E36 idling issue

[abharoochi]

Hi guys,

i recently did an engine swap on my e36. i replaced my m43 with and m42. i am using my old ECU and the car starts and gives on erratic rev and then cuts out... if i try and give petrol it tries to idle but smothers out

Any idea what it could be?

 

[skyb3r]

If you open up your engine compartment and look to the bottom right, you will find your MAF. On top of your MAF there is a small lid that can be removed with a small flat screwdriver.
You will then find a small 7mm bolt keeping the spring loaded controller in place, remove that and your spring should jump loose.
Then try and start her up while keeping revs. Slowly turn the spring clockwise untill you get a near perfect idle.

One question tho, why swop the M43 for the M42? It wont really.make a significant increase in performance.
Maybe a S14 Engine with branches and CAI is.a better choice:thumbs:

 

[abharoochi]

Thanks...

Bit of a long one but here goes...

After owning the car for a few days the motor packed up - so bad even a hole melted through one of the pistons. Then even more bad luck was the dodgy machi that could not be found after he had stripped out my motor.

After months of moping around my dad came home one day and said hey! check in the garage i want you to have a look at something for me - and to my surprise he had bought me a motor complete with gearbox, loom and ecu - the only mistake he made was getting the M42 and not M43 and i wasn't going look a gifted horse(sorry Pops) in the mouth.

So far all fit snug as a bug and the fact that it starts :rollsmile:
all that is needed is some tweaking i guess

Fyi - If i compare the 2 i should feel a slight difference (i stand to be corrected)

Engine Displacement Power Torque Redline Year
M43B16 1596 cc 75 kW (101 hp) @ 5500 150 N·m (111 lb·ft) @ 3900

Engine Displacement Power Torque Redline
M42B18 1,796 cc 103 kW (140 PS; 138 hp) @ 6,000 175 N·m (129

Cheers:thumbs:

 

[skyb3r]

Oh sorry, I thought you were refering to the M43B18 engine wich has about 20kw more than the M43B16 if tweaked right.

I hope shes on the road soon tho, goodluck bro:thumbs:

 

[abharoochi]

Thanks bro - i hope so too been way to long

Hoping to have it done in this week:rollsmile:

 

[Gizmo]

You need to run the M42 with the M42 ecu. What issue you are probably running into is the M43 probably has EWS and the M42 does not. Did you get the M42 with its "barn-door" air flow meter?

 

[abharoochi]

Gizmo, please excuse my stupidity - barn door?

Motor came with its own MAF and ecu - but would not start. When i changed to the cars's original ecu it started up and im able to rev but then cuts out. I take it this is due to the ews...

 

[madness_inc]

Gizmo, please excuse my stupidity - barn door?

Motor came with its own MAF and ecu - but would not start. When i changed to the cars's original ecu it started up and im able to rev but then cuts out. I take it this is due to the ews...

Barn Door style MAF/AFM
Bottom right corner, behind the cone filter

---

One question tho, why swop the M43 for the M42? It wont really.make a significant increase in performance.

The 16v M42 is far superior to the 8v M43

 

[abharoochi]

:rollsmile: LOL my bad...

Yes it came with one like that...

 

[madness_inc]

:rollsmile: LOL my bad...

Yes it came with one like that...

As gizmo said, run the M42 with the M42 ECU.
It's kinda like asking an 325i ECU to know how to run an M3 motor... not going to end well

 

[abharoochi]

Okay, but i tried that and it would not turn... i have a feeling its coz of the EWS - should i have this bypassed? First of all can it even be done??

 

[Gizmo]

Gizmo, please excuse my stupidity - barn door?

Motor came with its own MAF and ecu - but would not start. When i changed to the cars's original ecu it started up and im able to rev but then cuts out. I take it this is due to the ews...

M43 ecu is not designed to run the M42 as the AFM, ICV and a few other sensors are completely different with different resistance values. The fact that the M42 started on the M43 ecu is amazing.
Perhaps a wiring difference in the body harness or something, can't help more without seeing the car unfortunately.

 

[madness_inc]

Okay, but i tried that and it would not turn... i have a feeling its coz of the EWS - should i have this bypassed? First of all can it even be done??

You can have the EWS bypassed. Quite common on older E36s these days. Speak to Gizmo, he is our resident E36 guru.

Some more information for your perusal
http://forums.bimmerforums.com/foru...I-EWS-II-delete-bypass-and-information-thread!

http://www.bimmerfest.com/forums/showthread.php?t=536505

 

[abharoochi]

Thanks alot guys!!! Will see how far i get this week.... so hope i get it sorted, we have a meet and great on Sunday here in the Cape!!!:rollsmile:

Will keep you guys posted:thumbs: