throttle body actuator problem problem HELP! (SOLVED!)

[AriuSen]

So, my car on high rpm, around 7k rpm goes blap blap blap and I lose power.....and then a check engine light. plugged the OBD and it says throttle body actuator issue.

This happens once at every track day, but this last track day happened like 4 times....i just slow down a little and then problem goes away...and then blap blap blap after a while.

any guess???

I wish its not the actuator, because I heard they cost around 700???

any alternative you guys know of?

[chickdr]

Are you asking about an Z4M with an S54, or an E92 M3?

[AriuSen]

Originally Posted by chickdr

Are you asking about an Z4M with an S54, or an E92 M3?

z4m coupe. sorry

[Finnegan]

How electronically handy are you? With a multimeter and a YouTube video you can run a full diagnostic.

[AriuSen]

Originally Posted by Finnegan

How electronically handy are you? With a multimeter and a YouTube video you can run a full diagnostic.

[AriuSen]

LOLLLL bad edit....from a z4m my car turned into a formula 1 car lolol...just skip to the end where the worse blap happens

[Finnegan]

Originally Posted by AriuSen

LOLLLL bad edit....from a z4m my car turned into a formula 1 car lolol...just skip to the end where the worse blap happens

Well, it sure sounds good. From what I've looked at and read (fortunately no first hard experience) that's what happens with a failing actuator. The throttle bodies are just closing (default position) as the motor fails.

It could throttle position sensor too--but if you pulled the actual actuator code that's unlikely.

I think you may be stuck replacing it. One thing is for sure, it's not going to get better, and probably will get worse.

[AriuSen]

Originally Posted by Finnegan

Well, it sure sounds good. From what I've looked at and read (fortunately no first hard experience) that's what happens with a failing actuator. The throttle bodies are just closing (default position) as the motor fails.

It could throttle position sensor too--but if you pulled the actual actuator code that's unlikely.

I think you may be stuck replacing it. One thing is for sure, it's not going to get better, and probably will get worse.

I've been told of the position of the sensor issue.
I will try that first as my friend said it solved his problem... hope is just that! thank you!

[Vanne]

any Resolve Alex?

[AriuSen]

Originally Posted by Vanne

any Resolve Alex?

Lol....I've been so lazy these days to go to the track and test.
But I did a nice Canyon run this weekend and I didn't get any problem so far..but can't rly tell til I hit the track again...my next one is on 28th at bimmerfest

[AriuSen]

Originally Posted by Vanne

any Resolve Alex?

so lets see if anyone can solve this great mystery!!!

for last track day I changed a lot of sensors and I would guess problem would be solved.

I go to the track and first session in fifth gear....doing same problem, but this time not even popping, but losing power...it happened for 4 laps after 2 laps running well.....so I get annoyed and then next session, I leave my heater on max and voila! no more issues for the rest of the day????

could it be related to overheat then????

my ECU rly doesnt wanna tell me the specific problem!

[AriuSen]

Finnegan Vanne solved the problem!!!!!!!!!!
I thought was something mechanical, and i changed, alternator, spark plugs, coil pack, sensors, etc etc and the problem wouldnt go away!!! I was getting so pissed, and I quit track for a while because it was getting worse and worse to a point that I couldnt do 1 clean lap without losing power.
The problem?? BATTERY!...for some reason the battery wasnt carrying full voltage all the way to the front...I dont exactly remember the numbers, but the rear voltage was higher than the front....so my friend was telling me that as I go higher on rpm, the car requires more voltage.....therefore, without full voltage, my car would cut power....and it was getting worse and worse every track day, cuz the battery was getting weaker and weaker.....I replaced the positive cables and voila! full voltage and no more power loss.
Now I can be biased....this last saturday my friend with e46, was telling me that he couldnt catch me anymore on straight line, like he used to before....maybe now I have more power? lol

[angelr]

So did you change the battery or the cables? If it was cables, which ones?

[AriuSen]

Originally Posted by angelr

So did you change the battery or the cables? If it was cables, which ones?

Changed the long positive cable that goes all the way to the front.
Somehow the old cable wasnt carrying all the voltage

battery is the same....didnt have to replace it.

[angelr]

How much did that cable cost you? I've been chasing a similar issue for ages with no luck. Mine is just a slight drop in tq in the upper rpm range but I can feel it every time I run through that range.

[StickMon]

I would suggest carefully checking the connections at each end first.
I can't think of a reasonable failure mode in the middle of the cable.

[AriuSen]

Originally Posted by angelr

How much did that cable cost you? I've been chasing a similar issue for ages with no luck. Mine is just a slight drop in tq in the upper rpm range but I can feel it every time I run through that range.

costed about 100.
What I would do in your case is check the voltage in your trunk and then check the voltage under the hood. both must be the same. I beleive mine was 14 rear and 12 front.

If the front is lower, than I would see if both ends are well connected . If that doesnt solve, then replace cable like i did.

[AriuSen]

Originally Posted by StickMon

I would suggest carefully checking the connections at each end first.
I can't think of a reasonable failure mode in the middle of the cable.

Yea, we carefully checked everywhere...maybe 1 out of 50 wires got cut? no idea too...im just happy with my fix.

[Finnegan]

Originally Posted by AriuSen

Yea, we carefully checked everywhere...maybe 1 out of 50 wires got cut? no idea too...im just happy with my fix.

Great news! I'm glad you nailed it down! This is a stripped/gutted track car right? Cage, etc.? Its possible it happened somewhere in that process.

That's a pretty cheap fix to correct a maddening problem. The test procedure is simple too.

I can't think of a failure mode that would apply as noted by Stickmon. I do seem to recall a "something" about battery cables in this car. (Edit: E90 M3 had that issue with positive cable. Not Z4.)

[AriuSen]

Originally Posted by Finnegan

Great news! I'm glad you nailed it down! This is a stripped/gutted track car right? Cage, etc.? Its possible it happened somewhere in that process.

That's a pretty cheap fix to correct a maddening problem. The test procedure is simple too.

I can't think of a failure mode that would apply as noted by Stickmon. I do seem to recall a "something" about battery cables in this car. (Edit: E90 M3 had that issue with positive cable. Not Z4.)

I believe so too. I think it was damaged when gutting the sound system. But yea. Such a easy fix and I spent so much money to get to this.