Can someone help me diagnose my no start issue?

[dunebuggyjay]

Hi Guys,

Im in the process of trying to get my s52 (thats been converted to obd1) to start in my e30.

The engine did run before I pulled it, and the wiring harness out of a E36... so I know it should run.

I can hear the icv buzz, but my fuel pump does nothing. wont prime. even jumping the relay, It doesnt turn on. (if I put 12v right at the pump, it works so Im sure the pump is good (its brand new aeromotive 340)

Car does turn over. just no fuel.


When I opened the DME there is a tiny bit of corrosion from water, so I am thinking at this time it may be the DME causing my car not to start.


Would a faulty DME cause the pump to not run (even when jumping the relay?)

I wish I new someone that had a working red label 413 I could try, before spending 70 bucks on another one that may be junk also.

Anyone have any suggestions? I have heard something about the OBC causing it to not start. Thats my next task tommorow, to try and unplug that.....but I am not really sure thats my issue.

Ive triple checked the harness (I re-pinned the plug) and all seems well.

Thanks
Jay

[mpowerful]

If you have anything but a vert check the fusible link as it directly powers the fuel pump relay. On a vert there is a specific wire that hooks right to the battery terminal.

[dunebuggyjay]

If you have anything but a vert check the fusible link as it directly powers the fuel pump relay. On a vert there is a specific wire that hooks right to the battery terminal.

Thanks, Ill check that.

I never thought to check that little wire to make sure its got 12v for the DME.

I do have a vert, but while I did the engine swap, I put the battery in the back. (I used the large power wire, and the smaller wire from a sedan donor car i had.)

Is the fusable link on the smaller wire?

I used the original vert battery terminal to attach it the large power wire coming from the trunk (from a sedan). The only wire I have going to the little power wire in the trunk is what i thought was the power for the DME. (the one thats right before the diag port on the e36 wire harness.)


Thanks,
Jay

[mpowerful]

One of those small wires is a ground too. Your best bet is to run the single heavy gauge wire to the front then run a distribution

[mpowerful]

Block to keep up with the power wires.

[M3PO]

If you jump the fuel pump relay, the pump should run regardless of the DME. That's what happened to me when EWS was keeping the DME from triggering the pump.

[dunebuggyjay]

Okay, here is what i am finding:

Fuseable link okay. I get 12v at the small wire under hood.

I do not get spark, or fuel.

If I jump the fuel pump relay I can make the pump run.

I have bypassed the OBC, by putting the two solid green wires together. Is this the correct way? Is there anything else I need to do to bypass this?

I do get a check engine light on the dash.

I have verified my grounds are correct. Body to oil pan, one on the wire harness (on the diag connector) and little one on the fuel rail to engine lift point.

Is there anything else I can check before shelling out money for another computer?

Thanks.
Jay

[M3PO]

No spark and no fuel is exactly what happened to me when my DME had EWS.

[dunebuggyjay]

No spark and no fuel is exactly what happened to me when my DME had EWS.

Did it still crank with the DME having EWS?

I have another 413 red label coming tomorrow. Hoping this is it.

I saw the engine run (although it was bad with all the vacuum leaks and old gas, but it at least ran) before I pulled it out of the car.....but I did not use the DME from that car...


I bought a red label 413. Hmm.

I also noticed my crank sensor (converted to obd1 by previous owner) shows nothing when i check its ohms.

I have also ordered a new one. Wondering how this got bad from just sitting in my garage for a year though.

Thats probably my biggest issue. But i thought the DME would at least tell the fuel pump to prime. (which it does NOT do) even with a bad crank sensor.

Maybe a combo of bad dme, and crank sensor. Im getting close....i can taste it!

Jay

[M3PO]

Yes, it would crank with EWS. But the DME would not run the fuel pump, injectors, or trigger the coils. But none of the 413 Red DMEs have EWS to my knowledge.

I think the crank sensor is basically the only sensor that it won't run without. If there is no resistance across the crank sensor, that sounds like your issue.

Did it still crank with the DME having EWS?

I have another 413 red label coming tomorrow. Hoping this is it.

I saw the engine run (although it was bad with all the vacuum leaks and old gas, but it at least ran) before I pulled it out of the car.....but I did not use the DME from that car...


I bought a red label 413. Hmm.

I also noticed my crank sensor (converted to obd1 by previous owner) shows nothing when i check its ohms.

I have also ordered a new one. Wondering how this got bad from just sitting in my garage for a year though.

Thats probably my biggest issue. But i thought the DME would at least tell the fuel pump to prime. (which it does NOT do) even with a bad crank sensor.

Maybe a combo of bad dme, and crank sensor. Im getting close....i can taste it!

Jay

[CENTURION]

is it grounded from block to chassis?

main relay?
fuel relay?

[dahows]

I was thinking main relay as well; have you confirmed the main relay is functioning?

[dunebuggyjay]

It was definitely the crank sensor.

Got it started. Now working on turbo downpipe.

Thanks for all the help guys.
Jay