Jump to content
Jushed

535d power loss after 3rpm

Recommended Posts

Also, I've taken off the manifold before I went for remap and cleaned out intake, maf sensor boost sensor charge pipes  replaced fuel filter put k and n filter and fresh Castrol. When I took off the manifold that converter there's looked all right and the hoses looked alright and that was about 2 months ago then I put everuthing back in

Share this post


Link to post
Share on other sites
14 minutes ago, Jushed said:

Not all the time but after clearing off the code and shutting down the engine and turning the ignition on and scan it and BOOM!  (like Russian hacker on youtube) the code is there. I spoke a bmw specialist who sorted me out in the past when other mechanics couldn't, I told him the symptoms and told him some figures  he's saying the turbo is over boosting, he said the guy that mapped it he put too much boost on the turbo as a result the sensor detects over boost and cuts down power and hence the fault is intermittent, I've told him after that, the actual boost pressure around 40hpa higher than the set point boost pressure then he said there you go the turbo is over boosting, that's why the oem sensor is detecting too much boost and throwing the code as intermittent, ill be taking it on dyno soon to see how much bhp I lost and how much bhp it goes down to especially the time when it's screaming up the rev with little boost. What he said does kind of make sense he said he'll talk one of his guy that does them things to adjust the boost and things but that means hell put down the overall bhp. When I speak my remapper he tells me change all the vac hoses and pressure converters, he saying the pressure converters or vac hose are bad that's why boost loss 

 

Perhaps the fault isn't deleted. If the engine was still running when you cleared the code perhaps it came back whilst the engine was running. We need to know if the code comes back if cleared without the engine running and comes back before it's started again. If so it cannot be the vacuum system it has to be electrical.

 

The too much boost point raised by your mechanic is valid to a point. If you put too much boost on the map then when you're hammering the car if the boost goes over something like 2 bar the MAP sensor picks this up, throws an overboost error and the car goes into limp mode. But you were fine for a while and the fault has appeared so it can't be the map - that hasn't changed.

 

The mapper guy has a point. If it was OK and now it's not it must be a fault with the car.

 

If the fault only comes on when the engine is running then my money is on a vacuum issue. A hand vacuum pump can be got for about £12 on ebay. You can check the whole system without removing the intake manifold. Although really the intake manifold needs to come off but that only takes 20 mins.

 

Use the vacuum pump to check each feed off the main vacuum pipe holds a vacuum:

 

EGR

Engine Mounts + exhaust flap (on the same feed often)

Swirl flaps (still needs to be plugged)

Wastegate

Compressor bypass

 

Then check when you connect to the splitter these holes aren't blocked by disconnecting two of them and checking you can't pull a vacuum on either of them with another disconnected.

 

image.png.7af975bf576ce888e7549e7f0fa9da2a.png

 

 

Share this post


Link to post
Share on other sites

Thank you so much for this detailed response, i have just ordered a vaccum pump test kit, once I get it ill strip everything down and check all the vacuum hoses make sure they all hold vacuum the thing I'm going to do is replace every vacuum hose and converters if it doesn't solve it ill give up lool and I do remember the code comming on with ignition without engine start but I'm trying to see if it comes again, I'm clearing the code with ignition on and turn it off then give it while then turn the ignition on and rescan it, I've tried it lately I'm not getting the code to come on instantly, sometimes it would take few minutes of driving the car for the code to come, but  it definitely comes back on when I clear the code with the engine on and then check again no code then turn the ignition off and then ignition on and the code is there. So just just confirm, I should check every pipe for holding vacuum right. 

Share this post


Link to post
Share on other sites

You can check the vacuum system without running the engine. Basically every part should hold a vacuum once you've evacuated any reservoirs or actuators on that part of the circuit.

 

Actuators should move and return when you release the vacuum.

Share this post


Link to post
Share on other sites

Hey guys, remember I was saying the car drives fine for the first 10 15 minutes then it loses about 70 or 80 bhp but I was worried it may have lost the overall bhp which was 347.7 bhp on dyno, so I thought it to dyno again, and switched off the engine cleared off the code and re scanned it to make sure it's not there and then after 20 minutes engine off and went for 2 runs, first run 344bhp second run 346 bhp so I'm happy I haven't lost any overall bhp from 347 but I know after 10 or 15 minutes of driving the car, it goes into slight limp mode and power goes back to about 270 stock bhp, meanwhile I have ordered 2 pressure converters and vacuum hoses to replace but if the vacuum leak was the cause, wouldn't I lose the overall bhp weather in the first 10 minutes or after the 10 minutes off driving. Vacuum leak should have resulted in overall power loss but I haven't lost any overall bhp, only after 10 or 15 minutes that's when I lose the extra bhp.

Share this post


Link to post
Share on other sites

The other day I was testing out each vacuum hoses and converters by taking them off and drove it to see what difference they would make, and when I completely disconnected and drove the car, the result of boost loss was instant, when I disconnected them hoses and drove, either I won't have any boost from small turbo, or no boost from the big turbo when I disconnected the other hoses, and when I put them back, it was all good, the point I'm trying to make is, if the vacuum leak was the culprit, the power loss would be instant, and I would have lost some of my total bhp. But the issue I have come to is after driving the car for about 10 minutes it drops the power back to pretty much stock level it becomes sluggish. 

Share this post


Link to post
Share on other sites

I had a similar issue to this last night with my car would not revpast 3k was showing error for maf borrowed one of friends car tried again and issue had gone and power seems back to normal now maybe worth a look on yours?

Share this post


Link to post
Share on other sites

Fixed, I got a ecu remapper to adjust  some value which in turn deleted the fault codes of the ecu and all good again, at least so far all good. Thanks for the help guys appreciate it alot 

Share this post


Link to post
Share on other sites

Juts picked up on this post..! 

Glad to hear that you resolved the problem.

I've been running around in circles with this puzzle..

This is my approach to diagnosing, firstly my fault codes are 41AB Boost Pressure Sensor + 41ED Cyclic Authentication (2nd code is in Information history) INPA Software used to read faults. 

I've replaced all the vacuum hoses up to the Engine mount pressure converter, going beyond was too much work on the day i was working on car. I even replaced the vacuum supply manifold which now has its own supply to the Engine Mount P/C, i did notice the 4/way plastic junction feeding lights, engine mount and swirl flaps was bunged up with crap. I cleaned that it out and separated the feeds, I've replaced the Air temp sensor on the alloy air supply to intake pipe along with 2 MAP sensors. All seals from EGR to Turbo..

So a couple of things I've picked up using diagnostic software.

1.When looking at DDE status on INPA actual boost is higher than what it should be. (i was told the car was mapped when i bought it no proof to back up..)

2. When i clear the code and go for a drive the rev counter no longer jumps up and down erratically. ( i think this will be due to EGR being active , when a fault occurs in the DDE it stops the EGR and DPF regen) 

3. When i use DIS the report says there's a difference of around 5mbar between the MAP/MAF sensors, the lower reading being in the MAF sensor.

 

Now after some research i managed to pick up on a couple of threads using just the fault codes in Google search that some folk think its down to bad mapping. I dont have knowledge in this area but can imagine that some gains can be had through manipulation in the ECU. If this problem lies in the mapping then i will be in touch with MashedPotatoes  to arrange a visit. 

Thanks for your advice

Share this post


Link to post
Share on other sites

You can just imagine what I went through, I was running around like headless chicken and I've seen people on forums changed literally everything you can possibly imagine and still couldn't get rid of that code for boost pressure sensor. The only way I got it done was by a really good remapper, yes my actual boost pressure was more higher than set point boost pressure. If you are around London I can send you to that guy who sorted mine out, he adjusted the map as well also had Dyno and he gave me 2 runs it showed on Dyno my one pushing 350bhp and 711nm torque 

Share this post


Link to post
Share on other sites
21 hours ago, BigMuthaTrUKa said:

Juts picked up on this post..! 

Glad to hear that you resolved the problem.

I've been running around in circles with this puzzle..

This is my approach to diagnosing, firstly my fault codes are 41AB Boost Pressure Sensor + 41ED Cyclic Authentication (2nd code is in Information history) INPA Software used to read faults. 

I've replaced all the vacuum hoses up to the Engine mount pressure converter, going beyond was too much work on the day i was working on car. I even replaced the vacuum supply manifold which now has its own supply to the Engine Mount P/C, i did notice the 4/way plastic junction feeding lights, engine mount and swirl flaps was bunged up with crap. I cleaned that it out and separated the feeds, I've replaced the Air temp sensor on the alloy air supply to intake pipe along with 2 MAP sensors. All seals from EGR to Turbo..

So a couple of things I've picked up using diagnostic software.

1.When looking at DDE status on INPA actual boost is higher than what it should be. (i was told the car was mapped when i bought it no proof to back up..)

2. When i clear the code and go for a drive the rev counter no longer jumps up and down erratically. ( i think this will be due to EGR being active , when a fault occurs in the DDE it stops the EGR and DPF regen) 

3. When i use DIS the report says there's a difference of around 5mbar between the MAP/MAF sensors, the lower reading being in the MAF sensor.

 

Now after some research i managed to pick up on a couple of threads using just the fault codes in Google search that some folk think its down to bad mapping. I dont have knowledge in this area but can imagine that some gains can be had through manipulation in the ECU. If this problem lies in the mapping then i will be in touch with MashedPotatoes  to arrange a visit. 

Thanks for your advice

 

Are you saying you have a 41AB fault code that won't go away.

 

I have a theory on this.....

 

The error is being raised because the exhaust pressure is more than 80mbar different from the ambient pressure. The car does a basic check when the engine isn't running.

 

The  exhaust pressure sensor is right next the vacuum reservoir. It is connected via a rubber hose to a pipe on the catalytic converter. So perhaps it's this sensor that is faulty. It could be a blocked or broken pipe. You can get to the sensor and pipe just by removing the acoustic cover.

Share this post


Link to post
Share on other sites
2 hours ago, Jushed said:

You can just imagine what I went through, I was running around like headless chicken and I've seen people on forums changed literally everything you can possibly imagine and still couldn't get rid of that code for boost pressure sensor. The only way I got it done was by a really good remapper, yes my actual boost pressure was more higher than set point boost pressure. If you are around London I can send you to that guy who sorted mine out, he adjusted the map as well also had Dyno and he gave me 2 runs it showed on Dyno my one pushing 350bhp and 711nm torque 

Thanks for reply Jushed

I live up north in Merseyside pal but thanks for offering. Do you mind me asking what you were charged for the map alteration to sort your problem.

Share this post


Link to post
Share on other sites
2 hours ago, JasonH said:

 

Are you saying you have a 41AB fault code that won't go away.

 

I have a theory on this.....

 

The error is being raised because the exhaust pressure is more than 80mbar different from the ambient pressure. The car does a basic check when the engine isn't running.

 

The  exhaust pressure sensor is right next the vacuum reservoir. It is connected via a rubber hose to a pipe on the catalytic converter. So perhaps it's this sensor that is faulty. It could be a blocked or broken pipe. You can get to the sensor and pipe just by removing the acoustic cover.

Hello Jason 

Didn't know about this sensor and pressure pipe, i thought it was silencer flap controller.  Am i wrong about the there being a pressure sensor in the MAF as well, i am going from memory.. When i get home i will run DIS again and provide some screen shots. But yes when i scan the DDE for errors and clear them, i'll start the car straight away go for a run then switch off then back on followed by a scan. Scan throws up 41AB code every time.

Share this post


Link to post
Share on other sites

Sure it's presure convertor or something like that, I've had same issues and it kept blowing 1 of the yellow 20 amps, I also redid all hoses both sides, a leak in the anti shudder valve can cause issues make sure when you start the car the big wastegate compresses little 1 should be stiff by a 15 quid hand vaccum pump of amazon worth it's weight in cold, change the changeover valve for egr or swirl flap 1 switch the actuators over. 

Try all this things 1 at a time see if anything changes check the wires to the actuators ad well, I swapped all my vac hoses with silicone if you need a hand with routing let me know check the air box pipes got no splits in it as well mine had a big gash at the back you couldn't see made it rev and not pull top end

Edited by khanny

Share this post


Link to post
Share on other sites
11 hours ago, BigMuthaTrUKa said:

Hello Jason 

Didn't know about this sensor and pressure pipe, i thought it was silencer flap controller.  Am i wrong about the there being a pressure sensor in the MAF as well, i am going from memory.. When i get home i will run DIS again and provide some screen shots. But yes when i scan the DDE for errors and clear them, i'll start the car straight away go for a run then switch off then back on followed by a scan. Scan throws up 41AB code every time.

 

The MAF doesn't have a pressure sensor, it does include yet another temperature sensor through.

 

On your car:

 

There's a MAP sensor (Manifold Pressure Sensor) pushed into a grommet in the back of the intake manifold.

The DDE has an internal pressure sensor for ambient pressure.

There's the exhaust pressure sensor before the DPF.

 

There may be other pressure sensors - I can't remember.

 

That 41AB code has stumped most people for a long time but I recently saw something in the ISTA diagnostics that explained that the exhaust pressure sensor contributed to that specific code. That sensor has a foil wrapped rubber hose going down to the cat. I think the problem is that hose or sensor.

 

Share this post


Link to post
Share on other sites

It cost me about 200 pound, I've replaced other things as well nothing helped, I've replaced the pressure converters, vacc hoses, exhaust back pressure sensor, boost pressure sensor. Only solution was to delete the code from the ecu which is more cheaper than randomly replacing everything. You can see on forums some people went as far as changing the whole inlet manifold, turbo actuators, by pass valves and many more ball shrinking expensive parts and still couldn't get rid of the code. I would highly suggest you to go to a good remapper or ecu code remover and try to map that code out

Share this post


Link to post
Share on other sites
20 hours ago, khanny said:

Sure it's presure convertor or something like that, I've had same issues and it kept blowing 1 of the yellow 20 amps, I also redid all hoses both sides, a leak in the anti shudder valve can cause issues make sure when you start the car the big wastegate compresses little 1 should be stiff by a 15 quid hand vaccum pump of amazon worth it's weight in cold, change the changeover valve for egr or swirl flap 1 switch the actuators over. 

Try all this things 1 at a time see if anything changes check the wires to the actuators ad well, I swapped all my vac hoses with silicone if you need a hand with routing let me know check the air box pipes got no splits in it as well mine had a big gash at the back you couldn't see made it rev and not pull top end

Thanks for reply Khanny

I've just ordered a pump so in a couple of days i'll break out the tools. I'm ok with the plumbing JasonH sent me some comprehensive documents on the Turbo layout. Will check them fuses too..

Share this post


Link to post
Share on other sites
6 hours ago, Jushed said:

It cost me about 200 pound, I've replaced other things as well nothing helped, I've replaced the pressure converters, vacc hoses, exhaust back pressure sensor, boost pressure sensor. Only solution was to delete the code from the ecu which is more cheaper than randomly replacing everything. You can see on forums some people went as far as changing the whole inlet manifold, turbo actuators, by pass valves and many more ball shrinking expensive parts and still couldn't get rid of the code. I would highly suggest you to go to a good remapper or ecu code remover and try to map that code out

Thanks for reply Jushed

I hear your frustration, its had me under the bonnet on a regular basis.. just gonna have a look at the DPF system and check vacuum before i decide what move to make on my puzzle..

Edited by BigMuthaTrUKa

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×