lumpy/rich/smokey running m20 325 manual

[bmw-mad]

Iv'e gone a bit mad with this one

I have a 325 89 cabby here,

The problem I have is it is running veryyy rich and lumpy/spluttering on cold, it clears up slightly once warm but is restricted for power and smokes heavily.

I have changed everything I that I could think of which would have caused this,

All the following has been changed

Spark plugs
Ht leads
dizzy and rotor arm
crank sensor
Blue and brown temp sensors
injectors
Also replaced the inlet gasket
Afm
Idle control valve
checked for air or water leaks
Changed the Ecu in case it was sending the wrong signals
All fueal relays

The Oil also has a smell of fuel which don't look promising

I am seriously scratching my head any ideas?

[BenHar]

TPS?

Ben

[Brianmoooore]

One glaring omission from that list is the thing you should have tested and checked first, and that's the condition of the wires under the lower rubber boot of the plug and socket under the inlet manifold, where the injector loom joins the main engine loom.

[bmw-mad]

One glaring omission from that list is the thing you should have tested and checked first, and that's the condition of the wires under the lower rubber boot of the plug and socket under the inlet manifold, where the injector loom joins the main engine loom.

Checked there not broken or perished away, and two different injector looms and rails have been used (both know tested items)

[Brianmoooore]

Fuel pressure check should be your next move. Ebay kit for around £10 or so will do the job.

[bmw-mad]

Fuel pressure check should be your next move. Ebay kit for around £10 or so will do the job.

Fuel pressure check should be your next move. Ebay kit for around £10 or so will do the job.

I've forgot to add that the fuel pressure is high (can't remember the exact reading) but that's what needs to be resolved.

I'm trying to get to the bottom of what's causing such a high reading?

Also changed the fuel regulator

[Brianmoooore]

If it's high, and the regulator is known good, then the return pipe is blocked.
Take the return hose off of the reg., fit a length of hose draining into a can, and re check the pressure.

[bmw-mad]

If it's high, and the regulator is known good, then the return pipe is blocked.
Take the return hose off of the reg., fit a length of hose draining into a can, and re check the pressure.

This has also been tried, it was still showing 70-80 psi

A adjustable fuel regulator was also tried but it would not adjust enough and was throwing out similar readings.

[bmw-mad]

Any ideas?

[Brianmoooore]

If the fuel pressure regulator is good and the return pipe is clear, it's impossible for the fuel pressure to be higher than the rated pressure of the regulator, unless your fuel pump has such a high fuel flow rate that it overwhelms the regulator.
In practice, it should be somewhat lower than the pressure marked on the regulator, since the reference pressure is that inside the inlet manifold plenum, which is always lower than atmospheric when the engine is running.

[bmw-mad]

If the fuel pressure regulator is good and the return pipe is clear, it's impossible for the fuel pressure to be higher than the rated pressure of the regulator, unless your fuel pump has such a high fuel flow rate that it overwhelms the regulator.
In practice, it should be somewhat lower than the pressure marked on the regulator, since the reference pressure is that inside the inlet manifold plenum, which is always lower than atmospheric when the engine is running.

That should be the case,

but the pressure is rapidly high.

The fuel pump has also been changed with good known working ones but still the same.

[BenHar]

Are you sure your test gauge is ok?

Ben