S54 Swap Question

[FredK]

Well the S50US/52 will definitely run without a cam position signal, albeit poorly. Besides a good ground, it will basically spark if it knows where the pistons are (crank position sensor).

I agree that the stock in-tank pump merely feeds the main pump, which does the "heavy lifting" for the fueling system. I am fairly certain a Walbro 255 will be adequate for the purposes of this swap. People run the S50B32 in an E36 using the stock 3.5 bar fueling system. It's not ideal, however, but the car will turn over.

Have you attached the accelerator pedal?

[E30Strube]

The accelerator pedal is connected.

Am I seeing all of the grounds...motor mount arm to car, Engine Harness (bundle of 3-4 grounds), DME pin 5, one of the pins off the E30 to E46 adapter for the windows/locks. I also connected a ground from the battery tray area to the head of the S54. All connectors are connected for the items I have on the engine. I will be testing the Crankshaft Position sensor wiring tonight to make sure it is correct. I lengthened several wires on the X6003 connector, but each is connected where it should be.

[nando]

all it really needs is a load signal (TPS at minimum) and crank position signal to "run" (coolant temp helps too, but it will substitute a base value if no signal is present).

Freddykins, you said check for voltage at pin 1 of x6004.. that's the battery charge indicator. surely you meant something else. :p

before you go on a wild goose chase for signals though, make sure the DME is actually getting power. The important grounds are all on X6001 (pins 4-6). There are like 5-6 power wires you need. Off the top of my head, pins 7-8 of X6001, pin 23 on X6002, and 6 & 26 pins on X6004. the other grounds are signal/output grounds and aren't needed to power the ECU. These are strictly what is needed with the key on, for the ECU to be powered up (not neccesarily for it to start and run).

the next step would be to check for a crank signal. It won't power the FP (except for priming it for a second at key on) or spark until it sees RPM.

[328ijunkie]

S54 runs 5 bar fuel setup IIRC

[nando]

yeah, I was going to say - if the walbro works up to 70psi, the S54 needs ~73psi *stock*. And I hope that 70psi rating on the walbro isn't it's maximum operating pressure, because that means the flow rate will drop and fuel temp will increase. From data I've seen, the walbro doesn't like running at high pressure very much.

anyway, maybe it works, but it's going to be on the edge..

[FredK]

Freddykins, you said check for voltage at pin 1 of x6004.. that's the battery charge indicator. surely you meant something else. :p

before you go on a wild goose chase for signals though, make sure the DME is actually getting power. The important grounds are all on X6001 (pins 4-6). There are like 5-6 power wires you need. Off the top of my head, pins 7-8 of X6001, pin 23 on X6002, and 6 & 26 pins on X6004. the other grounds are signal/output grounds and aren't needed to power the ECU.

Yikes, you're right. X60004 pin 1 is the battery charge indicator.

The DME is powered at pin 7 and 8 on X60001. It should be an "always hot" at X60001 pin 7, as it's Terminal 30 and should be continuous with the battery positive (B+).

X60004 pin 26 and X60001 pin 1 are "power with key on". X60004 pin 6 is the start signal and needs to be hot only while starting.

[goarmy]

I'm not getting fuel and the engine isn't starting. It will turnover, but not crank. Since I have an E30 M3, I still have the 4 cyl module in the cluster. Would not changing it cause no rpm signal and no start?? The starter is seeing 12V as is the fuel pump relay. There is nothing at the inline pump.

before the pcm main check cam and crank sensor the signal output and all other sensor is read and sent to ignition coil. check the cam rotation if any at all, open the the cap and see, if no rotation no compression might have your timing off from cam to crank arent correct check the timing points.. check the ingnition coils take the coils out and on crank check for spark o get a tester light and check the injectos voltage output supply that should tell you if the computer has operating voltage and injector trigger signal. goodluck man

[nando]

Yikes, you're right. X60004 pin 1 is the battery charge indicator.

The DME is powered at pin 7 and 8 on X60001. It should be an "always hot" at X60001 pin 7, as it's Terminal 30 and should be continuous with the battery positive (B+).

X60004 pin 26 and X60001 pin 1 are "power with key on". X60004 pin 6 is the start signal and needs to be hot only while starting.

yeah, pin 6 should cause it to energize the main relay. and it definitely won't turn on without 26 activated (even if you apply power to all the other neccesary pins - man, that lead to a "durrrr" moment).

[nando]

before the pcm main check cam and crank sensor the signal output and all other sensor is read and sent to ignition coil. check the cam rotation if any at all, open the the cap and see, if no rotation no compression might have your timing off from cam to crank arent correct check the timing points.. check the ingnition coils take the coils out and on crank check for spark o get a tester light and check the injectos voltage output supply that should tell you if the computer has operating voltage and injector trigger signal. goodluck man

it doesn't need the cam signals to run.. just the crank. of course it will be in batch fire mode and vanos won't be working, but it will start and run "normally".

[goarmy]

it doesn't need the cam signals to run.. just the crank. of course it will be in batch fire mode and vanos won't be working, but it will start and run "normally".

hey good to hear from you again I expect everything is running along.. engine is accuired yet?

[nando]

nope - still working out the electronics. :(

[kalib0y]

Electronics...the best part of the swap...not.

Hope you get it figured out. have you checked the injectors to see if they are shooting? Check for spark?

[nando]

actually, I think it is. :D

[Wanganstyle]

Electronics...the best part of the swap...not.

Electronics is the BEST part of the swap. :)

knowing how the systems are integrated is the best feeling one can have!

Why not use the S54 native 5.0 bar fuel pump? Walburrito's are used for Japanese cars with lower pressure fuel systems (43.5psi or slightly more)

[E30Strube]

As a follow up to this...I realized I had some wires that were not connected. Three red power wires (ECU power) and two other connectors that didn't appear to connect to equipment, actually connected to two other connectors. Got everything wired up and the car will start, but dies after a few seconds. This goes on about 3-4 times and then the key will no longer make the attempt to crank the car. Each of the times it starts, the car will run for different periods of time, ranging from 2-5 seconds. I will pull the codes tonight as well as check the fuel system further.

I'm thinking the possibility is that the pumps are coming on with the key in the ACC position, pressurize the system, the car starts, the pumps cut off, and then the car is only running while there is fuel in the line.