BMW Turbo Discussion  - BMW 745i and BMW Turbo Project Forums
User Name:
Password:
Save Password
Forgot your Password?
Home | Active Topics (0) | Members | Online Users | Statistics | File Library | Search | Avatar Legend
 All Forums
 The e23 745i and Turbocharged BMW Motor Topics
 BMW M106/M102/M30 Turbo Topics
 M106 shoking on Full throttle between 4000-5000rpm
Next Page
 New Topic |  Reply to Topic |  Bookmark Topic |  Printer Friendly
Author Previous Topic Topic Next Topic
Page: of 6

superbass
Starting Member

Status: offline


40 Posts

Posted - Mar 28 2013 :  00:03:45  Show Profile  Reply with Quote
Hi guys New to this Forum and i got a really old Problem that till date i cant find its solution
i Got a bmw m3 e30 1987 with an M106 L-jtronic 3.5l on a 3.2/3.5l engine head with a manual transmission All parts are Stock, now my prob is that the car idle very smoothly it accelerates smoothly its flawless when accelerating BUT if i go FullThrottle the car Shokes badly starting on 4000rpm to 5000rpm and it wont rev more it Shokes like if its missfiring on all cylinders feels like the engine will blow to peaces, Now if i Remove the full throttle pin of The TPS the car runs normal even on full throttle it will hit 6800 rpm no prob but if i put it back it starts shoking again ...
Parts Replaced :
3 ecu units
tank fuel pump
outside fuel pump
fuel filter
injectors
fuel line
fuel regulator
AFM
TPS
distributor
spark plugs 4 times
spark plug wires
ignition coil
Vaccum hoses (bypassed some of them still nothing)

problem is the same on cold and hot
Vaccum is stable
Fuel pressure stable at 2.5bar(Raised it to 3bar no change) (bypassed the regulator still same)
Raised the boost to 0.7 bar still no change
Bypassed the waste gate Still nothing
the whole motor has been dissassembled 3times so far the prob never changed
Cheked for leaks all over
Tested electrical wiring with different experts
went through many garages no luck

i searched for hours to find an electrical wiring diagram of the ecu of the L-jetronic but i cant find any i found the full Motronic but its not the same if anyone can provide me on the electrical wiring of the engine id be thankful


Waiting any answer dont hesatate to ask anything kind off desprate its been 7 years on this engine, i had a same engine as this before as well same configuration but on 1.1bar boost broke 5 pistons on it but the car was still running when i took it to the shop i had to travel and the mecanic took my engine out and swaped it with this one and its been crap since then kind off waiting for a miracle

sory for my english and thanks for any help

greg_mazur
Over 745 Posts!

Status: offline


1234 Posts

Posted - Mar 28 2013 :  14:46:07   View greg_mazur's Photo Gallery  Show Profile  Reply with Quote
When you go to full throttle and the engine cuts out is this in neutral gear stationary or is the problem only on the road at speed?
Go To Top Of Page

superbass
Starting Member

Status: offline


40 Posts

Posted - Mar 29 2013 :  00:06:09  Show Profile  Reply with Quote
it happens at both on nutral its fix at a certain rpm depending on the afm position on gear its not fix it starts on 4000 and becomes harder till 5000 or so and stops there

Edited by - superbass on Mar 29 2013 00:07:57
Go To Top Of Page

greg_mazur
Over 745 Posts!

Status: offline


1234 Posts

Posted - Mar 29 2013 :  04:33:11   View greg_mazur's Photo Gallery  Show Profile  Reply with Quote
It seems you have spent a good deal of time "fixing the problem" without ever trying to discover what the problem is. Most likely your ignition or fuel system is dropping out.
Outside of that you may have a mechanical problem with the engine but that appears unlikely since you say it runs ok otherwise. Since it acts up in neutral, put a timing light first off the coil to dist, a fuel pressure gauge right at the injector rail. Run the engine up till fault level and watch for any abnormality on your test equipment. Need to spent as much or more time diagnosing a problem as time spent actually making the repair. If you find nothing move the timing light to each plug. As for the throttle switch it passes ground level to the ecu so check that the switch incoming wire is indeed at ground level and the wire end from the throttle switch out to ecu is at the same level . Outside of this just as the engine faults shut it down and pull each plug and inspect for visible indication of too much fuel, unburnt fuel etc. Have you done a compression test, checked out the turbo and lower hose connection?
You have stock parts as you say but far from stock bmw , it is going to be hard for outside help to figure this out. For example do you have the entire L jet wiring, dist, ballast resistor, ecu ? Cause it never was factory paired to a manual trans. Keep at it let us know.

Edited by - greg_mazur on Mar 29 2013 04:37:58
Go To Top Of Page

superbass
Starting Member

Status: offline


40 Posts

Posted - Mar 29 2013 :  10:19:39  Show Profile  Reply with Quote
ok hope i dont miss out on all that u mentioned
-i did a cylinder compression rate all are equal almost perfect
-tps wiring where examened more then 5 times with equipment and compared with an other jtronic m102 engine as well
-spark plugs where removed after installation and a test of the problem coloring of the spark plugs is normal
-already have a gauge to the fuel rail pointing 2bar at idle and 2.5bar once i hit the throttle ( bypassed it to 2.5 bar all the time no change)
-got a boost gauge as well boost and vacum are very stable no flikering nothing out of the normal
- The timing light tester is a good idea already got the equipment will try that in the morning ! duno why i didnt think hope i get anything will post back in 12 hours on that
Hope i covered it all but i had already replaced the whole items the coil-resistence-wires-and the distributor the only thing that i didnt find was the spark amplifier duno what its called duno what symptoms would that cause if defected [/red]
and ill check the parts codes tmrw as well ( But note that this configuration and the whole system was working on my old m106 was perfect even on 1.1bar boost)
i had tried to diagnose the prob
fuel is checked
vacum leaks are checked
wiring and voltage... where checked
The only thing that i couldnt figure out is the afm on the last part of the afm the problem will occur once the needle would reach the last part of the afm but i replaced the afm and still on the last part the prob will occure i dont know what this is related to ( i can adjust my afm the cap was opened to try as well if i tight it or loosen it the hesitation will shift to diferent rpm's but this only occurs if at "Full throttle" its frustrating

Edited by - superbass on Mar 29 2013 10:42:11
Go To Top Of Page

superbass
Starting Member

Status: offline


40 Posts

Posted - Mar 29 2013 :  12:58:51  Show Profile  Reply with Quote
-Also i forgot to mention im prety sure its not fuel related 99% sure cz i removed all 6 injectors out the engine head turned them with the rail up side down turned the ignition key on and turned the afm on the full band from 0 to max worked perfectly no driping and no hesatation at all even on the last band of the afm with the tps wire in
-bypassed the cold start injector suspecting for leaks no change as well
Go To Top Of Page

greg_mazur
Over 745 Posts!

Status: offline


1234 Posts

Posted - Mar 29 2013 :  16:00:55   View greg_mazur's Photo Gallery  Show Profile  Reply with Quote
Also try putting the timing light on the front dampened and as the rpm rise it should
Advance and hold there without any sudden waver. Also a long shot but sometimes old
Motor mounts will allow the engine to rock and move at high rpm and bind or twist wiring. Try watching the engine rise in rpm in the dark and watch for electrical shorts.
I think this is a ignition problem because a loss of fuel would be less of a sudden effect on the engine and not cause shaking but rather a slower loss of power.
Go To Top Of Page

greg_mazur
Over 745 Posts!

Status: offline


1234 Posts

Posted - Mar 29 2013 :  16:02:58   View greg_mazur's Photo Gallery  Show Profile  Reply with Quote
You also have the two flywheel sensors to suspect. Any other visual indications at high rpm such as black smoke from exhaust . With all the lighting on is there any change in
Lamps, have you tried no boost at all?

Edited by - greg_mazur on Mar 29 2013 16:52:54
Go To Top Of Page

superbass
Starting Member

Status: offline


40 Posts

Posted - Mar 29 2013 :  22:00:46  Show Profile  Reply with Quote
It does smoke when that hapens
Checked for electrical shorts nothing changes when the problem occures
As for sensors i dont have any sensors on the car ljetronic dont have sensors
Tried no boost same thing boost and vacuum donsent afect it
Changed the batery 6month ago
All ground conections to the body where cleaned
And i tested all the wires coming to the ecu tps afm for bad conections or if they are touching ground or each other none vame wrong + i had run an elecrtic diagnostic test
On the l-jetronic tester in a garage i had some wrong conections all fixed but nothing changed and tested voltage on diferent parts on tps afm injectors all was good
and replaced the ecu after that and no change
I wish i could find the wiring diagram of the system so i can be 100% sure its not a wrong conection but cant find any
Will put the timing light on in a few hours and post back
And thank you so much for helping me figure this frustrating problem

Edited by - superbass on Mar 29 2013 22:02:45
Go To Top Of Page

superbass
Starting Member

Status: offline


40 Posts

Posted - Mar 30 2013 :  00:43:31  Show Profile  Reply with Quote
Ok Results on Timing Light test
-i put the light on all 6 spark plugs all 6 looks the same on all rpms
-but when i put in on the main coil wire on idle the light is dim and stable but when rising the rom u can clearly see some dead spots between the rising rpm even on low stable rpms u can clearly spot some dead spots i dont know if thats my eyes showing this cause of the frequency but i kept rising with the rpms also noticed once i hit the shocking point the light dims a little and also has some diying spots
now considering this whats related to that taking the fact that i have changed
-spark plugs + wires
-main coil
-ignition resistence
-the distributor + cap + ( the thing that rotates inside it duno whats it called)
The only thing relating the ignition system non replaced is the egnition module BOSH 0 227 100 025 Could this be the prob ?
and Considering it is the PROBlem is there any other ignition module from other bmw models or a different number i can replace it with ? cause i didnt find a module like this one to replace before :/
Go To Top Of Page

greg_mazur
Over 745 Posts!

Status: offline


1234 Posts

Posted - Mar 30 2013 :  05:53:11   View greg_mazur's Photo Gallery  Show Profile  Reply with Quote
Yes your right no flywheel sensors that's motronic. Black smoke is a missed combustion event , could be ignition or valve problem or valve timing, but you say all is ok when you remove one tps wire. So we assume engine internals are ok? Does the timing light strobe change at the coil with and without that tps wire connected?
You got the right ballast resitor block
On the inner fender? You changed dist but is the drive from the engine ok. Check your timing light on another vehicle coil and see if can keep up at high rpm, then go back to your bmw. That ignition control box is very hard to come by. I have an extra and maybe we could work out a test of mine or you can maybe pick up one for yourself you need to
Have an extra anyway. Make sure your coil is getting good ground . Look over the sensor on the front pulley see if it is functioning ok. Your gathering evidence which is good before you were just swap and pray.
Go To Top Of Page
Page: of 6 Previous Topic Topic Next Topic  
 New Topic |  Reply to Topic |  Bookmark Topic |  Printer Friendly
Next Page
Jump To:

Please consider donating to help keep BMW Turbos! online.
Donate now using the link below. Thank you for helping keep the M102/M106 discussion forum alive!

BMW Turbo Discussion - BMW 745i and BMW Turbo Project Forums © Scottie Sharpe Go To Top Of Page
BMW TURBOS! generated this page in 0.77 secs. Snitz Forums 2000