Low idle and stalls

[StuCollinsUK]

Hi guys, having some running/stalling issues and would like to get your thoughts (m52 1998).


Brief description of how the car has been behaving...revs pulling low when idling, can drive it but when coming to a stop the car stalls most of the time. Will fire back up again but will repeat this behaviour.

I unplugged the mass air flow sensor and the car ran immediately better, so by default thought it needed replacing.

Bought an aftermarket MAF and it was getting the mixture all wrong, presumed it was garbage - to rule it out swapped another MAF off my dads M52 2.8, but it went back to dropping revs and the stalling issue...


Plugged in to a computer and the following codes appear (MAF did not show when plugged back in and codes cleared):


217 - CAN: Timeout AGS/Electronic Transmission Control (EGS)

55 - O2 Sensor 2 Heater Before CAT

65 - Camshaft Position Sensor

52 - Exhaust Flap Solenoid Valves

202 - O2 Bank 1 Control Limit


Obviously would like to address all of these at some stage, but does anyone have any insight as to which is directly the culprit causing low pulling revs/stalling?

I’m guessing the reason it runs better without the MAF plugged in is the default programme the car is using also overrides the main culprit?!


Many thanks in advance!


Stu

 

[Richardrix]

I'd be going with Cam Shaft position sensor. That will cause the car to stall and stop randomly. May even stop the car being able to start.

 

[Brian4]

Also check the rubber hoses after the MAF to the throttle body especially around the bellows section and where the small vacuum pipes join as they perish here and allow air in after the MAF.

 

[t-tony]

Cam sensor first thing ,but, you have you cleared the codes and run it again to see what comes back. Some of those could well be historic codes where the issue was fixed but the fault codes not cleared.

Tony.

 

[colb]

Agree cam sensor to change first and clear all the codes to see what comes back. Check all rubber hoses for splits or holes replace any that are duff. You are correct unplugging the Maf will cause the car to run on default seetings. Never buy pattern parts especially Maf's they seldom work correctly or for long, always use oem parts such as Bosch or Seimens. Maf's do not always set fault codes so don't rule it out. These engines require a sealed vacuum system to run correctly, air leaks create running problems due to unmetered air getting picked up by the exhaust sensors which in turn causes the fuel trims to go high trying to compensate for what it sees as a weak mixture. It will add fuel up to about 20% before it gives up and starts setting codes.

 

[NZ00Z3]

My pick is that you have vacuum leaks to find.

- When you disconnect the MAF and the DME runs on internal table for mixture, the mixture is a little rich. The rich mixture will mask the vacuum leaks and the car will run better. Most people take the better running to mean its the MAF, but the MAF is usually all good.

- Code 202 - O2 Bank 1 Control Limit, say that the DME has tried to adjust the mixture, but has reached its limit.

Others have given you advice already on the usual vacuum leak spots.

 

[black fingernail]

I have just changed SWMBO's intake hoses, both had small splits and the small convoluted spur on the lower hose was pretty rotten. She is still messing about now and then, so I'll smoke test it and hunt down where the leak is, I suspect the vacuum pipes.
You will find 'how to's' on you tube regarding smoke testing, I made my tester using a jam jar, electric soldering iron, rag and baby oil, epoxy putty, and a bike pump and a rubber glove! if that hasn't piqued your curiosity, nothing will !!

 

[StuCollinsUK]

Thanks so much for the insight, lots of handy things to look for here. Will have an opportunity to work on the car tomorrow as I’m changing a brake hose. RE Tony yep when I cleared the codes they all came back lots of work to do!!

 

[mrscalex]

My pick is that you have vacuum leaks to find.

- When you disconnect the MAF and the DME runs on internal table for mixture, the mixture is a little rich. The rich mixture will mask the vacuum leaks and the car will run better. Most people take the better running to mean its the MAF, but the MAF is usually all good.

- Code 202 - O2 Bank 1 Control Limit, say that the DME has tried to adjust the mixture, but has reached its limit.

Others have given you advice already on the usual vacuum leak spots.

Agree but does also look like Camshaft PS needs replacing too. Error 65 from a quick Google is the inlet side (not so sad I remember error codes) and that will cause problems more so than the exhaust.

 

[StuCollinsUK]

Ok! Finally got round to doing some removing/unplugging - I can see my idle air control hose has split (there wasn't even a clamp holding it on to the MAF end) and small cracks in several areas.

The new hose is on its way, but access to the idle control valve end looks super tricky to access, even after removing the throttle plate... (I have the M50 manifold) has anyone got any tips on changing this?

I'm also hoping it means my original MAF isn't toast either...

(Also, any links to a decent camshaft position sensor would be greatly appreciated - seem to vary in price and can't find a Bosch or Siemens one)

 

[colb]

I used a Haas camshaft sensor on a mates 3 series, fixed his problem and still going ok after a year.
Just had a look at Carparts4less and Europarts but couldn't find any for your 2.8 however GSF show a choice of two makes of sensor, one a GSF Standard and the other a Delphi, neither are cheap

 

[Dakar Z3]

Google MEYLE, go to online catalogue and put 314 899 0010 in to the parts look up box on the left side of the page, this will bring up a picture of the part and give application details, You do not need to fill in any other detail, check to see if it looks like your sensor, if it is try AtoZ in Huddersfield, call 07707 164642 and speak to Asam, tell him John recommended you from MEYLE, he will check for you and offer a discount, Good luck

 

[Markie]

Hi guys, having some running/stalling issues and would like to get your thoughts (m52 1998).


Brief description of how the car has been behaving...revs pulling low when idling, can drive it but when coming to a stop the car stalls most of the time. Will fire back up again but will repeat this behaviour.

I unplugged the mass air flow sensor and the car ran immediately better, so by default thought it needed replacing.

Bought an aftermarket MAF and it was getting the mixture all wrong, presumed it was garbage - to rule it out swapped another MAF off my dads M52 2.8, but it went back to dropping revs and the stalling issue...


Plugged in to a computer and the following codes appear (MAF did not show when plugged back in and codes cleared):


217 - CAN: Timeout AGS/Electronic Transmission Control (EGS)

55 - O2 Sensor 2 Heater Before CAT

65 - Camshaft Position Sensor

52 - Exhaust Flap Solenoid Valves

202 - O2 Bank 1 Control Limit


Obviously would like to address all of these at some stage, but does anyone have any insight as to which is directly the culprit causing low pulling revs/stalling?

I’m guessing the reason it runs better without the MAF plugged in is the default programme the car is using also overrides the main culprit?!


Many thanks in advance!


Stu

 

[Markie]

Try Soper BMW in Lincoln, they are very supportive of Z3 owners.offer a discount and the genuine article works and lasts.I know through the phrase Buy cheap,Buy twice.

 

[Dakar Z3]

That’s a phrase I would use, ‘buy cheap buy twice‘, Quite right too hence the reason why I would only purchase or recommend proven trusted brands with manufacturing capability, ZF, Sachs, Lemforder,SKF, Meyle, Brembo, Bosch, Valeo, Corteco etc