m20b20 facelift missfires alot - need help now (solved)

[Egat123]

i have a -88 320 (m20b20facelift-no lambda) wich i have changed the engine wireing harness on, the harness is from a 1990 touring automatic(facelift) i use the "old" ecu

when i drive the car misfires and backfires alot it wont go over 2000 rpm. but if i disconnect the blue tempeture gauge it runs much better but it misfires and wont go over 4500rpm.

things ive done/ changed: the wireing to the injectors
3 different afm's
blue temp
new leads plugs and distrubutor rotor
triggersensor

is possible the car thinks its in P(park) og something?

iam stuck please help

[arrisbmw]

why did you fit another wiring harness ? if it was in P it won,t move at all. how many miles up ?
and what is lmm

[arrisbmw]

has it had a new cam belt recently ?

[Egat123]

why did you fit another wiring harness ? if it was in P it won,t move at all. how many miles up ?
and what is lmm

i did not know it was from touring before after i buoght it... lmm=afm

my car is manual

[Egat123]

has it had a new cam belt recently ?

just beforw i bought it2 years ago

[Egat123]

ive made a video, this is full speed 1 and 2nd gear.

[arrisbmw]

if the cam is badly worn, engine won,t rev to max. have you done a compression test on the engine ?

[Egat123]

yes its good... weird thing is with the blue tempsensor, if connect stops at 2000´ish rpm and 4500`ish rpm when disconnected

[arrisbmw]

you can check the blue temp sensor at the ecu. iirc you need to disconnect the multi plug. then work out what two pins to connect multi meter too. there is a post on here about it from Brian , he,s your man . i did it on mine a while ago but can,t rember all the details, search on here ,

[Egat123]

you can check the blue temp sensor at the ecu. iirc you need to disconnect the multi plug. then work out what two pins to connect multi meter too. there is a post on here about it from Brian , he,s your man . i did it on mine a while ago but can,t rember all the details, search on here ,

bluetemp is brand new. but do you mean maybe there is a failure in the cables somewhere?

[Egat123]

please help! i also tried to change the ecu with a same nr on it. no difference

[Speedtouch]

Could be that the cambelt has been put on one or two teeth out. I had similar issues on a 1984 320i when I got Halfords to put a new belt on - which then wouldn't go over about 4,500 rpm, also on a 1999 Fiat Seicento Sporting, which never seemed to run quite right.

[Egat123]

just checked the marks and they are spot on

[arrisbmw]

you can check the blue temp sensor at the ecu. iirc you need to disconnect the multi plug. then work out what two pins to connect multi meter too. there is a post on here about it from Brian , he,s your man . i did it on mine a while ago but can,t rember all the details, search on here ,

bluetemp is brand new. but do you mean maybe there is a failure in the cables somewhere?

yes could be wiring issue. search Brian Moore , iirc there was a post about checking blue temp sensor at e.c.u.
just thought something else . there a connector under the inlet manifold that gets corroded , electrical. I believe it comes from the injectors

[arrisbmw]

also have you done a compression test. to check the engine physical condition . valves , rings on pistons and bore wear e.tc.

[arrisbmw]

has you car got a cat fitted ? your issue could be exhaust blockage related.

[Egat123]

compression test done. pressure is even and good.

yes .. bought a brand new injector wireharness

its -88 mod, just before the cat . so it no cat and no lambda

[arrisbmw]

oh . sounds like your tried a lot . have you check the fuel pressure ?. I assume your fitted a new fuel filter.

[Egat123]

ye.. feel like ive tried everything... no i have not.. because when i disconnect the bluetempsensor it flys away up to 4500rpm.. so i dont think fuel is problem?

[Brianmoooore]

Why did you change the original wiring harness, and which harness?

[Egat123]

becauz it was ugly and cut open and connected again many places.
and it had little bad. but really bad ofter the change

[Brianmoooore]

Check the condition of the wiring under the rubber cover of the plug and socket below the inlet manifold that joins the injector loom to the rest of the engine loom. This is a common place for severe corrosion to occur when water gets trapped inside the cover, and it doesn't follow that just because the loom was good in its original home it is still good now, after being bent and twisted around.

[Egat123]

ye allright i will check thst tomorrow. thanks

[Egat123]

okey... so i checked the wireing it seems fine. i measured the connections to the injectors. ca 14v on all of them, today i even tried to change the coil. car is the same . what to do??

[Egat123]

changed the fuelpump! everything back to normal. fuel pump was only giving 1bar of pressure . so when it limited on 4500rpm it was becuz it did not get enough fuel.

[arrisbmw]

fuel pressure that was a good shout by me , lol .
how did you find the fault ? inline gauge ?

[Brianmoooore]

Would be interesting to know exactly what's happened to that pump. E30 pumps normally fail by either wear in the pump gears causing them to jam up, or through the copper commutator in the motor wearing away.
The former doesn't significantly affect the pump output when its working - it's the common fault where the car either fails to start, starts and then dies, or just dies on the road, can be restarted by thumping the top of the pump, whereupon it runs fine until the next time.
The second mode of failure will cause the motor to lose speed and run roughly, which should be audible when the car is running. The pump will lose performance, but should still be more than capable of supplying the car's needs, until so much of the commutator has worn away that the pump will fail to start more often than not.
I wonder if there was some kind of failure of the plastic 'pipe' that links the pump itself to the steel outlet pipe of the assembly?
Was the pump an OE one, or a bodged in ebay type replacement?

[Egat123]

fuel pressure that was a good shout by me , lol .
how did you find the fault ? inline gauge ?

yupp!

i used what i had, wich was a gauge from a comptester... so connected it to the fuel hoes before the rail and before the filter to check if it was the pump or the filter that was faulty..