Poor Engine Performance

[NorCal-Dimitri]

My car has a bad case of the buckings and poor engine performance. 0-60 seems to take me about 8 seconds. The loss of power seems to be throughout all of the rpms. The hesitation in the car's revs are bad enough that I have to put the gas pedal all the way down to do a 1k rpm rev match. I'll try to get an acceleration and rev video on here.

I've read around and I think I'm going to go ahead and replace the fuel filter and vanos seals. If that doesn't help the bucking and hesitation I'll go ahead and clean and crimp the pins in the exhaust vanos solenoid (http://forum.e46fanatics.com/showthread.php?t=856781)

I don't think I have MAF issues, as it was replaced not too long ago.

What's the best way to diagnose poor O2 sensors?

Please post if you have any additional thoughts or ideas that could help me fix these issues.

[derbo]

Do you have a check engine light?

[NorCal-Dimitri]

Do you have a check engine light?

I had one turn on yesterday, but it disappeared on my drive home from Sacramento. I've been having these symptoms for a while it seems with no engine lights.

[gmurphy]

Try running some Techron too

[NorCal-Dimitri]

Try running some Techron too

Is there a brand that's best? I've actually never fueled up with anything other than Chevron 91.

[NorCal-Dimitri]

What about seafoam? I've heard good and bad about it.

[derbo]

What about seafoam? I've heard good and bad about it.

Try not to jump into a solution blindly. You will end up replacing more parts than necessary to fix it.

Since you saw a check engine light once, the car stored some faults. If you can, find someone with diagnostic software to pull the codes for you. A shop, someone near by or you buy the cables and do it yourself.

Once you get the codes, you will have a better idea where to look to resolving your issue. As you said there are alot of parts related to the stuttering.

How old is the fuel filter, spark plugs?

sent from Moto X Dev Edition

[gmurphy]

Is there a brand that's best? I've actually never fueled up with anything other than Chevron 91.

That has techron in it actually but I guess a concentrated bottle could help. It's worth a shot.

[brettbimmer]

Try not to jump into a solution blindly. You will end up replacing more parts than necessary to fix it.

Since you saw a check engine light once, the car stored some faults. If you can, find someone with diagnostic software to pull the codes for you. A shop, someone near by or you buy the cables and do it yourself.

Once you get the codes, you will have a better idea where to look to resolving your issue. As you said there are alot of parts related to the stuttering.

How old is the fuel filter, spark plugs?

sent from Moto X Dev Edition

Derek has a logical approach here which is very smart, so you aren't arbitrarily throwing parts at the car. If it has been happening over a period of time, then it sounds like possibly a fuel starvation issue and I would suspect the fuel filter too, depending on how long its been in service, or if by chance you picked up a bad tank of fuel at a new station which is thus clogging the filter.

[cakM3]

How many miles do you have on your car Dimitri?

[ryankokesh]

Since you saw a check engine light once, the car stored some faults. If you can, find someone with diagnostic software to pull the codes for you. A shop, someone near by or you buy the cables and do it yourself.

That.

[NorCal-Dimitri]

Try not to jump into a solution blindly. You will end up replacing more parts than necessary to fix it.

Since you saw a check engine light once, the car stored some faults. If you can, find someone with diagnostic software to pull the codes for you. A shop, someone near by or you buy the cables and do it yourself.

Once you get the codes, you will have a better idea where to look to resolving your issue. As you said there are alot of parts related to the stuttering.

How old is the fuel filter, spark plugs?

sent from Moto X Dev Edition

I have a couple of my friends nearby have the necessary equipment. I'll see if I can get to them today. I'm not near my maintenance records right now, so I'll have to get back to you on that.


Derek has a logical approach here which is very smart, so you aren't arbitrarily throwing parts at the car. If it has been happening over a period of time, then it sounds like possibly a fuel starvation issue and I would suspect the fuel filter too, depending on how long its been in service, or if by chance you picked up a bad tank of fuel at a new station which is thus clogging the filter.

Would a clog in the fuel filter also kill my gas milage?


How many miles do you have on your car Dimitri?

It's at 136k. I see 330s with 180-200k pulling much harder than mine.

[az3579]

Just so you know, having to floor it very quickly to rev match is normal. The drive by wire system in our cars SUCKS.

[danewilson77]

Could be clogged cat as well.

[NorCal-Dimitri]

Just so you know, having to floor it very quickly to rev match is normal. The drive by wire system in our cars SUCKS.

Is that common to zhps or all facelift e46s?


Could be clogged cat as well.

Hmm, is there a way to specifically diagnose that?

[ZHPESQ]

+1 Cats
Just went through the same thing.

[QC_ZHP]

Is that common to zhps or all facelift e46s?



Hmm, is there a way to specifically diagnose that?

Buy headers. Install Headers. :P

[NorCal-Dimitri]

Buy headers. Install Headers. :P

BRILLIANT. :mwah

[Captain Hindsight]

Sprint Booster will help with the drive by wire lag. One of the best mods I've done. Its a little module that plugs in to the back of the gas pedal and has 3 modes, stock, sport, or race. I leave mine set on sport most of the time. Makes rev matching soooo much easier.

[Karl Lazlo]

The DBW system notwithstanding...

The symptom that you articulated is very similar to the symptoms when my DISA went (at about the same age, as well).

Botond, if you need to learn how to double clutch with a throttle "blip," hit me up, we can go for a ride and I can show you... ;-)

[Avetiso]

Overall, just catch up on maintenance, man. Start with VANOS, then DISA, update your DME, fuel injector cleaner, new air filter, new pre cat O2 sensors... All of those can damage performance and if you haven't taken care of it.

[WOLFN8TR]

Overall, just catch up on maintenance, man. Start with VANOS, then DISA, update your DME, fuel injector cleaner, new air filter, new pre cat O2 sensors... All of those can damage performance and if you haven't taken care of it.

This! ^^

But I would do the fuel filter first. How many miles since it was changed? Run some fuel injector cleaner. Then pull the DISA and check it beings that is very easy to do. What about the fuel pump?

Just incase you need it. DISA for Sale on the Mafia.

http://www.zhpmafia.com/forums/showthread.php?13608-FS-Used-BMW-E46-330i-M54-3.0L-DISA-Valve-11617544805

[cakM3]

It's at 136k. I see 330s with 180-200k pulling much harder than mine.

You're at 136k....you might want to consider a fuel pump issue? I was at 148k on my ///M when the fuel pump gave out.

[az3579]

Is that common to zhps or all facelift e46s?


All Non-M E46's with drive-by-wire...
I haven't driven an E46 M3 very often, only a select few times and in that car, rev-matching isn't nearly as much of a problem, especially with sport mode on.



Botond, if you need to learn how to double clutch with a throttle "blip," hit me up, we can go for a ride and I can show you... ;-)

Funny guy...

[brettbimmer]

Would a clog in the fuel filter also kill my gas mileage?


By itself, I doubt it. That said, if you haven't done the general items noted like spark plugs, fluids, etc., then these could be contributing to the poor mileage. Likewise if you have to floor the throttle often to make her move, then that probably isn't helping mileage either.

[CarbonZHP]

Check DISA bearings. Pull oil filler cap when running and check the vacuum. Fuel pump could be but then youd be running lean. Hence code.

[NorCal-Dimitri]

Thanks for all the help, guys. I'm getting a code scanner today.

Just looked through the maintenance records. They say that the fuel filter and pump were both replaced about 41k miles ago. I guess it's fairly safe to say that it's not the pump. How often do you guys change your fuel filters?

[stephenkirsh]

You're at 136k....you might want to consider a fuel pump issue? I was at 148k on my ///M when the fuel pump gave out.

I came here to add fuel pump to the list. That is a common source for this issue on bimmerforums

[stephenkirsh]

All Non-M E46's with drive-by-wire...


Nope. M52 engines (323 and 328) had cable actuated throttles.

[gmurphy]

Nope. M52 engines (323 and 328) had cable actuated throttles.

I think he was just saying it's common in all Non M E46s with drive by wire. As opposed to saying all E46s have it.

[stephenkirsh]

Well that's embarrassing. My bad :(

[az3579]

Nope. M52 engines (323 and 328) had cable actuated throttles.


I think he was just saying it's common in all Non M E46s with drive by wire. As opposed to saying all E46s have it.

^ Yes, this.

[NorCal-Dimitri]

^ Yes, this.

That's interesting, but it confirms that my car does have hesitation issues compared to other E46's. I drove a friend's 2002 330xi and the throttle felt completely different. Rev-matching was much easier.

I was at a friends house and used his peake code scanner since mine hadn't arrived from amazon yet. It told me that I needed to replace a crankshaft sensor (?) and that the pre-cat O2 sensors weren't good. Today I received my Innova code scanner and it produced P2098, the post cat fuel is too lean.

[alexandre]

O2 sensors are generally a 100k maintenance item so you're overdue. Bosch 17215 & 17216. ~$100 each. When I replaced mine it made a huge difference.

Clean the MAF, ICV and throttle body as well.

[ELCID86]

O2 sensors are generally a 100k maintenance item so you're overdue. Bosch 17215 & 17216. ~$100 each. When I replaced mine it made a huge difference.

Clean the MAF, ICV and throttle body as well.

I need to do this! Only two sensors?


Thumbs, iPhone, Tapatalk.

[TWong1200]

So have you figured this out yet?

[Johal E32]

I need to do this! Only two sensors?


Thumbs, iPhone, Tapatalk.
Car has 4 sensors. Most people just replace pre cats. So 2 pre cat, 2 post cat

[mbeckel]

Car has 4 sensors. Most people just replace pre cats. So 2 pre cat, 2 post cat
Typically the postcat sensors aren't dirty like the precat. The life of them is rather long.

[ELCID86]

^thanks guys. These pre's are in hand and next on my list todo.

Fuel pump replacement has helped a ton though.

Thumbs, iPhone, Tapatalk.

[mbeckel]

^thanks guys. These pre's are in hand and next on my list todo.

Fuel pump replacement has helped a ton though.

Thumbs, iPhone, Tapatalk.
Get some PB blast, soak it for a good 30 min to 1 hour before trying removal. A propane blow torch could be handy as well. Tools needed as well, O2 sensor socket for either 3/8 or 1/2 drive

[ELCID86]

Thanks Matt. I have the PB and tool. No heat though :-(


Thumbs, iPhone, Tapatalk.

[danewilson77]

Get some PB blast, soak it for a good 30 min to 1 hour before trying removal. A propane blow torch could be handy as well. Tools needed as well, O2 sensor socket for either 3/8 or 1/2 drive
Yes. All of that.

The friendliest forum on the planet!

[mbeckel]

Yes. All of that.

The friendliest forum on the planet!
Learn from my mistake! :thumbsup

[danewilson77]

Learn from my mistake! :thumbsup
And mine.

The friendliest forum on the planet!

[Avetiso]

My precats came right out lol. Pretty easy.

[ELCID86]

My precats came right out lol. Pretty easy.

I've got 182k on his car and I'm not hopeful...


Thumbs, iPhone, Tapatalk.

[Avetiso]

I've got 182k on his car and I'm not hopeful...


Thumbs, iPhone, Tapatalk.
Haha, well my car was from the Ohio and was plenty salty, so if mine was fine at low mileage there certainly is a possibility yours will be easy.

[Johal E32]

Did post and precat at 216k. Super easy.

[NorCal-Dimitri]

So have you figured this out yet?

Preparing for college has taken priority unfortunately...
I have yet to do anything except scan codes.

[stephenkirsh]

Pfft, you can do college at any time!

[NorCal-Dimitri]

Here's a first world problem for ya:

I can't figure out why my bmw won't drive fast and since I'm getting scholarships I can't postpone college...

[danewilson77]

Lol....

The friendliest forum on the planet!

[CarbonZHP]

Lol....

The friendliest forum on the planet!

+1

Your oil level is good right? After adding oil my car felt significantly better, especially planting the throttle with low revs in 4th. Exhaust also got louder...idk

[NorCal-Dimitri]

Yeah, my oil level is spot on. The car does seem to eat oil, but my dad's e46 is just as bad.

[NorCal-Dimitri]

Dane's comment about a possible clogged cat has been floating around in the back of my mind. I noticed after polishing and cleaning my exhaust that one pipe fouls up much more quickly than the other. Could this point towards a clogged cat or incorrect fuel mixture? Could it be that the PO put a single tip exhaust on the car to hide this?

[alexandre]

Dane's comment about a possible clogged cat has been floating around in the back of my mind. I noticed after polishing and cleaning my exhaust that one pipe fouls up much more quickly than the other. Could this point towards a clogged cat or incorrect fuel mixture? Could it be that the PO put a single tip exhaust on the car to hide this?

I'm on my original cats at 235k and my pipes foul up at the same rate, and my car runs rich for long periods of time due to the weather up here. 136k seems premature for a cat failure, most of us super-high mileage guys start being weary at 200+.

Did you run the codes ? Inspect O2 sensors, DISA, etc. ?

Also if you're still on original VANOS definitely address this first. The OEM seals are gone at like 60k.

[NorCal-Dimitri]

I'm on my original cats at 235k and my pipes foul up at the same rate, and my car runs rich for long periods of time due to the weather up here. 136k seems premature for a cat failure, most of us super-high mileage guys start being weary at 200+.

Did you run the codes ? Inspect O2 sensors, DISA, etc. ?

Also if you're still on original VANOS definitely address this first. The OEM seals are gone at like 60k.

I haven't had the chance to, unfortunately. Would an O2 sensor failure cause one pipe to foul up faster than the other?

[alexandre]

Doubt it. I don't think it's a very reliable indicator of cat condition lol. The pre and post cat O2's function is to monitor cat efficiency. They will store codes if a cat is failing.

[stephenkirsh]

I thought the exhaust gets combined in the muffler? So it doesn't exit as dual pipes, functionally.

[NorCal-Dimitri]

I have a tse3, which doesn't combine in the muffler, or so it appears.

[Johal E32]

This may have been discussed, but how old is your CCV? A bad CCV can cause blow by - which can explain oil consumption

[NorCal-Dimitri]

This may have been discussed, but how old is your CCV? A bad CCV can cause blow by - which can explain oil consumption

Never considered that. I'll check it out. Thanks.

[Johal E32]

Never considered that. I'll check it out. Thanks.

Yeah check this for sure, if it's original you should replace it with a new unit and all the associated hoses. It's good preventative maintenance as they all fail at some point.

[johnrando]

Yup, changing out my CCV definitely improved how Ness runs.

Sent from mobile