[Mullerlicious]

Hi guys.

I have a 2007 320d with the m47 engine. 103k miles.

It's had an issue over the last 10 months whereby the car drives but it's very much down on power, lumpy starts, vague throttle response, occasional big cloud of smoke when it finally kicks in. Sometimes it takes 4 seconds to react to a throttle input. No lights on the dash.

So what have I done about this. The errors are always glow plugs, relay, and smooth running fault.

I've changed the plugs twice, and the relay twice. On both occasions it runs well for 2 days, and then it's back to running awful.

Has anyone had this issue ? I don't wish to sell the car but it's become quite annoying. I'm thinking maybe the power cable to the glow plug relay is the issue but haven't got the means to test it myself at the moment.

[Daviebrown]

Don’t be dragged down a blind alley by the glowplug fault, once running you can forget about the glowplugs, the smooth running fault needs further diagnosis, it could be caused by a number of things that won’t throw a light

[richard_tricky]

Smooth running control is normally injectors out of spec.

Might need refurbishment.

As for the 4 second hesitation. Im guessing thats possibly a seperate fault..

Can you post the codes here?

[Mullerlicious]

Thanks for the replies guys.

I have had my injectors tested and they're all running fine.

I also unplugged the MAF to see if that changed anything but it didn't.

I find it strange that on both occasions I had the relay and plugs changed, that it was fine for two days and then back to rough running.

I'll go double check the fault codes again.

[MrSweet1991]

Originally Posted by Mullerlicious

Thanks for the replies guys.

I have had my injectors tested and they're all running fine.

I also unplugged the MAF to see if that changed anything but it didn't.

I find it strange that on both occasions I had the relay and plugs changed, that it was fine for two days and then back to rough running.

I'll go double check the fault codes again.

Can you get actual vs expected results from INPA?

[nomiS330d]

I too can’t see why glow plugs make any difference to how the car runs and performs when it’s actually up and running. I don’t get fault codes on my 330d but in very cold weather it always takes twice the normal amount of cranking before it starts then smokes for a few seconds. After that it’s fine so either my glow plugs or the controller aren’t doing what they should be doing but once running it’s fine. What codes have you got at the moment?

[Mullerlicious]

Thanks guys.

MrSweet - I only have a Foxwell 200 code reader, so would need to get hold of the INPA software or someone who has it.

Nomis- I thought that with regards to the glow plugs, but I'm told they run at all times and not just the starting process. I'm getting all of these symptoms:

https://www.yourmechanic.com/article...ing-glow-plugs

Bizarrely, I cleared the fault codes yesterday and nothing has came back, so I actually have no codes right now. No lights on the dash.

The symptoms are exactly the same as before when I did have the plugs and relay errors.

I'll take a video tomorrow of it running, but it's basically rough start, rough idle, doesn't rev cleanly, occasional clouds of smoke and revs, misfires. I'd imagine the MAP would throw a code. I can't help but think it the GP relay, perhaps not getting the right power.

Thanks again appreciate it

[rasa bmw]

swirl flap and egr also need to be checked,these can have throttle response probs

[Mullerlicious]

Thanks for that Rasa.

I'm having slightly different symptoms now.

Rough start, wobbly idle, light throttle input won't rev past 2k RPM and white smoke appears.

If I floor it, it revs freely, if I'm light footed it hangs at 2k rpm and shows white smoke. No codes, no warning lights.

:

[Silver Streek]

Originally Posted by Mullerlicious

Thanks for that Rasa.

I'm having slightly different symptoms now.

Rough start, wobbly idle, light throttle input won't rev past 2k RPM and white smoke appears.

If I floor it, it revs freely, if I'm light footed it hangs at 2k rpm and shows white smoke. No codes, no warning lights.

:

Sounds like EGR issues to me. When you floor it the EGR is closed. On light throttle the EGR is active opening and closing. So when it plays up its more than often on light throttle. If its open too much it causes rough running with hesitation. Really worth looking at. If you have the M47 engine the easiest way to check is pull the vac pipe for the EGR and see how it runs. Also pull off the air pipe and see if the EGR is opening and closing properly before you pull off the vac pipe.

You say on full throttle it pulls but takes a while to kick in, sounds like the EGR is sticky and taking time to close. See how mucky it is by taking g off the air pipe.

[richard_tricky]

Please try and get the codes read and Come back here. It's very difficult to diagnose without them.

Right now it could be anything with those symptoms..

Egr, injectors, timing chain jump, swirl flaps etc etc.

If you have a cable there's free download to I pa and itsa-d on the bimmergeeks website.

Thanks

[Mullerlicious]

Thanks for taking the time to post guys, really appreciate it. As I say, no codes showing but I'll get on it tomorrow as I have a day off.

Cheers guys

[Mullerlicious]

Well had an explore today and the EGR doesn't even move under load. Will give it a bath and see if that is the culprit but I gather it certainly isn't helping.

[McPikie]

Originally Posted by Mullerlicious

Well had an explore today and the EGR doesn't even move under load. Will give it a bath and see if that is the culprit but I gather it certainly isn't helping.

I've got a spare inlet manifold here with the swirl flaps already blanked off if you want it for cheaps. May as well swap that out whilst messing with the EGR

[chrissyw]

I've got the same engine as you with a very similar issue.

Replaced the plugs and controller, which did improve things. I only noticed it in the winter at first, so thought it was the plugs.

If I leave it for a good few days and fire it up, it shakes for a few seconds and puffs out some blue smoke, then runs fine - any weather. I believe the plugs only activate when the temp is below 6 degrees?

INPA has confirmed injector 2 is really lazy and needs replacing. It returns to acceptable levels after about a minute of the car running. I've ran it on Millers EcoMax since around 100k. It's nearly on 180k now so I guess near the end of life for the injectors.


Mines deflapped, EGR deleted and mapped out.

My MAP sensor failed and the car just didn't boost at all. Struggled to get it up a hill in 3rd gear. Worth changing it if you get inlet manifold off.

[Mullerlicious]

Thanks McPickie, I'll keep that in mind.

My issues have been confusing because there's been more than one. EGR, glow plugs, and now I believe there is an injector leaking.

Will test soon and see what it says. I'll probably end up replacing the map too. Very annoying I hope it's all worth it lol. I know if I sell I'll end up losing money hence persevering.

[rasa bmw]

wait a minute,,,you have had it remapped ? why didnt you say,,could be a map prob.more worms

[Mullerlicious]

It's not mapped no, standard car. was just talking about the map sensor

[ozziewizzle]

Just a thought... Are you not burning too much oil? I once had a 320i which bad valve stem seals which meant instead of just burning fuel I was burning both leading to a sluggish car. How long is it between it burns a litre?

[Mullerlicious]

Originally Posted by ozziewizzle

Just a thought... Are you not burning too much oil? I once had a 320i which bad valve stem seals which meant instead of just burning fuel I was burning both leading to a sluggish car. How long is it between it burns a litre?

It doesn't use a drop of oil mate but thank you. I suspected that too at one point.

I'm confident the order or problems have been glow plugs and relay (fixed), egr blocked (cleaned), maf dirty (cleaned up) and finally leaky injector which I'm having tested.

I'm not overly experienced with diesels but there seems like symptoms cover a broad range of potential issues. I'll report back when it's fixed. Trouble is im looking at E90 330i's now I'm working from home

[richard_tricky]

Originally Posted by Mullerlicious

Thanks McPickie, I'll keep that in mind.

My issues have been confusing because there's been more than one. EGR, glow plugs, and now I believe there is an injector leaking.

Will test soon and see what it says. I'll probably end up replacing the map too. Very annoying I hope it's all worth it lol. I know if I sell I'll end up losing money hence persevering.

The smooth running fault code would probably be linked to a leaking injector.

Have a read up on the dde smooth running control on Google . On the m57 it works up until 1500 rpm then switches off.

If an injector is out of spec obviously the dde can't correct..

On my old e39 530d the car would shake at idle at around 1500 rpm there would be a little wobble then smooth out..