1.3 Motronic Up-Grade & 2.7i How To

[hotballs]

Grab the thermostat housing, it should have all the sensors you need. You also need the crank position sensor on the front side of the engine next to the toothed harmonic balancer aka crank pulley. You need the throttle body with the TPS sensor attached to that as well. You also need the 8th plug wire or what ever it's called that pulses on one of the other plug wires. You'll notice there is another plug coming off the spark plug wires which doesn't go to the coil or a spark plug. That wire.

I think those are all the sensors. You could of course just read this thread from front to back, but it's so long I doubt anyone does that anymore.

[call me jack]

Can some body give me a list of exactly all the sensors i'll need?

i'm trying to put things together, so i need to know what to look for in my parts cars...

[SoopaGhetto]

Are there any differences between the e and i temp sensors? I know the 'i' thermostat housing only has two sensors and the 'e' thermostat housing has 3 but im referring to the actual functionality of the primary sensors needed for 1.0/1.3 operation (excluding the thermal time). im thinking the dme/cluster coolant temp sensors are the same...

Also, when pulling the harness of an 87 325i, i noticed that the oil pressure sensor uses a fuel injector looking clip but only one wire. the 86 es i have only has a single wire spade type connector. would that oil pressure sensor fit in the same place or would it be better to just splice that connector?

there was a 90 525i which im pretty sure utilizes the m20. would anyone happen to know what dme it may have? i think i read 340? should be comparable to 173 and be better than 153 right?

currently im attempting to do just the 'e' to 'i' 1.1/1.3 conversion with just the 'i' intake/tb and afm. im hoping this would give my eta a nice pick-me-up due to the the better engine mapping

[call me jack]

I'll sell you the complete conversion including most gaskets, ecu etc. for $350+ shipping, PM me if you're interested.

I need to figure out how to PM, but it's on the way!

[884door]

thanks alex. another question though

how much should we be looking to spend on this conversion? and any tips on where we might be able to find the parts, other than craigs list?

I'll sell you the complete conversion including most gaskets, ecu etc. for $350+ shipping, PM me if you're interested.

[acolella76]

lucky for me, the previous owner totally rebuild this slow ass 325e engine lol


so, where is the connector i'm supposed so splice/change to the round c101 plug? I'm normally not this much of a noob, i swear

[lateracer]

The for sale sections here and on some of the other forums will have most of what you're looking for.

Prices vary depending on how much you find grouped together really. I scored an intake with fuel pressure regulator and throttle body for about $100, head for $150 shipped, harness for $60 and so on. In the end, I think the total cost for an i head upgrade would have been around $500 once I included things like gaskets, timing belt and other things. I say "would have been" b/c while I was piecing the last few things together, I found an i motor (b25) for $200 on CL.

If you're looking to upgrade a seta with a motronic 1.3 system in place, I think you can get away a lot cheaper than I did. Otherwise, just buying a used i motor/harness/DME is likely a better choice. Being able to rebuild the motor from top to bottom the way you want it and get to other maintenance things like the oil pan gasket, rear main seal and hard to reach hoses will result in something you can just drop in and forget about for a while when you make the swap...and after a job like this, chances are you'll want to drive instead of turning wrenches for a while.

[call me jack]

thanks alex. another question though

how much should we be looking to spend on this conversion? and any tips on where we might be able to find the parts, other than craigs list?

[acolella76]

Can some body clairify why they mean when when they say "Dual exhaust"

I have a feeling they're refering to the manifold, so with that said, i could just use a header, right?

The 318's and 325e's headers come together just before the cat converter, and from then on the exhaust is 1 pipe, but on the 325i the exhaust is 2 pipes the whole way.

[call me jack]

Dual exhaust.

Can some body clairify why they mean when when they say "Dual exhaust"

I have a feeling they're refering to the manifold, so with that said, i could just use a header, right?

[acolella76]

sorry if i'm beating a dead horse, but does anyone have a DIY for just replacing the sensors and electrical nonsense from an 85? I'm going to use my E head, I cams and springs, and headers, and swap everything else over i need to run the 173 ecu. I just don't really know anything when it comes to the electrical part.

Also, would it be fine to just cut the sensors and leave them in the bellhousing so i don't have 2 holes?

[hurttech]

There is a 3 wire plug on the interior of your car that used to connect to the eta harness right next to the DME. It has black/yellow/green wires. I believe the black wire is for the tach.

I tried connecting the engine speed output from the 1.3 dme to the black wire on that connector and got nothing. Is there another wire that needs to be connected in order for the tach to read the signal?

[hotballs]

There is a 3 wire plug on the interior of your car that used to connect to the eta harness right next to the DME. It has black/yellow/green wires. I believe the black wire is for the tach.

[hurttech]

I'm going from an '85 E and using an '89 i top end and engine harness, where would the tachometer get it's signal from?

[Imagine_M]

I guess what I meant to say is that it doesn't say anything about having to rewire and as detailed as it is I'm sure it would say if needed...