Engline light + sputter + hissing + irregular idle -HELP!!

[czechT698]

Hello everyone,

Today I had the most unfortunate thing happen to me. Until now my car never had any difficulties. On the highway I gave it some gas in 5th gear, about 140kmh, when sudenly a car popped up in my lane so without depressing the clutch I floored the brake going down to about 100kmh (noticable deacceleration but nothing hardcore). After I floored it again, the yellow outline of an engine came up solid on the dash (dont know when exactly). There was more shaking then ussual and a loss of power. I immidiately pulled over to a gas station and popped the hood. The symptoms:

- irregular idle
- slight rattle coming from intake/DISA combine with loud (!!) HISSING (like an air leak - sounded like a pissed off snake)
- sputtering (misfire?)
- knocking (like backfire) in the exhaust

I left the car off for a while and then started again, the symptoms were still there, however the engine light was not present anymore.I decided to finish my short journey in 2000rpms in 5th gear and take it ASAP to BMW but the strange thing is, that when I stopped at a red light, the engine was running excellent again, no problems or these symptoms anymore... The car ran OK again. Will visit BMW tommorow.

Anyone have an idea of what the hell just happened with my car? - DISA? Coils? Vaccum leak on intake??
PLS HELP

[czechT698]

oh and its a 2003, 2.5i, with 142 000 on the clock

[czechT698]

[paddy wright]

could be a faulty coil pack

[MR_ZEE]

Not sure about the hissing, but rest of the symptoms sound like faulty ignition coil.

Happened to me a few weeks after I bought my Z4 - my friendly mechanic diagnosed it was running on 5 cylinders and told me to pop to BMW to get a replacement part (which he fitted for me in 2 minutes).

Hope this helps.

[czechT698]

I hope it is the coild pack then... the disa was rattling awfully and the hissing may have been caused by the lean misfire mode I hope everything turns out ok

[czechT698]

while I am at it Ill also tell him to throw a new disa... coudl it be anything besides the coils? I heard that a fautly camshaft position sensor can wereck havoc

[Smokin]

'03 2.5s had a problem with the coils. My 325Ci had one fail and it's scary, but easily fixed. Ran like a champ when they were replaced. I'd do that first before I jumped on the DISA.

[czechT698]

OK Ill let them diagnose it and hopefully it will be the coils.

What amazes me is the most is that the engine fealt like its totalled judging by the sound. After doing about 20 slow kilometers it was better, and after arriving home it was running like new again... Is that a symptom of the coils going bad? I think that I have the 03 OEM Bremi crap ones. Hope that a set of fresh Bosch can fix this.

Thnx for the help Smokin, !!!

[Shipkiller]

I find it strange that it started just when you had to do a braking maneuver.

IF, it is a COP (Coil on Plug), then the problem will return at a later date. Also, since the engine was bucking a lot (my interpretation of your description), was the CEL on steady or blinking???

An intermittent misfire will light the CEL steadily, but a real hard core misfire, ie. a bucking engine, the CEL will blink. Also, an misfire will be stored in the DME for six drive cycles and then cleared if it does not return.

Don't just jump to the conclusion that it is a bad COP.
BUT, if you know you have the Bremi COP's, then BMW has a recall/SIB on this issue and they should replace them for free.. but don't bank on it...

I don't think your DISA would cause this issue unless you sucked the pin into the engine. Since the problem went away, I don't think that happened either. If your DISA is noisy, then replace it.... You can tell if the DISA going bad by disconnecting the electrical cable to the DISA while the engine is running. If the noise goes away, that's your culprit for THAT issue... Remember, the DISA only deactivates (rotates the butterfly valve to the open position) at approx. 4100 RPM and above. Under 3700 RPM, it just sits there, closed. I am going to make an assumption that at 140kph, your engine RPM was around 3400-3600 RPM. Since your engine RPM was not at the deactivation point, the valve was closed anyway so HOW did it cause a 'lean condition'?

Camshaft position sensor. You may be actually talking about the Crankshaft Position sensor. I am not going to get into that here.

I have just addressed all the wild ass guess's that you have already read.

Now, let me make a wild half-ass educated guess..... Let's go back to the initial conditions. Hard braking... COULD, just a thought, you possibly have a little water in the fuel tank????? and that small amount of water was moved to fuel pump pickup because of the braking and it took just a little bit of time for the engine to pass that crap out?? Not sure, certainly plausible. Don't know....

There really is NOT ENOUGH information to make a diagnosis.... really there isn't. DON'T start throwing parts at the problem because the engine had one hiccup...

Take your car to BMW and have them hook it up to the computer and read the stored DME error codes. There MAY not be any. This could have been a fluke and you will never know what happened...

OR

The codes stored will point to a problem and you can get it resolved with minimal $$$$

[czechT698]

OK, since the problem went away the dealer and I have decided to let it drop with the case that if it comes back I would come drop it in for diagnostic.

Everything was fine until yesterday, when I had the same thing happen to me again - was tailgating an Audi TT uphil for about a minute in second gear and 5000rpm. After I stopped at a red light I had the same issue going on as before Sorry for the quality bud it was my unique chance. I restarted the car a few times and everything went back to normal - WTF??? Will visit the dealer, but i wont have time to do that for the next 174 days. In the meantime - anyone have an idea of what the hell is going on? Shipkiller?

[czechT698]

sorry 14 days

[Shipkiller]

sorry, at work and cannot get to the video. I will look at it tonight.

[EdButler]

This sounds EXACTLY like what happened to my old VX220, but with that, the throttle was totally unresponsive untill you very quickly switched the ignition off/on again... Basically it had an air leak in the inlet manifold/throttlebody connection...

When coming to a junction youd drop the clutch and like yours the revs would drop abnormally low. At this point youd here a *click* as the throttle plate slammed shut (this is because the MAP-MAnifold Pressure sensor is reading the wrong vacuum pressure due to the leak as unmetered air is now rushing into the inlet). At this point however the throttle had jammed on the VX, throwing an eml, however it still seems responsive on yours.

What is essentially happening then, is that the engine is being choked of air and the HISSING you can hear is the engine sucking air past a closed throttle as its gasping to stay running. The ECU however 'thinks' that the throttle is in the correct position, as the manifold pressure all checks out ok.

Have a search for 'Vacuum Leak' on google and there are many methods to track them down... Good luck!!

[Shipkiller]

Good description.

I would think that if this is the case, if the rip/opening in the intake will be on the intake boot, and the rip will be rather large. I had a ripped intake boot on the roadster. No drive-ability issues but a constant whistling/hissing from the tear in the rubber.

IF you do have an intake leak, it will unless it is audibly noticeable (as EdButler says), then it will take some time to track down.

Just thought of something. Just for giggles, check the rubber intake boot as it fits over the throttle body and make sure it is tight and not leaking. Since the bottom is hidden, the boot could have slipped off the lower lip of the throttle body. This would introduce a LARGE vacuum leak. These are the obvious things to check. Do a really good visual inspection and use your hands to feel around for anything that does not feel right.