LH Module for E50 conversion

[nic520]

Hi,
my question concerns LH Modules for the conversion of an E420 to E50 M119 engine.
Startingpoint: E420 (W124), original, running fine, 100 to 200 km/h in 18,2 Seconds (GPS Timer, only one try on too crowded German Autobahn).
Engine swapped to E50 M119 engine, using Ignition and intake manifold from E420 last weekend. EZL Module from E500/S500/E60, LH Module from 500S with WOT enrichment, the one used frequently by E500 users.
Engine runs und pulls fine but comes to a kind of limiter at about 5000 rpm. It ist not the overload switch, because it does it also if reved to 5000 with second gear manually engaged and pushed smoothly, not full throttle.

I now want to test it with the LH module and EZL from the 420 to determine whether the 500 module and EZL are the cause.
My question: will that harm the engine? What are the differences between the 500 and 420 parts?
There is a german tuner who claimes the E50 engine can be run using all the 420 stuff for ignition and fuelinjection.
Does anyone know the technical differences in detail?
Appreciate any help.
Nic

 

[gsxr]

You may want to use the intake manifold from a 5.0L engine... I believe the 4.2L intake has smaller runners, and may restrict power. The 5.0L LH module and EZL are correct for this application. The trans O/L switch should not cause any RPM limit if it malfunctions.

The German tuner claiming the 5.0L engine will run correctly with 4.2L LH module is wrong. The fuel curves are different between modules. Sure, they engine may run, but it won't run properly. You can test without hurting anything but most likely there will be reduced power either at part throttle and/or full throttle.

The limiter at 5000rpm may be related to the gear position switch. Have you pulled codes (particularly from the E-GAS or T/LLR module)? Any other codes recurring after everything is cleared? I believe there will be an RPM limit around 5000 if the module does not properly recognize gear position from the NSS on the trans.

 

[nic520]

Dear gsxr,

thank you for answering! I did not know that about the NSS switch.
I will check, since I removed the plug for removing engine and tranny. It worked well before and cruise control does also work.
I have not blinked out any faults beside LH module (there are none there).
Also, i will switch back to 420 lh and ezl to check. This is the easiest way.
I thought also about the fuel filter ristricting power -but it is to precise at 5000 rpm.

Nic

 

[gsxr]

Definitely check codes on the throttle actuator module (didn't mention if your car has ASR or not). I believe there is an electronic limit to RPM by the EZL, based on a signal from the E-GAS or T/LLR, if the gear position indication is 'invalid'. This info is buried somewhere in the FSM. It's also why the engine will not rev to redline in Park.

 

[nic520]

Thank you, I will. It has ASR.
Nic

 

[nic520]

Hi,
sorry to have bothered, but the solution is simple: changed LH module and ezl back to the 420 units and it revs till redline. 100 to 200 km/h via GPS app in 15,1, just checked, compared to 18,2 seconds with the 420 engine. I have to check which module is faulty. Both come from the same 500S W140.
Thanks for your help!
Nic