Announcement

**pazi88** · 10-21-2016, 02:06 AM

I still suspect wiring issue. Disconnect the DME and turn on ignition without that. Does the fuel pump still run?

**Klug** · 10-21-2016, 08:03 AM

Originally posted by pazi88 View Post

I still suspect wiring issue. Disconnect the DME and turn on ignition without that. Does the fuel pump still run?

No, pump does not run when the DME is disconnected, I think due to the fact that the fuel pump relay is contained within the engine harness. Therefore there is nothing telling it to power on. I have Pin 13 x20/Pin 13 c101

Sent from my Nexus 6P using Tapatalk

**Klug** · 10-23-2016, 03:24 PM

I just keep digging into this and still not figuring out what I need to do.

Tested fuel pressure- when pump is running I am at 55PSI (3.8BAR), when it stops I sit at 45PSI (3.3BAR) and it slowly decreases over a few hours- normal, so I am ruling out a bad FPR with the ODB2 running losses valve. Re-ran (again) new fuel lines and clamps- no leaks. FPR vac line is running to the M50 intake port near the firewall. Replaced the fuel pump to a brand new bosch unit I had for my other e30.

Fuel Tank Pressure Sensor- Discovered that the DME looks at the stock e36 FTPS which is tied into the crank position sensor and throttle position sensor. I do not have this hooked up. While I found a DIY to pass CA Bar, of installing this sensor on the evap tank- I don't live in CA nor do I care about installing this. Odd- as I can't find any info (trust me I have about 30 tabs open) of what to do to actually delete this. My guess is that the DME doesn't know the fuel pressure of the tank- so it will continually run.

Basically the fuel pump is running like this- key ON (no crank) pump kicks on and builds up pressure for about 15 seconds. Turns off, then over the next minute, will kick on for a second then off for about 20-30 seconds, then maybe turn back on for 10-15 seconds, off for another 20-30 seconds then it kicks on and just stays on.....

Charcoal Canister I have the vented line running to it and the exit line releasing to the atmosphere. I read on one thread that people have hooked up the out line to the FPR...but that doesn't make any sense. I tried hooking it up to the intake port near the ICV port and that doesn't change anything (which is now capped)

Reading more into it- I do not have anything wired from my X6031. Anything I need to do to this? My tune is the Kassel MS41.1 which deletes the EWS, Muffler fap, SAP and post O2's.

Help! :)

**2mAn** · 10-23-2016, 05:19 PM

I want to convert to ODB2

**pazi88** · 10-23-2016, 11:16 PM

Ok then it sounds that you may have corrupted tune in you ECU. Try with non-flashed ECU.

**328ijunkie** · 10-24-2016, 06:02 AM

Fuel pump should not run constant like that. ECU fires fuel pump when it deems fit. ECU doesnt care about tank pressure sensor or anything like that and it has no fuel pressure feedback. It basically primes every few key ons (without start) and then when cranking/running will fire constantly when it sees a good crank signal.
Sounds like a bad tune/DME....
:|

**AllydNYC** · 10-24-2016, 08:38 AM

I don't know if this would help, it's pretty basic stuff I'm writing but I had this exact same priming problem last week along with my engine not cranking or anything. It was my first start. I had a harness made for me that was labeled and I bought a tune with an ECU, so I felt it was me hooking up something wrong that wouldn't get the engine to start. It wouldn't do anything, no sounds other than the relays clicking on and the constant priming of the fuel pump.

I did a few things to troubleshoot the engine not doing anything when the key was turned; checked grounds (fine), hit the starter if anything was stuck (not related to your problem), and then I unplugged my ECU, removed it from the bracket, blew on all the connections and reconnected it. I didn't put it back in the ECU bracket because it was causing strain on the cables. I didn't realize until later that you need to move the ECU bracket closer to the firewall to increase the slack of the ECU cables. I'm not sure if you got a bracket for your ECU yet. I had one already since mine is an 318.

Blowing on the ECU pins and plug, reseating the ECU plug and giving the cables less strain stopped it from constantly priming and started my M52 (OBD2). So sounds like something with your ECU. Try cleaning the connections and reseating the connection. If that doesn't work it is probably bad.

**Klug** · 10-24-2016, 10:33 AM

Awesome- thanks 328ijunkie and AydNYC for that input.

I'm going to go through everything today...again. Ripped out the whole harness last night and have it all laid out on my garage floor. Going to test every single connection before connecting it to the DME and clean every connection. Eventually, once I get everything hooked back up again...i'm going to see if I am seeing similar issues. If the pump still acts up the same- I am going to send this ECU back down to Kassel and get it reflashed. If they determine the flash is fine- 328iJunkie, you'll be receiving a PM looking to order a new MS41.1 tune from me. I'm tired of wasting hours and hours on figuring out what is up with this thing.

I also have one other question I noticed when I was testing the sensor pin outs yesterday. The 15A fuseable link lead from the battery- what wire from the s52 harness gets connected to this? Main/Fuel relay? or is it the "K6326 terminal 15 unloader relay" that is next to the DME? I originally had the unloader relay on this separate terminal- not sure if this might be an issue....

**328ijunkie** · 10-24-2016, 10:46 AM

Originally posted by Klug View Post

Awesome- thanks 328ijunkie and AydNYC for that input.

I'm going to go through everything today...again. Ripped out the whole harness last night and have it all laid out on my garage floor. Going to test every single connection before connecting it to the DME and clean every connection. Eventually, once I get everything hooked back up again...i'm going to see if I am seeing similar issues. If the pump still acts up the same- I am going to send this ECU back down to Kassel and get it reflashed. If they determine the flash is fine- 328iJunkie, you'll be receiving a PM looking to order a new MS41.1 tune from me. I'm tired of wasting hours and hours on figuring out what is up with this thing.

I also have one other question I noticed when I was testing the sensor pin outs yesterday. The 15A fuseable link lead from the battery- what wire from the s52 harness gets connected to this? Main/Fuel relay? or is it the "K6326 terminal 15 unloader relay" that is next to the DME? I originally had the unloader relay on this separate terminal- not sure if this might be an issue....

Should be 1 main power feed for entire harness... Not sure how kassel does theirs. Sounds complicated :dunno

**Klug** · 10-30-2016, 10:56 AM

Thanks for all the input guys, finally figured it out! Blame the harness adapter! Somehow had the C101 Pin #12 CEL light hopping on the switched power Pin #8. Which apparently just freaked out the e30 side into running the fuel pump non stop.

The only issue I currently have is the M50 Oil Level Sensor, have heard mixed reviews of which pin is actually GROUND. The e30 ETK states that it is Pin 2, while getting a whole mix of different sources telling me its 1, 2 and 3. Currently the pan is full of oil, I have ground contact at PIN 1 and PIN 2, nothing on 3- but getting en "engine oil" alert on the e30. Tried a bunch of combos but still can't get the light to go off. Swapped pins 1/3, still kept the OLS light on. Went to my other e30, get the same readings- 1/2 are grounded on a full pan, but still get no light. I don't know, its the least of my worries currently.

End all be all, I've noticed that you can't trust a single harness diagram out there, since it seems that everyone is totally different on the X20 side. It gets confusing very quick. Best thing is to lay out the whole harness and pin by pin figure out what actually you have going on. Plus it gives you peace of mind of what is actually going on with the DME. Plus your able to delete a whole bunch of AWS, ABS, EGR and EWS wiring that was unnecessary from the harness. I also ended up wiring the C101 directly to the s52 harness- didn't use a harness adapter to cut down on wiring and other issues that can come up. So one connection from the s52 harness to the e30 body over C101... now it looks like the engine was made to fit an e30!

Below is my spreadsheet that I used- maybe it'll help someone out in the future. Thanks for everyone's input!

X20 was from a '98 E36 M3 S52 Auto
C101 was from my '92 E30 Vert Auto

**328ijunkie** · 10-31-2016, 07:39 AM

Why did you remove VSS?

**Klug** · 10-31-2016, 09:33 AM

Originally posted by 328ijunkie View Post

Why did you remove VSS?

That was VSS Out (From e30 cluster) and couldn't figure out exactly where that would have went to on the MS41.1 side. Does it go to the diagnosis connector?

I have VSS hooked up from Pin #20 DME> Pin #9 e30- just not the other way around. From what I found, I didn't think the DME needed the speed input...correct me if I am wrong!

Edit: Now that I think of it, the speed is calculated by the diff correct? Which would be an output on the body side

**Klug** · 11-01-2016, 04:17 PM

Anyway, did some research- hooked up that ABS X6000 #15 (X20 #9) to the C101 #14 after further research.

And learned that the speed is determined by one of the ABS sensors, not so much the diff...or in correlation with each other...whatever ;)

Updated my diagram above for future use.

Announcement

Opposite day in ODB2 S52 land- Fuel Pump just won't stop pumping

Opposite day in ODB2 S52 land- Fuel Pump just won't stop pumping

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment