[MrRipfrog]

My 07 335i is a December 06 delivery and I have sporadically had trouble with engine hesitation/pinning/chugging. For example, yesterday I was doing my normal commute on the freeway traveling about 40ish and had the opportunity to make a lane change and give it some gas. I have the steptronic and when I accelerated, not flooring it, the rpm's come up and boost starts to kick in and that's when it happens. I get this "clug clug clug" sound as if almost the engine isn't getting enough fuel or air or something…? or maybe no, or lack of, spark to a plug? The car did not downshift as I didn’t give it that much throttle.

Now I am running the Procede 1.47 and remember when Shiv was tuning my car during the LA dyno day, he mentioned that he heard the car pinging and thought I had some crappy gas in the tank. I assured him that I used Chevron 91 at the time. He asked if I let the girl drive it in which I replied, NOOOO way! He ended up putting a few gallons of race gas in the tank and finishing the tune. I have since switched to Shell 91 but I still get these little spurts of what I can only explain as a "clug" or "chug" sound in succession of a few rpm’s and then it seems to go away. I remember Shiv also mentioning a spark plug replacement and that some people were having problems with a single plug? Plug #6 or something? Does this sound familiar?

When I took the car into BMW for service, I removed the Procede unit and don't recall experiencing the problem. Could the added boost/tune from the Procede be enhancing or bringing out the problem?

I would like to hear some thoughts and opinions if you think this is the fuel pump or maybe some other deeper problem? Maybe I will pull the Procede and see if I can get the car to mimic the same problem and then take her in.

Thanks

[e90AW335i]

Fuel pump maybe? ....:

[Jonmartin]

check for a boost leak.

[MrRipfrog]

Originally Posted by Jonmartin

check for a boost leak.

How would I go about checking for a boost leak?

[RRGOO7]

deff sounds like fuel pump

[cn555ic]

either the hfp or just plain old bad batch of gas...when i get a bad batch of gas my car acts up when starting just like a bad pump, but then i go to a station that that has a good history with me and fill up and the car starts up and runs fine again

[Dascamel]

Even some 91 from shell or chevron causes issues, try switching gas stations also. The car tuned with Procede really gets fussy about the gas. But after that, fuel pump and other issues.

[PresaMat]

This might be a little off the wall... but I noticed when it got close to time to change my oil my car started getting sluggish and would almost feel like it was bogging. Oil change and car is back to new.

[SPC LV]

I have had the same fucking problem.. It's really pissing me off now. A few months back my car was doing exactly what you are describing with the PROcede. I took the PROcede out and could not replicate the problem. I always used Shell 93 gas and decided to try something else like BP and Sunoco and my car stopped acting up. Lately it's back to its old ways of spuddering and hesitating. Bad gas?? Does anyone have good gas?? PROcede seems very sensitive to certain gas it seems. Is there more people experiencing this?

[beepbeep]

Originally Posted by SPC LV

I have had the same fucking problem.. It's really pissing me off now. A few months back my car was doing exactly what you are describing with the PROcede. I took the PROcede out and could not replicate the problem. I always used Shell 93 gas and decided to try something else like BP and Sunoco and my car stopped acting up. Lately it's back to its old ways of spuddering and hesitating. Bad gas?? Does anyone have good gas?? PROcede seems very sensitive to certain gas it seems. Is there more people experiencing this?

Yes. Steptronic, Shell 91, 5280 ft altititude, 1.47. Am going to try Permatex NOS octane booster when it gets here. And will try 2.0 when it gets here.

[2ABRUPT]

This problem could stem from several sources. The Mazdaspeeds have this same problem and they found it to be bad fuel mapping in the ECU and it was recalled.

Here are the possible causes:

1) Ignition (spark plugs not gapped properly, or spark wires).
2) Fuel (bad fuel causing knock).
3) ECU fuel maps not properly configured for low boost moderate throttle levels.
4) An overly rich condition where the ECU is dumping too much fuel.
5) MAF sensor not computing the proper Airflow for the ECU (which would cause #4).
6) Knock.

What is is NOT:

It is NOT the fuel pump.
It is NOT a boost leak (otherwise you'd get low boost pressure).

Good Luck guys!

-M

[catdog]

Originally Posted by MrRipfrog

My 07 335i is a December 06 delivery and I have sporadically had trouble with engine hesitation/pinning/chugging. For example, yesterday I was doing my normal commute on the freeway traveling about 40ish and had the opportunity to make a lane change and give it some gas. I have the steptronic and when I accelerated, not flooring it, the rpm's come up and boost starts to kick in and that's when it happens. I get this "clug clug clug" sound as if almost the engine isn't getting enough fuel or air or something…? or maybe no, or lack of, spark to a plug? The car did not downshift as I didn’t give it that much throttle.

Now I am running the Procede 1.47 and remember when Shiv was tuning my car during the LA dyno day, he mentioned that he heard the car pinging and thought I had some crappy gas in the tank. I assured him that I used Chevron 91 at the time. He asked if I let the girl drive it in which I replied, NOOOO way! He ended up putting a few gallons of race gas in the tank and finishing the tune. I have since switched to Shell 91 but I still get these little spurts of what I can only explain as a "clug" or "chug" sound in succession of a few rpm’s and then it seems to go away. I remember Shiv also mentioning a spark plug replacement and that some people were having problems with a single plug? Plug #6 or something? Does this sound familiar?

When I took the car into BMW for service, I removed the Procede unit and don't recall experiencing the problem. Could the added boost/tune from the Procede be enhancing or bringing out the problem?

I would like to hear some thoughts and opinions if you think this is the fuel pump or maybe some other deeper problem? Maybe I will pull the Procede and see if I can get the car to mimic the same problem and then take her in.

Thanks

Had the same issue with Shell Vpower 93 which had been my favorite fuel; switched to Mobil 93 and has resolved that same problem. try a different fuel company...

[MrRipfrog]

Thanks for all the input everyone. I think the easiest course of action is firstly to burn off this tank and try another gas station. I was under the impression that Shell was good. Too bad only 91 here in smoke filled CA. (By the way, we CA folk should remember to clean or change our air filters when the fires are finally taken care of. I had a layer of ash all over my car today leaving work.)

If that does nothing, then I will go fill my tank up with 5 gallons of race fuel like Shiv did when tuning it.

It is also almost time to get an oil change, so that will be step 3.

If new gas, race gas and an oil change don't do anything, then I will remove the Procede and see if I can get some kind of similar symptoms. If so, in she goes to the dealership. If not, then I hope V2 will help to alleviate this persistent problem. It's really more of an annoyance than anything.

Funny thing is, the car seems to run strong for the most part. It's only when cruising at low rpm's and then giving gas gradually. While the rpm's start to rise, turbo's kick in and that's when it hits...

I will post my findings and maybe we can pinpoint if these cars on the Procede are just overly sensitive to shitty gas. Hope not.

Good luck to those with the same problem...

[Dascamel]

LBT map might also help...

[RiXst3r]

You could have the dealer reset all your adaptations and long term trims.

[gobo335i]

Is the computer cutting in and cutting you off? My car w/PROcede will trip the control when I'm on the throttle hard, especially over bumps. I know it sounds stupid, but it got me the first few times until i saw the yellow flash on the dash.

[catdog]

Originally Posted by MrRipfrog

Funny thing is, the car seems to run strong for the most part. It's only when cruising at low rpm's and then giving gas gradually. While the rpm's start to rise, turbo's kick in and that's when it hits...

EXACTLY what my car did until i switched from Shell to Mobil, and only started after the jbs2 had been in there for > 2 weeks. Now completely gone...car runs perfect and very very strong in cooler weather, it's scary i think it needs suspension and brake ugrades for this kind of performance.

Honestly, had the same exact issue: try different gas stations and companies, and be patient.