I'd change it no matter if it has never been while under your watch. Not sure what to say about removal beyond spraying penetrant all over it, and some vice-grips. Hate to say it, but some unexpected disassembly may be required to make room for tools. Maybe someone has a trick for us all.

 

Yea, i have no idea, i had ago before work, but failed hard. I finish work in 3 hours to try again and the car needs to be driving in 5 hours. Its pissing down with rain and the car is stuck on the front lawn. Happy days lol!

 

Replaced the CPS today. It started a few times fine. Then it became very hard to start. Had to wind it for abit with the accel pedal down to get it started. Where else should i look?

 

Dirty injectors? Fuel filter?

 

Injectors were replaced with recos from a newer model (M20 upgrade ones) along with fuel filter a few months ago. FPR was replaced with a second hand one so unknown. Fuel pump hasnt been touch. Nothing in the sparking side of things has been touched since i bought the car. All this stuff is on a list to replace, but its below the more serious stuff.

 

If the CPS is new and the connections good it seems to lack fuel. Vac leak or fuel supply problem.

 

Ok, so its back to no spark or injector pulse again. This is with a new CPS. Does this mean its down to the DME and/or the DME relay? As im still waiting (yes after paying $50 for express postage 2weeks ago from pelican parts) for the new relay to arrive.

So is there a way to jumper the relay to eliminate that from the list of possibilities? Or should i look at other things.
The car had been driven all week, with multiple starts. This morning it started 3 times and drove a few meters and all was well. Just went to move it for the last time before painting it and it wont start.

 

Further update: It only happens after rain. Depending how heavy it is determines how many days it wont start. Yesterday i washed the car very quickly. It wouldnt start for atleast 20mins. I barely got any water on the front of the car. Proberly enough for it to run down into the wiper arm area.

Is this a common issue?

 

Don't even know what year or model lol.

 

My bad, thought i put it up in the first post.

1989 E34 525I M20B25

 

2 things you can try are:

Open the sun roof & gently poor water in the channels to see if the water comes out behind the front wheel & infront of the rear wheel on both sides, the rubber hose that allows water to exit if the sun roof if the seal isnt sealing may be blocked or even perished.
Try & start it.
If its ok then:

Pour water on the windscreen again then open the bonnet & then the box with your ECU & see if theres water in it. If there is then the hose that connects from the cooling fan to the E box is out of place or perished.

 

Ill test the sunroof one, how will this effect it?
No water in the DME box area, iv even ripped it out to see if any water was in it. So im eliminating this.
Its something new, its been through rain alot, but only since the exhaust was done a few weeks ago, its started.

 

If the sunroof is blocked then the water will run down the pillars internally it doesnt have to be that much, there are wires running up those pillers connected to the ignition. I'd rule out the exhaust work cause the only thing they can really damage is the 02 sensor which would only effect the car when it gets past about 1/4 on the temp gauge & when running.

may not be your problem, its just strange it happens when you hose the car down or it rains.

 

Yea, its doing my head in. Ill be doing some more tests in the morning. Ill start the car, then turn it off, hose it down, try and start it. Then if it doesnt start, then mess around with **** till i find what the water is doing.
By hosing the car i mean hose sections and try and start and then hose another and so on. Its doing my head it as i really only need to drive when it rains lol.

 

Dam Queensland weather, but yeah testing it in sections would be the best way to troubleshoot.

 

From what I've learned here, definitely can't go wrong replacing the DME relay no matter what. It has cycled probably most or all of it's expected service life cycles in its years. Then, I'd try the DME after that. Again, as I was taught here, not much harm in having a back-up, even if the original issue is unsuccessfully fixed. Following that, I'd check harness end to end connection (DME connector to CPS connector) continuity to get that question entirely out of the way.

 

From yesterdays test, i cant see where the water is causing a problem. Hell it even started whilst wet yesterday. Today it wouldnt start tho. It did not rain last night and its a nice clear hot day and has been for 4 hours now. No start again. The DME relay is working, i can feel it clicking when i turn the key on. Yet, after 3 weeks of waiting for an order from pelican parts (with express international posting i might add) i still have not got my new relay. I cant even find another DME for sale here either.

 

Another update to keep this thread as informative as possible.
Put in another DME/ECU today. However since it kept flashing my check engine light i put my tune chip into the other DME. So original tune, different DME box.
It looks like its going to be raining soon, so heres hoping the problem is solved.

 

Well it rained whilst at work for about 30mins pretty lightly. Car doesn't start again. Been trying to start it for an hour with no luck. It has got to be some wiring somewhere that when it gets wet it stops the injector pulse and spark..

 

Captains log #5465454
I removed the DME, relays and whatever other computer was there today. Put them up on high ground and tipped water all over the wiper arm area on both sides, the sunroof, the boot and even on some main wiring in the engine bay. The piece of **** still starts. The DME or the box didnt have water in it last night. This is doing my head in. I cant seem to replicate the no starting issue.
Also should my relays be wired like this?

 

Another post.. Yay...
So iv ruled out anything in the DME box, including all the wiring in there.
The DME is complete sealed. Silicon over all the edges. All wiring in that box has been taped up then gone over with brush on electrical tape. The lid is seated and screwed down tight.
Started up fine (its been raining the entire time iv been working on it). Started up fine, then i turned it off and packed up my tools and closed the hood. When to start it 5mins later and it wouldnt start. It was trying to catch but i needed to keep it turning with my foot flat to the floor (WOT) to get it to kick over.
If theres anyone still reading this, what are your thoughts. Im losing my **** over this.

 

Here's a clue, if you want to disable the ignition system you have to remove the DME main relay. Thats that white one in your E Box.

 

Its working tho. Every time it doesnt start, it clicks when i turn the ignition on. Also waiting for a new one to come from pelican parts to be on the safe side (its been a month now.. Even paid the expensive express postage).

However, its only after it rains the water does not get in that box. If i was to submerge the engine bay, the only way water would get in is through the drain hole at the bottom and the rubber boot going to the cabin. I made sure today every wire was sealed, the ECU completely sealed and the black box sealed.

 

Is it definetly the DME relay you hear click or the fuel pump relay or 02 sensor heater relay? Also what did that relay cost you including postage?

 

Its defiantly the one i hear and feel. But i wont know til the new one shows up and i swap it. New fuel pump is on its way too. Its the last thing in the fuel side of things i have no replaced since i bought the car months ago.
I ordered a CPS and relay from pelican. Relay was $20USD, CPS is $40USD and express postage was $50USD.. 1 month later im still waiting for these parts.. I ordered a CPS locally for $130AUD because i need to fix the car. I also ordered another CPS which is the wrong one for me.. Iv even changed the DME ($180AUD) plus a 2hour drive each way.

Theres no concrete information on any other relays working in place of the BMW one.. Just one other brand which comes up when searching for the original part number. Nothing new in Australia either.