[E38] 740i engine dies and runs on 6 cilinders - BMW Forum - BimmerWerkz.com
BMW Forum BMW Forum

Auto Insurance

» Featured Product
Wheel & Tire Center

Go Back   BMW Forum - BimmerWerkz.com > BMW Model Specific Forums > 1,6,7,8 - Series and Mini Cooper
Register Home Forum Active Topics Gallery / Showroom Auto Loans Garage Search Today's Posts Mark Forums Read Auto EscrowInsurance

1,6,7,8 - Series and Mini Cooper General Chat related to models that do not fit into particular categories above. Please try to put your discussion in more appropriate sections. This section does cover the 1 Series, MINI Cooper and 8-Series vehicles: BMW 830i, BMW 840Ci, BMW 850i, BMW 850Ci, BMW 850CSi, M8, Alpina B12, BMW CS Concept and others.

BimmerWerkz.com is the premier BMW Forum on the internet. Registered Users do not see the above ads.
Reply
 
LinkBack Thread Tools Display Modes
Old 01-17-2010, 08:18 AM   #1 (permalink)
n00b
 
Join Date: Jan 2010
Car:
Posts: 21
Photos:
revot360 is on a distinguished road
Unhappy [E38] 740i engine dies and runs on 6 cilinders

first post so here i go..

i recently bought a 95 bmw 740i. it has an aftermarket LPG-g3 lpi installation in it.

when i bought the car it already didnt sound nice but i thought it would be an easy fix.(but its not i guess)

when the engine is cold (after 8 hours) it starts direct but sounds like it runs on 5 or 6 cilinders. then when its hot when i turn the key it takes about 10 seconds before it starts.. still only 5 to 6 cilinders..

i dont know if the lpg has anything to do with it. it runs just the same on gasoline as it does on lpg.

the dealer has looked for any fault codes but it doesnt have any??

anyone has a suggestion?

im getting a new CPS in a day or 2.. but dont think this will fix it.

also the car just died after startup this morning.. tried it a couple of times. the rpm stays around 400..
revot360 is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old 01-17-2010, 09:12 AM   #2 (permalink)
Help from over the pond
 
marti5's Avatar
 
Join Date: Sep 2008
Location: IPSWICH. U.K.
Car: E38 1997 728i Individual
Posts: 3,242
Photos:
marti5 is on a distinguished road
It could be your MAF, but that would show a code, I would say its to do with the LPG system, I have come across a lot of problems conerning 5 & 7 series with an LPG system fitted, your best option would be to take it to an LPG service centre. However if there's a way to isolate the LPG try that first.
__________________
VELVET BLUE UK INDIVIDUAL , IM THE LAST
UNITED WE STAND DIVIDED WE FALL

I stepped in a plate of Pasta the other day - now I have to worry about my Carbonara footprint!
marti5 is offline   Reply With Quote
Old 01-17-2010, 09:37 AM   #3 (permalink)
n00b
 
Join Date: Jan 2010
Car:
Posts: 21
Photos:
revot360 is on a distinguished road
i have checked with the lpg install removed by just disconnecting the power going to the lpg control module.

the problem remains..

also a couple of days ago when i was comming home from work it showed "getriebenotprogramm" this was the transmission running at safemode..

the next day i started it was running normal again and i havend had it anymore.

that day it was very cold outside. maby thats what triggered it ?
revot360 is offline   Reply With Quote
Old 01-17-2010, 01:38 PM   #4 (permalink)
Help from over the pond
 
marti5's Avatar
 
Join Date: Sep 2008
Location: IPSWICH. U.K.
Car: E38 1997 728i Individual
Posts: 3,242
Photos:
marti5 is on a distinguished road
Hmmm... I know its not what you want to hear but LPG and V8's just don't go together, get rid of the gas then with help from here she will run as she should...she never will on gas....or should I say may for a while...

It was designed by engineers to run on petrol not gas...I will say no more, apart from don't buy a V8 and then worry about the running costs !!! false economy?
__________________
VELVET BLUE UK INDIVIDUAL , IM THE LAST
UNITED WE STAND DIVIDED WE FALL

I stepped in a plate of Pasta the other day - now I have to worry about my Carbonara footprint!
marti5 is offline   Reply With Quote
Old 01-17-2010, 04:14 PM   #5 (permalink)
42, The meaning of life
 
brettski's Avatar
 
Join Date: Jul 2009
Location: Melbourne, Australia
Car: 2000 740iL Individual
Posts: 2,405
Photos:
brettski is just really nicebrettski is just really nicebrettski is just really nicebrettski is just really nicebrettski is just really nice
Did the previous owner give you any insight into the history of the problem?

Have you looked at the spark plugs to establish if it is consistent in which cylinders are not firing, it might have something to do with the iginition system if two or three of the plugs are showing signs of being unignited. Given that the problem is consistant on LPG and Petrol, I'd look at the common systems first, plugs, leads & HV packs.
brettski is offline   Reply With Quote
Old 01-17-2010, 06:43 PM   #6 (permalink)
n00b
 
Join Date: Jan 2010
Car:
Posts: 21
Photos:
revot360 is on a distinguished road
i got some details from the last owner but i dont believe the bills he gave me ar from this car.. i have a bill of 4 new spark plugs.. seems kinda weard on a 8 cil car..

but tomorrow i wil have a look at the sparkplugs and i will look if i can check the MAF..

iim thinking to just dissconnect the MAF when its running to see if te computer does indeed detect the faults..

i

thanks for all the help and tips you guys have given me

ill let you know if i find the problem
revot360 is offline   Reply With Quote
Old 01-17-2010, 10:30 PM   #7 (permalink)
42, The meaning of life
 
brettski's Avatar
 
Join Date: Jul 2009
Location: Melbourne, Australia
Car: 2000 740iL Individual
Posts: 2,405
Photos:
brettski is just really nicebrettski is just really nicebrettski is just really nicebrettski is just really nicebrettski is just really nice
I am not sure if it applies to the more modern injected LPG conversions, but the old mixer style units required a different spark plug to the petrol only engines, so it may be worth checking that the "correct" plugs are installed.
brettski is offline   Reply With Quote
Old 01-19-2010, 08:52 AM   #8 (permalink)
n00b
 
Join Date: Jan 2010
Car:
Posts: 21
Photos:
revot360 is on a distinguished road
i have now changed the CPS.. the car doesnt die anymore but still it doesnt run smooth..

the RPM shakes around 400 to 600.

i also disconnected the MAF while the engine was running.. the engine didnt change in rpm. also no check engine lights came on..

it seems it doesnt respond to any errors at all

i also did the obd test nr.2 to check all the lights in the dash.. the check engine light doesnt work?? is this normal ? all the other ones work in the test..

i also got 8 new NGK spark plugs..

i think i will fit them tomorrow to see if there is any improvement.
revot360 is offline   Reply With Quote
Old 01-19-2010, 08:30 PM   #9 (permalink)
42, The meaning of life
 
brettski's Avatar
 
Join Date: Jul 2009
Location: Melbourne, Australia
Car: 2000 740iL Individual
Posts: 2,405
Photos:
brettski is just really nicebrettski is just really nicebrettski is just really nicebrettski is just really nicebrettski is just really nice
Maybe the Check engine light is burnt out (if it was on a lot)
Good luck.
brettski is offline   Reply With Quote
Old 01-20-2010, 03:19 AM   #10 (permalink)
Help from over the pond
 
marti5's Avatar
 
Join Date: Sep 2008
Location: IPSWICH. U.K.
Car: E38 1997 728i Individual
Posts: 3,242
Photos:
marti5 is on a distinguished road
At this point I would have a diagnostics done, as it sounds like someone has messed with check engine light or it has burnt out like Brettski has mentioned, when the MAF is unplugged it should run like a pig...it maybe that its on 02 sensor, diagnostics would put you in the right direction or you could be messing about for ages and spending money on parts that are not required.
__________________
VELVET BLUE UK INDIVIDUAL , IM THE LAST
UNITED WE STAND DIVIDED WE FALL

I stepped in a plate of Pasta the other day - now I have to worry about my Carbonara footprint!
marti5 is offline   Reply With Quote
Old 01-20-2010, 05:32 AM   #11 (permalink)
n00b
 
Join Date: Jan 2010
Car:
Posts: 21
Photos:
revot360 is on a distinguished road
is there a way i can trigger the check engine light? to make sure ist busted?

witch sensor could i dissconnect to make it light up?

would the CPS do this?
revot360 is offline   Reply With Quote
Old 01-20-2010, 06:27 AM   #12 (permalink)
Help from over the pond
 
marti5's Avatar
 
Join Date: Sep 2008
Location: IPSWICH. U.K.
Car: E38 1997 728i Individual
Posts: 3,242
Photos:
marti5 is on a distinguished road
Where do you live as Ive just notice you had "getriebenotprogramm" come up are you in Germany?, the reason I ask is that older european 7 series dont have the EML light fitted!!
__________________
VELVET BLUE UK INDIVIDUAL , IM THE LAST
UNITED WE STAND DIVIDED WE FALL

I stepped in a plate of Pasta the other day - now I have to worry about my Carbonara footprint!
marti5 is offline   Reply With Quote
Old 01-20-2010, 08:28 AM   #13 (permalink)
n00b
 
Join Date: Jan 2010
Car:
Posts: 21
Photos:
revot360 is on a distinguished road
i live in holland.. its an original dutch car that came in german language..
revot360 is offline   Reply With Quote
Old 01-20-2010, 09:58 AM   #14 (permalink)
Help from over the pond
 
marti5's Avatar
 
Join Date: Sep 2008
Location: IPSWICH. U.K.
Car: E38 1997 728i Individual
Posts: 3,242
Photos:
marti5 is on a distinguished road
Ok, The SES light indicates an engine fault that will cause raised emmisions, such has a misfire, air-leak etc. In certain countries it is called the OBD (On Board Diagnostics) indicator and has the same function as the SES light. If it doesnt come on then you dont have a problem with the above...

What I would do next is clean the throttle body and MAF, also for any air leaks even though the light is not on,,,there is a gasket that sometimes fails between the throttle body and intake manifold check this if its hard or cracked it will let air in the system..
__________________
VELVET BLUE UK INDIVIDUAL , IM THE LAST
UNITED WE STAND DIVIDED WE FALL

I stepped in a plate of Pasta the other day - now I have to worry about my Carbonara footprint!
marti5 is offline   Reply With Quote
Old 01-20-2010, 07:29 PM   #15 (permalink)
42, The meaning of life
 
brettski's Avatar
 
Join Date: Jul 2009
Location: Melbourne, Australia
Car: 2000 740iL Individual
Posts: 2,405
Photos:
brettski is just really nicebrettski is just really nicebrettski is just really nicebrettski is just really nicebrettski is just really nice
Were the old plugs able to indicate that some of your cylinders weren't firing properly?
Did the new plugs make any difference to the problem?
brettski is offline   Reply With Quote
Sponsored Links
Advertisement
 
Reply

  BMW Forum - BimmerWerkz.com > BMW Model Specific Forums > 1,6,7,8 - Series and Mini Cooper


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
fs 1995 e38 740i activee387 Cars For Sale 3 09-16-2009 09:13 AM
E38 740i Diff Ratio? bobwatt 1,6,7,8 - Series and Mini Cooper 2 09-16-2008 08:23 PM
E38 740i Power Issue Lexx_DMC 1,6,7,8 - Series and Mini Cooper 5 09-11-2005 09:29 PM
Fs: 2001 E38 740i Sport carmaniac Classifieds Sell & Buy 7 02-11-2005 06:25 AM
Wtb: E38 740i Or 740il carmaniac Classifieds Sell & Buy 0 11-17-2004 02:01 PM

Powered by vBadvanced CMPS v3.2.2

All times are GMT -5. The time now is 04:12 AM.



Powered by vBulletin® Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Content Relevant URLs by vBSEO 3.3.2
Garage Plus vBulletin Plugins by Drive Thru Online, Inc.