WONT rev over 5000rpm full throttle, WILL under partial!!!

[Jibberingloon]

WONT rev over 5000rpm full throttle, WILL under partial!!!


Hmm this M50 is getting on my tits!

So was working fine a couple of month ago, but since we have done a major overhaul on it
(Adjustable Suspension / Exhaust / Engine Mounts / Fuel Lines / Removed tank and Painted it)

We are having a few issues!!!!


The car will not not rev all the way to the red line.

Seems like fuel starvation?

But not sure what to do.....

Could it be the FPR?

Could it be something to do with the Crank Angle Sensor?

Could it be something to do with the Cam Angle Sensor?

What could it be.....???


Note: the issue we also have with hot start.....
http://www.e30zone.net/modules.php?name ... c&t=219862


Help needed!!!!

Regards

Mark

[e30-EVN]

i had this on the m52, turned out to be bank 1 lambda causing limp mode

get it plugged into ethos or something similar mate and it will tell you

could be a few things, as one ecu i tried on my car did this also and that turned out to be speed signal. the wire was there (it always had been) but for some reason that ecu went into limp as it couldnt find speed signal....

[Jibberingloon]

Hmmm

Well when I got the car it didnt have any Lamda Sensors connected!

But I then put a E34 Lambda in to the manifold to see if that help and it didnt make any difference!

And the Lambda has been in there for the last couple of weeks

Hmmmmmm

Where can I find a diagnosis machine......

cheers for input

[e30-EVN]

i called into a mates garage local and he let me use his ethos. good bit of kit does live data also.

if you can get the car to a garage do so, they may charge you like 40 quid to plug it in but its better than chasing a problem by guess work and will save you money in the long run

[Jibberingloon]

True....

Well ive bought the Water Temp Sensor for DME, so plugging that in shortly to see if that works!

[E30BeemerLad]

It is a limp mode thing by the sounds of it.

Does your car have ABS? It may need a speed signal

[Jibberingloon]

Car has not got ABS......

Well all the ABS leads are cut and there is no crazy ABS Brake Line box under the bonnet.

Maybe the Temp Sensor is keeping choke on, and therefore flooding the engine at 5000rpm++....?

[Jibberingloon]

UPDATE!

Changed the Blue Sensor and nothing

So back to square one.....

FFS.....

[rich318i]

has it aways done it or just started? i had the limp mode on my m52 (non-ABS car) had to wire up to get a signal to the ECU. think its pin 9 to pin 20 or the other way around, but thats for a m52 but think they are the same but dont quote me on it

[e30-EVN]

when the one ecu couldnt find speed signal it caused all sorts of problems. 2nd gear limped out at 6000rpm, 3rd gear 5500 and 4th 5000rpm. at other times it just would not go over 5000rpm.

swapped ecu for a different item and she limped at 5500, plugged into ethos and bank 1 lambda was at fault.
but speed signal was not mentioned...

speed signal is where the money is here i'd suspect

[Jibberingloon]

where is the SPEED SIGNAL ? what sensor?

[rich318i]

it comes from the diff, c101 pin 9 to pin 20 , or what i did was run it from c101 pin to the ECU BYPASSING THE LOOM, it was pin 15 on the ECU (M52) i'm 100% on that


http://www.rmeuropean.com/bmw-e30-m50-swap.aspx

(I USED THIS SETUP ON MY M52 AND WORKS)

[Jibberingloon]

The car has only just started doing this in the last week or so.

Was running fine till we took tank off and rear beam off etc etc as I mentioned above.

So wiring should! be ok.....


If the speed sensor was playing up sure there would be no reading on the dash?

[rich318i]

how many times have you rev it to red line before you did the work tank and back end?

[e30-EVN]

my speedo still worked completly fine when the idiot ecu i had in could not find speed signal. its a dif thing. its to do with engine speed to ecu iirc as a pose to road speed......

[rich318i]

my speedo still worked completly fine when the idiot ecu i had in could not find speed signal. its a dif thing. its to do with engine speed to ecu iirc as a pose to road speed......

sorry mate engine speed is the crank sensor RPM 100% not the issue, ECU is thinking the ABS is not working, as in e36 they get the speed signal from the ABS sensor. not the diff like the E30

[e30-EVN]

yes i know that, hense why i said its a dif thing (different) not diferential. my bad on the text type

ive had this problem with my own car and i know its nothing to do with the dif which is why i mentioned my speedo worked fine as op said his speedo works....

[Jibberingloon]

Ok so shall I swap out the out to a new crank angle sensor then?

I suppose that sounds the next sensible step.

I'm also picking up another fuel pump and swapping that out at the same time.

Oh and before the work on it I've given it a death so it all worked.

The only thing I have thought is we put a straight through pipe on it and a 2nd hand stainless back box. Could the back box have collapsed and caused a blockage at high pm?

[penton08]

if you can get the car to a garage do so, they may charge you like 40 quid to plug it in but its better than chasing a problem by guess work and will save you money in the long run

This....

Swapping a Cam/crank sensor on a whim is madness. A genuine crank sensor is around £100, A cheap after market sensor might make things even worse!! Get it plugged in before you spend any more money.

[e30-EVN]

to add to that, these engines (according to a decent source) dont like cheap imitations.! so oem ones are the ones to buy

[Jibberingloon]

Was told by DanThe that the diagnosis port on these were useless....... And would give me the answer...

Will see what I can do to find a local garage with computer then.

But yes I was going to get an OEM sensor ;)

[rich318i]

to add to that, these engines (according to a decent source) dont like cheap imitations.! so oem ones are the ones to buy

100% OEM PARTS for sensors . getting put on a computer would be the first thing to do, thought you might of done that already before you came on here asking for help!! lol

[Jibberingloon]

Thought it was a simple fix that the Zoners might know but seems like it a bit of a bugger this fault I have.

[e30-EVN]

limp can be caused by a few things though mate thats the problem. we can only point you in directions, ethos will tell you straight lol

[Jibberingloon]

Ok will see if I can lay my hands on one.

[Jibberingloon]

All I've been doing is just googling and searching to find the solution to my problem......

Hope I don't get to this point!!!

Read this...

http://forums.bimmerforums.com/forum/sh ... 897&page=2


I hope I can solve it!

[rich318i]

you need to re-wire it so you can run a computer on it too see what the faults are!!!!!! arrrrrrrrhhhhhhh!!!!!!!!

[Jibberingloon]

Indeed! Lol.......

[rich318i]

use this link as i said before: http://www.rmeuropean.com/bmw-e30-m50-swap.aspx

[Jibberingloon]

Well the wiring should all be fine as it was before the fault occured, but I will check it again tomorrow evening.

[Jibberingloon]

Ok.....

Not progressing fast as little time, but checked the exhaust and there are no issues there ;)

Had a look over the wringing and can't make head nor tail of it........

Will have a proper look tomorrow.

Bloody M50 ;(

[Jibberingloon]

UPDATE!

Car is off to DanThe next week for a proper sorting!

Fingers crossed Dan works his magic!

[e30-EVN]

And that he will.!

[Jibberingloon]

well he better, because I am falling out of love with the project

[Jibberingloon]

UPDATE......
Car didn't go to DanThe as he has a bad back and I've been away on work.

However over the last week the Water pipe burst on back of block and have now fixed it!

Have now also replaced the Crank Sensor and it's still the feckin same......

What do I donor.....!