200 of my 300horses have died!

Is it an E32 750i ?

If so, why do they change 5 temperature sensors? The one in the front in the grill has no influence on the ECU managment. Then there are temp. sensors for the air intake, and 2 sensors for the coolant, but one is also not important as the one giving the signal to the temp indicator in your cluster, that one also has no influence on the ECU, it is just there to show you the what I call guessometer instead of temp. indicator.

Let's start from the beginning: when you have the ignition switch in position 2 (engine still off), is the EML light on for about 2-3 seconds? If not, it will never work. Have they checked the ECU pinout for all pins and data? Was it all in accordance with the specifications?

First of all you have to find out systematically which side is bringing the problem. If you inderstand the V12 management system, that is a piece of cake. Start the engine, remove one of the plugs from the MAF. is the engine still running or not? If not, you have already the cyliner side with the problem. If no change, plug again, remove the other side and see what happens. If that kilsl the engine, you got it. Note that basically all items which are on the left side of the engine on the intake system, are working actually for the other side. Go to my website below and click on the pic of the engine then you will see that system.

Then start swopping from one side to the other. MAF, throttling valves. Unplug again the connectors and make the same check. If problem moved to the other side, you know what is wrong. Have toy checked all distributors and caps? How are the spark plus looking? Which ones are looking bad? Did you clean the throttling valves, they must run within 2% deviation rate, otherwise the engine goes into limpmode.

Maybe you answer these questions first.

 

This post is on the 7seriesforum:-

5.0 V12 Engine for sale
« on: Today at 07:34:24 AM »   

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Hi All
I have a very good complete V12 engine package on ebay, it comes with all the wiring and ECUs etc http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=4607014 772&rd=1&sspagename=STRK%3AMESE%3AIT&rd=1
I also have a lot of other parts off the same car including working suspension.
Diff, Leather and gearbox sold.
Graham

You might also post up your tech question there as there are 750 'experts' there.

http://www.7seriesforum.co.uk//index.php

 i dot think that the ECU pinout for all pins and data was checked so not sure if  it was in accordance with the specifications, just full diagnostic check which revealed no faults, so look like id shelled out

₤159.99 for sensors i never needed

o.k., here we go: MAF=Mass airflow meter http://shrubbery.student.utwente.nl/sean750/MAF_v12/MAFtroub leshooting.htm 

Battery shorting of course NOT when making a reset. Details on my page below, also the synchronisation process of the V12 throttling valves. Battery NOT shorting= remove both battery cables, cover the battery with a cloth or rubber to avoid that by accident you touch plus and minus and make a nice fireworks inside your car. The REMOVED battery cables are to be connected (best is a starter cable) and do not touch the battery please. Ignition on position 2, switch on light or hazzard lights to make the drain of last power from the capacitors faster. When these capacitors are empty, all temporary stored (or learned) data will disappear, including all fault codes, the radio code (remember that before, note it down), anti theft code etc. Thatis basically the same as with your PC when you clean it from all temporary internet files or make a reboot. Sync the throttling valve motors. See my page below.

As the problem started with the change of the dizzy to Renault Espace I would start there. I have not heard that this fits, but maybe possible. (?) http://shrubbery.student.utwente.nl/sean750/v12_cross_refere ncing/v12regularMaintanance.htm

Throttle valve, look here http://www.bimmerboard.com/forums/posts/84595/  and http://www.e38.org/e32/throttles/BMWThrottles.htm

Your tech is right what he says about the movement at the beginning. That is going/finding into default position. The motors are running constantly to react quickly to every movement of the potentiometer of the accell.

EML light in cluster/dash: with ignition in position 2 it MUST be on for about 2 seconds and then go off again. That is a check if the EML works, there are actually 2 bulbs inside the cluster for EML and one works like a kind of resistor for the other one. If the EML is not on for 2 seconds durung the starting procedure before you start engine, then automatically the engine will run in limpmode. People have paid thousand of $ to repair their 750 but the tech did not know this fact. Expensive MOTRONICs have been changed and other things. I have made a report about this http://www.bimmerboard.com/forums/posts/92132/ That's it. I am off for an overseas business trip from tomorrow and will be back in 10 days and hope to read about a good result. Go first for the dizzy cap, maybe he still has the old one and try that once  more. 

 

Hi there. I am in the airport now, just a last info before going into the plane:

you have got so far the indication WHICH side is wrong, that is all. If the MAF's are switched from one side to the other, then the MAF is the prob. If not, change the throttling valves, they are interchangeable. So you know which side, if you see it positive, that is 50% of the engine prob is solved by now. Remember, if the MAF connector is removed from the driver side in the engine, the engine (cylinder row) on the passenger side is the problem. =The intakes go into the other side of what you can actually see from the top without diassembling. Go to my website below, there is a wonderful explosion view of the V12 engine, there you can see it and will understand what I try to explain in my poor English.

Good Luck

If you have probs, visit the boards I mentioned above and tell them what you have done so far in detail, they will guide you through it. Tell them that I introduced you, so you are not a complete stranger to them. 

Wow!!!

You guys have some serious tech skills here!! I am so gladI found this forum.

Hi shogun, to add to my problems my pc went down so I havnt been able to get on for a while right , done the maf test & right hand bank (standing at the front of car looking towards the back) stopped when maff unplugged,the left bank ran whilst i disconected that side,i changed the mafs from one side to the other,carried out test ,and again the right bank stopped & left was ok,so with that i concentrated on the throttles removed them, cleaned them as instructions from the link you left me,they were very dirty ,lots of carbon particually on the right bank side,put back together & went for a test run, economy was much better, riseing from 6mpg to 13mpg,but still underpowered ,0 to 60 mph  20 seconds !!!!(i can push it quicker than that!!),so i done the maf disconecting test again & right bank went down again , emissions test carried out & hydrocarbons(unburnt fuel) was at 7 % in the uk its a fail,shouldnt be any more than 2.5 % .Ive been really busy with work so i havnt had a chance to do any more, i think my next thing to do is change the throttles over.Or do you have any other sugestions?

One more thing to check: are you sure both fuel pumps are working? How to check under engine: http://bmwe32.masscom.net/

 

 Well ,swapped throttles over,Still the same bank goes down,the engine dont stop completely but runs very rough to the point of almost stalling, what now?!! 

Done fuel pumps, They are ok