TECHNICAL HELP NEEDED

[Carlitto76]

Hi guys
I am new here and would firstly want to apologize for starting a topic that someone might have sent previously, but after a very long search I could not link any topic to my actual problem.

Anyway I have an e 30 323i body that I have fitted a 325i motor in running on a 320i Baur harness and an ECU to compliment. I am mentioning Baur system because it only has a single tall time delay fuel relay next to th airflow meter.
Initially the motor would crank but not run at all, the fuel pump would not pump either so I tried jumping the relay the pump would work the motor would crank as normal but still won't run because the injectors wouldn't pulse. Hence the injectors pulse through the ECU I figured a way to send signal to the ECU and jump the pump at once. I pulled a wire from the positive terminal of the coil to the green/violet wire on the FPR plug and connected the relay back.
The car starts but won't Rev up. I have changed the FP, FPR, FF, Injectors and recently checked and cleaned the GPS with no success. The only time the the motor tries to Rev up is when I help by hand to move the sweeper arm of the airflow meter.
I SERIOUSLY NEED HELP AND SORRY FOR A LENGHTY POST.

[Carlitto76]

In addition when I move the airflow sweeper arm by hand to Rev up the motor it sputters at high Revs and a gradual opening of the throttle picks up the revs but a sudden throttle would cause the motor to stall and want die.

[mark_i]

Hey carlitto.
Can you confirm that your set-up is using the two timing sensors on the gearbox bell housing.
These two sensors tell the ECU what are the engine revs and TDC.

[Carlitto76]

Hi Mark
I only have 1 pickup sensor situated at front( harmony wheel) and from what I found out is that it is used for testing of some sort and can comfirm that with my previous e30 it didn't matter where it was placed the moteo operated as normal

[Carlitto76]

What I also forgot to mention is the fact that it is a L Jetronic so I can't do fault code reading

[mark_i]

OK. Later today I'll go to my garage and collect the notes I made when I saw this problem . Update to follow

[Carlitto76]

I would really appreciate that and thanks in advance

[Brianmoooore]

If I understand this correctly, we have a 2.5 engine trying to run on 2.0 litre electronics, which is never going to be successful without a complete reprogram of the ECU.
The mixture is adequate for the car to idle, but the fuel rate isn't being increased fast enough when the throttle opens.

[mark_i]

Hi carlitto.
Reading through the idle issues I had with an L Jetronic in a 323i , I was lucky to have a second working system to compare.
The problem in the end was caused by corrosion inside the water heated idle valve.

[Carlitto76]

If I understand this correctly, we have a 2.5 engine trying to run on 2.0 litre electronics, which is never going to be successful without a complete reprogram of the ECU.
The mixture is adequate for the car to idle, but the fuel rate isn't being increased fast enough when the throttle opens.

HI Brian
Thank for your input, but I had this same set up and system in one of my 320i body saloon a few years ago and it worked perfectly fine without any issues. The reason why I took it out was because the body was too rusty and did not want to fiddle with that. Now I have it in a cabriolet and it gives me issues. What I realized between the two bodies is that here and there the color of some wiring are not the same and I doubt that wiring is the issue here otherwise the motor would have started. The fact that the FPR plug had no power makes me think that maybe the harness broke off somewhere over time, but will definitely look into reprogramming the ECU to support 325i if I find someone who can do it or get 325i harness with ECU since most of the guys here remove stock system, install dictator FMS to run multi valve 328i and Lexus v8 on e30.

[Carlitto76]

Hi carlitto.
Reading through the idle issues I had with an L Jetronic in a 323i , I was lucky to have a second working system to compare.
The problem in the end was caused by corrosion inside the water heated idle valve.

HI Mark
Are you referring to the airslide valve situated somewhere under the intake? If yuo are then I took it off years ago hence it was sticky inside and realized the harness I am using currently does not have loom/wires to support the 7th cold start injector situated on the right hand side of the intake which someone told me that the two work hand in hand.
I am now in possession of two airslide valve which couple of days ago was thinking of of one of the just to chech if it would make any difference.

[Carlitto76]

Hi Brian
just for interest sake,
Could it be that corroded spark plug leads do not give enough spark on high Revs to burn the fuel supplied at high RPM causing the engine to sputter or suffocate due to rich mixture(too much fuel supply)? The smell of the rich (improperly burnt) fuel makes ask this question and before I go out to buy any replacement leads is there away I could do a test on the current leads to check if they deliver the correct amount of spark (voltage)? If there is how do i do that?
Or could it be the two temp sensor on the thermostat housing brown for cold/hot(warm) start and blue am not sure (what's it for) that are sending false signal to the ecu, but if the brown one was too bad the the engine would not run isn't it? The temperature gauge works fine though. Thanks in advance

[mark_i]

Correct .the air slide valve. But I read your post again and there is more to your problem than just the idle.

The jetronic system is complicated and as you have noted , items such as the cold start injector can be the problem.
Can you confirm the combination of ECU and engine size.

[Carlitto76]

The ECU part number is 0280 001 309 fitted on a 320i manufactured between '84 to' 87 and the motor 2.5 sub assembly with 2.7 cylinder head. I am not sure if this is what you wanted me to confirm

[Brianmoooore]

Hi Brian
just for interest sake,
Could it be that corroded spark plug leads do not give enough spark on high Revs to burn the fuel supplied at high RPM causing the engine to sputter or suffocate due to rich mixture(too much fuel supply)? The smell of the rich (improperly burnt) fuel makes ask this question and before I go out to buy any replacement leads is there away I could do a test on the current leads to check if they deliver the correct amount of spark (voltage)? If there is how do i do that?
Or could it be the two temp sensor on the thermostat housing brown for cold/hot(warm) start and blue am not sure (what's it for) that are sending false signal to the ecu, but if the brown one was too bad the the engine would not run isn't it? The temperature gauge works fine though. Thanks in advance

Plug leads are proper copper wire with series resistors in the cap heads, not the 'burnt string' rubbish used by some other car makers, and are unlikely to be at fault, but they can be checked by comparing the resistance of all six leads, which should be near enough the same. Distributor cap and rotor arm are much more likely to fail.
Brown temp. sensor is solely for the temp. gauge, and, because of its low resistance range is unlikely to fail, unlike the blue one for the ECU, which isn't known for long term reliability. They fail open circuit though, which will have little effect on a cold engine, but make the mixture excessively rich as the engine warms up.
I still think your best option is to ditch this primitive electrics, and replace it with a Motronic set up, preferably 1.3, which works exactly the same as a modern engine, give or tale a sensor and feedback loop or two. Whatever you do, you'll never get this running better than a comparable engine on carbs.

[Carlitto76]

Thank you. I will search around for a complete moronic system and components

[Brianmoooore]

Parts from a facelift 320i or a 325i are the same, except for the AFM and the ECU, although the ECU differs only in the 'chip', so a 320i ECU can be used along with a mildly uprated aftermarket 'chip', such as those supplied by Speedtouch on here.

[Speedtouch]

A cheaper way to improve things would be to fit the 323i, rather than 320i, L-Jetronic ECU, as per this list:

https://www.e30zone.net/e30wiki/index.php?title=ECU

This should then give you ignition timing and air/fuel ratios closer to that required by the 325i engine.

[Carlitto76]

Hi guys
It's been a couple of days since I last posted anything, but it is with great excitement that I am posting today. After trying 2 ECU's today (from a 323i and 528i) and two sealed air flow meters (from 320i and 325i). I still could not resolve the issue and last night I was thinking to myself if the ECU and air flow meters do not work then I would resort changing the harness to motronic hence a friend of mine has 1 with the ECU, but finally my persistence paid off and I managed to resolve my issue without changing the harness. I must admit fault finding is a long, difficult and challenging process that requires a great amount of patience.

[minesapint]

So what was the fault?

[Carlitto76]

So what was the fault?

Hi
The fault was the starter wire (black/yellow) . The original wire seemed to have build up some carbon and did not turn the starter, so I laid a new wire from the ignition monkey puzzle to the starter liviving out the original wire. This turned the starter, but caused the fuel pump to run non stop when the ignition is on. The pump is supposed to switch on and run for a brief moment and then go off until you start cranking or the motor is on running mode only then must the pump supply fuel.i reckon there was some sort of miscommunication within the system (ECU, TPS & INJECTORS).
I am ecstatic and can finally move on to other things

[minesapint]

Glad you’ve got it sorted....or very nearly.
My understanding was the fuel pump only runs once the engine starts cranking.

[Carlitto76]

What I meant to say was that the fuel pump gets triggered once (brief moment) by the relay then only runs constantly when the engines is cranked or runs.

[Brianmoooore]

Hi
The fault was the starter wire (black/yellow) . The original wire seemed to have build up some carbon and did not turn the starter, so I laid a new wire from the ignition monkey puzzle to the starter liviving out the original wire. This turned the starter, but caused the fuel pump to run non stop when the ignition is on. The pump is supposed to switch on and run for a brief moment and then go off until you start cranking or the motor is on running mode only then must the pump supply fuel.i reckon there was some sort of miscommunication within the system (ECU, TPS & INJECTORS).
I am ecstatic and can finally move on to other things

I'm sorry, but this makes no sense at all, especially in reference to the original description of the fault! Whatever your fault was, the above is not relevant.

[Carlitto76]

Hi
The fault was the starter wire (black/yellow) . The original wire seemed to have build up some carbon and did not turn the starter, so I laid a new wire from the ignition monkey puzzle to the starter liviving out the original wire. This turned the starter, but caused the fuel pump to run non stop when the ignition is on. The pump is supposed to switch on and run for a brief moment and then go off until you start cranking or the motor is on running mode only then must the pump supply fuel.i reckon there was some sort of miscommunication within the system (ECU, TPS & INJECTORS).
I am ecstatic and can finally move on to other things

I'm sorry, but this makes no sense at all, especially in reference to the original description of the fault! Whatever your fault was, the above is not relevant.

I hear you. Maybe the manner at which I went on explaining or expressing myself isn't clear enough. Anyway what I did was join the old blck/yellow wire with the new one and the problem was solved. So I do not understand when you say my explanation does not make sense and it's irrelevant to the to the described fault.
Bare in mind that after I did all that I could such as laying new black/yellow wire (to be able turn the starter coz initially it wasn't), changing injectors, fuel pump and regulator and coil only then I posted my fault on the forum seeking technical help. So this means the car engine did start, run and idle, but would not Rev up either due to fuel starvation or flooding and with the specs of the ECU(from 320i) and the harness you said I would never resolve the issue and suggest that I tried ECU from 323 (which I did and did not work) or change to motronic( which was my last resort).
Before I posted this today I disconnected the new black/yellow wire living the original one the starter won't turn and I took it off and plugged the new wire the starter turns and the engine runs, but would not Rev up. I joined the two wires again everything is fine again? So what would you say is the problem?

[Carlitto76]

I really appreciate the few responses that I got from the forum as they saved me money and time trying to eliminate faults and what Brian said got me thinking that sometimes the choice of words we use to express ourselves may be dubious. Thanks a lot