Car has many issues

[Boise30]

I just joined the forum. Did a quick intro and found my way here to see if someone can help me understand my car a little better. I have had to replace a lot since buying it a few months ago including fuel pumps, FPR, Windshield, Driveline and a few other smaller things. Lately, the car seems to cut power from 2-2.5k rpm. I have read a lot of threads about these issues and haven't found a specific fix to this, but it got me thinking about what MAY be my issue.

The ad, when I bought the car, called it an "i", but I realized it wasn't and bought it anyway. They had paperwork from back East for the purchase of a 325i motor, but it was vague with details and the company doesn't exist anymore. I figured they were mistaken and it was just an e motor and called it a day. That was until the other day when I was trying to figure out what I had and saw the "885" casting through the intake. Well my ECU ends in 027, and the engine wiring is still the e wiring, as it has the two sensors mounted on the bellhousing, rather than the single sensor on the front of the engine. HOWEVER, that sensor IS on the front of my engine, as is the toothed wheel it reads, but it isn't plugged in, nor is there a place to plug it in. Car runs decently with this setup but I doubt it is "right". Cluster is the "e" cluster as well. I should also add, the valve cover is the e style cover with the BMW logo, not BMW spelled out horizontally.

My question is:

Will one of these still run with the old wiring and an "i" motor as described? I want to know if i can find a new computer and harness as well as other necessary items and make it right.

Any advice or opinions would be greatly appreciated

[reelizmpro]

It's difficult to figure out what exactly has been done without seeing the car or having detailed pics. Sounds like an ETA car with what may be a 325i engine (ETA valve cover though) in it running on basic motronic. If this is the case, then you can convert to Motronic 1.1/1.3..no problem. It would be easier if the car is an 86-on model. You'd have to convert to C101 fuse box connector if it's an 84-85 car.

[Boise30]

If it would help I could try to get some pictures on my lunch today. May be hard to get casting marks off the head, but I can get whatever I think would be useful. It gets frustrating buying a car that is such a basketcase and not knowing much about it, but I feel like if anyone would be able to help, it's this forum. Thanks for the reply, btw!

[101]

We can help!

It sounds like you've either got an eta motor with an 885 ("I") head, or you indeed have a compete "I" motor that's running the older eta Motronic 1.0 engine management system. Casting numbers off the block and intake manifold as well as pictures will let us know for sure.

Does your thermostat housing have two sensors or four? That's the other true mark of the "I' vs. eta engines. The "I" has only two.

With regards to the front reference sensor and toothed wheel ... eta engines also have one of those - although it is mounted in a different spot on the timing belt cover. However, on the eta that front sensor is not used by the Motronic 1.0 engine computer. It only runs to the diagnostic connector and nowhere else. Your car would run just fine without it as it was only ever used when a BMW diagnostic machine was hooked up to that port. If you have the "I" reference sensor instead - then there's going to be no place to plug it into the eta engine harness.

[Boise30]

Here's a shot of my ECU



Above no. 2 cylinder



Shot of the fuse box side



Overall shot of the engine



Front of the engine. You can see the bracket for the diagnostic sensor, and also the sensor running through that plastic thing to the other side of the engine. I have never been able to find a place to plug this in, and if I understand it right, it shouldn't run without it.



These are just some pics I had on my phone. I'll still try to get some more.

[ST1G]

Looks to me like an Eta motor. It's an eta ECU, an Eta ICV, and eta valve cover.

You live in Twin Falls?

[estoguy]

I concur on the Eta.

[Boise30]

One question on that though: Why would it have that pulse sensor installed but not used? Assuming you guys are correct (which I don't doubt at all), is this a decent motor, or should I start looking for something a little better? I bought the car to do a little racing on weekends and as a daily driver. Nothing crazy, just maybe local hillclimbs and such.

And no, I live in Meridian. I did buy the car in Twin though.

[DesktopDave]

The front sensor was for the GT1 diagnostics computer. It can be disconnected as it only runs to the diagnostic plug.

The 027, low RPM tach and intake make it an eta...M20B27. There is a slender chance you might have some sort of a mongrel there. It's pretty easy to swap B25 parts onto a B27, and with some care you can come out way ahead, but I don't see why some confused soul couldn't downgrade to save a little cash and keep the car running. You might have a VIN stamped on the engine casting - just check it at BMWarchive. It's on the rear left, by the starter. You'll need to brush off the rust and gunk first, I'd bet.

Maybe they were talking about an '88 "super" eta longblock? The later etas all used the 885 head casting AFAIK. it's the same casting as the M20B25 but with an B27 cam and valve springs. Here's a spotter's guide. The super has a lot of differences. The super manifold is unique...it runs an updated version of Motronic...no cold start injector...etc..

As for the 2K flat spot, I'd check the resistance on the AFM wiper to see if it's in spec...and maybe the temperature sensors too. They don't last forever.

[ST1G]

One question on that though: Why would it have that pulse sensor installed but not used? Assuming you guys are correct (which I don't doubt at all), is this a decent motor, or should I start looking for something a little better? I bought the car to do a little racing on weekends and as a daily driver. Nothing crazy, just maybe local hillclimbs and such.

And no, I live in Meridian. I did buy the car in Twin though.

Oaky, I live at Cloverdale and Ustick. If you'd like to come over we can take a look at it. Just by driving it I can tell you if it's an eta or a 2.5.

Keep in mind Daily driving and hill climb are usually mutually exclusive.


I'll shoot you a message in FB and we can work out a time to meet up.

[Boise30]

There's the sensor that is for diagnostics (I guess) and the one behind the belt on the other side. In the last pic, the clip for the diag sensor is on the bottom. on the top is the other sensor... i'll get a better pic tonight.

ST1G:

I realize that, to clarify, its a DD now, with the intention of doing like the Bogus and freezeout hillclimbs one day. I have other vehicles for DDs but they aren't very good on gas and one isn't trustworthy atm.

I grew up between ustick and Fairview off five mile, and just moved from McMillan and chinden out to cherry and linder. I'm sure I've seen you around at some point. My other DD is a 1965 F100, white with "infidel" on the front window.

[Boise30]

Here's a shot of that sensor plug and the wiring behind it. Again, it ALSO has the diagnostic plug on the driver's side. I got the casting number off the block, but it's just the eight digit number, not sure if that will give any useful info or not...