to 6k just fine, shift and run it up again without issues though eventually I receive the misfire code but so far always on cylinder 1.

 

I'm not gonna throw more money at it just yet though I am gonna try a set of new replacement plugs I got free from a friend to see if maybe cylinder 1's is fouled as well as replace the others since I have an entire set.

 

A question I now have is, knowing that the Up-pipe cat was clogged, what is the likelihood that the cat within the crossover pipe before the up-pipe is also clogged/ in need of replacement?

 

I don't think I can cut the cat out of this crossover pipe as there isn't a straight shot through either end to it so I'd be looking to replace if required.

 

Thank you everyone who has helped thus far. Eventually it is going to make it back on the road hopefully before classes start up again.

[relative4]

There is no cat in the crossover pipe. The UP is the only cat before the turbo.

IMO, you should really pull the pan to assess the damage.

 

#YNANSB

[Max Capacity]

Make sure those free plugs are the right ones, gaped to .028"