3.0 D-Jet to 3.5 conversion

Sven

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I have some answers. The valve cover is needed because the bolt hole in the upper timing cover is in a different position. The motronic distributor, and the way it is mounted, is completely different from the original (hence the need for a different upper timing cover, and valve cover). The fuel pump option that I used is a two pump set up. One pre-pump in the tank (part of a 320i pump/sender unit that fits in the existing tank hole) and a separate main pump. The 320i sender unit is about 10 cm too short, so I had to lengthen the pump to reach the bottom of the tank. The sender will read empty with still 3-4 gal. of fuel remaining. I believe you need just 4 sensors. O2, coolant temp, manifold air temp, and timing (VR sensor mounted on lower timing cover, reading the toothed harmonic balancer wheel).

Oh - forgot the throttle position sensor. I think the D-Jet sensor is either open or closed. The motronic needs a variable reading from 0-100%
 

chicane

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I have some answers. The valve cover is needed because the bolt hole in the upper timing cover is in a different position. The motronic distributor, and the way it is mounted, is completely different from the original (hence the need for a different upper timing cover, and valve cover). The fuel pump option that I used is a two pump set up. One pre-pump in the tank (part of a 320i pump/sender unit that fits in the existing tank hole) and a separate main pump. The 320i sender unit is about 10 cm too short, so I had to lengthen the pump to reach the bottom of the tank. The sender will read empty with still 3-4 gal. of fuel remaining. I believe you need just 4 sensors. O2, coolant temp, manifold air temp, and timing (VR sensor mounted on lower timing cover, reading the toothed harmonic balancer wheel).

Oh - forgot the throttle position sensor. I think the D-Jet sensor is either open or closed. The motronic needs a variable reading from 0-100%


That sees a bit complicated if I cannot use the OEM electric fuel pump can I simply replace it with and aftermarket pump. I do not which to use an in tank setup. Also are there any wireing diagrams on how to hook up the Motronic 1.3 system to the existing OEM system?
 

x_atlas0

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I'm looking at this again and I had a few questions:
1. What sensors am I looking for with this harness?
2. I am assuming that the ECU must be from a manual car? (do you have the Bosch part number?)
5. The fuel pump for these cars will not work it is an in-tank pump
8. What do I do with the old distributor? Remove it and try to find some cover plate?
9. What do I need this valve cover?

1. Main sensors:
crank position sensor
coolant sensor
timing sensor (6th spark plug wire will have an inductive pickup on it, that is what I am talking about)
O2 sensor
AFM
throttle position sensor
Idle Control Valve

2. Nope, you can use an auto DME, but you will also have to use the auto throttle position sensor. The manual/auto switches are different. I do not know if you can sub in a manual TPS in an auto DME. I pulled the whole rig from a 91 735 auto.

5. There are two pumps, a pre-pump, in the tank, and the main pump, outside the tank, which is placed next to the primary fuel filter. The outside pump does most of the work, this is the pump I am talking about. The Motronic fuel pressure is ~50 psi, with a fuel pressure regulator on the rail itself.

8. Using the upper timing cover replaces the original distributor with the point-less Motronic distributor, which is just a cap and rotor. You may or may not need to remove the dizzy driving nut at the end of the cam. It's been a few years and I can't recall at the moment.

9. The valve cover ties in with the AFM and the upper timing cover. The upper timing cover's valve cover volt is off-center in the Motronic systems, but on-center in the older systems. (or was it the other way around... either way, the point is they are different.) Therefore, you cannot use the old cover with the new system.
 

chicane

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1. Main sensors:
crank position sensor
coolant sensor
timing sensor (6th spark plug wire will have an inductive pickup on it, that is what I am talking about)
O2 sensor
AFM
throttle position sensor
Idle Control Valve

2. Nope, you can use an auto DME, but you will also have to use the auto throttle position sensor. The manual/auto switches are different. I do not know if you can sub in a manual TPS in an auto DME. I pulled the whole rig from a 91 735 auto.

5. There are two pumps, a pre-pump, in the tank, and the main pump, outside the tank, which is placed next to the primary fuel filter. The outside pump does most of the work, this is the pump I am talking about. The Motronic fuel pressure is ~50 psi, with a fuel pressure regulator on the rail itself.

8. Using the upper timing cover replaces the original distributor with the point-less Motronic distributor, which is just a cap and rotor. You may or may not need to remove the dizzy driving nut at the end of the cam. It's been a few years and I can't recall at the moment.

9. The valve cover ties in with the AFM and the upper timing cover. The upper timing cover's valve cover volt is off-center in the Motronic systems, but on-center in the older systems. (or was it the other way around... either way, the point is they are different.) Therefore, you cannot use the old cover with the new system.

Do you happen to have pics also? I bought the parts so I am ready to roll on this.
 

Stefan

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D-jet

Reading all threads according to D-jet in this I assumed that would be my worst nightmare when starting up my csi after almost 30 year at sleeping.

Well, since starting the engine, the D-(dinosouar)Jet was the function with 100% reliable.

The car is running like a swiss clock.....

All of the car runs like a swiss clock, and I'm really surprised. My (recently awaken) E9 was my best friend this summer......

Cheers !
 

x_atlas0

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Reading all threads according to D-jet in this I assumed that would be my worst nightmare when starting up my csi after almost 30 year at sleeping.

Well, since starting the engine, the D-(dinosouar)Jet was the function with 100% reliable.

The car is running like a swiss clock.....

All of the car runs like a swiss clock, and I'm really surprised. My (recently awaken) E9 was my best friend this summer......

Cheers !

Lucky! Mine's been more like a Chinese knock-off of a swiss clock, but I'd say that is more due to my lack of involvement with it for the last year or two.
 

chicane

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OK, I have most everything that I need now but I have a few more questions.
On top of everything listed:

1. Motronic 1.3 harness
2. Motronic 1.3 DME
3. All sensors attached to the engine harness.
4. Motronic intake manifold, the B35
5. Motronic fuel rail, injectors, regulator
6. 2002tii brake booster
7. Upper timing cover from a B35
8. Motronic ignition system (cap, rotor, plug wires, possibly coil)
9. B35 valve cover
10. B35 throttle and throttle position sensor
11. O2 sensor bungs welded into downpipes
12. Motronic 1.3 harmonic balancer
13. Motronic 1.3 crank position sensor bracket
14. Motronic 1.3 coolant temp sensor

But do I also need the following:

1. Idle Control Valve
2. Distributor Jack Shaft
3. Air Flow meter
4. Throttle linkage
5. AFM Bellows

Also, did you just splice the engine harness into your E9 harness or did you use a different wiring harness for your car?
 

x_atlas0

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The throttle linkage will have to be somewhat customized, as the original carb linkage is based on "pushing" and the current linkages are based on "pulling". I was able to make a perfectly serviceable unit using some generic cable and the carb linkage L-bracket.

You will need the AFM and the ICV, and the rest of the intake plubming. I am not clear what you mean by the dizzy jack shaft.

In terms of the harness, the engine harness is almost completely seperate from the chassis harness. The only major connecting points are power, ground, and ignition. Everything else is effectively self-contained. It is one of the nice things about older FI systems like Motronic.
 

chicane

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The throttle linkage will have to be somewhat customized, as the original carb linkage is based on "pushing" and the current linkages are based on "pulling". I was able to make a perfectly serviceable unit using some generic cable and the carb linkage L-bracket.

You will need the AFM and the ICV, and the rest of the intake plubming. I am not clear what you mean by the dizzy jack shaft.

In terms of the harness, the engine harness is almost completely seperate from the chassis harness. The only major connecting points are power, ground, and ignition. Everything else is effectively self-contained. It is one of the nice things about older FI systems like Motronic.

I have the CSi so I don't have carb linkage does that make a difference?
 

x_atlas0

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I have the CSi so I don't have carb linkage does that make a difference?

I'm not sure. I have yet to see a CSi linkage, but I imagine it works along similar lines as the CS linkage, due to the way the pedals are set up. You may be able to re-use it, though, assuming it doesn't "pull" from the get-go.
 
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