Help! please for the love of God

[euroe30]

I have this constant ongoing issue with my E30
its an 84 323i (euro) with the M20 motor.
It loves to cut out and buck like a ravid horse at higher RPM's. It only does it when its at operating temp. never when its cold. If i drive it in the city its fine, but when i maintain a certain RPM for awhile it goes crazy. Remember, its a euro car so i donthave an 02 sen. or a crank sens.
i have replaced the following parts to try to cure it. the tach doesnt go all the way to zero when this happens. it slowly drops. therefore i dont think its ignition related.
cap
rotor
plugs
wires
fuel pump
fuel pump relay
fuel filter
coil
and so on.
any help would be wonderful. i have spent 1500.00 at numerous repair shops and they cant figure it out. could it be my afm or computer???
please, if you have any answers, feel free to let me know. i am sick of throwing parts at it. if i dont fix it soon i will sell it.

[winstontj]

First check the chip in the ECU. Post up the numbers and someone will tell you what you have. Second what RPM is it cutting out at? Is it a rev limiter?

Before you start replacing everything under the roof figure out the basics. Have any mods been made to the car? Motor? Do you have a stock chip? Rotor? Perhaps you have an eta chip in an I car and your revvs are cutting out lower than they should be because of the chip???? Just a thought...

[AndrewBird]

I would check the AFM.

http://www.r3vlimited.com/board/showthread.php?t=51257&page=4&highlight=AFM

Post number 71. Could be your problem.

[euroe30]

the car is bone stock except for the wires, and after market intake kit it doesnt have a rev limiter. this problem recently started. i have had the car for a long time and never had this problem until about 2 months ago. i dont have a chip either. once it is warm is when it acts up. it does it mostly on the freeway or when i maintain a certain rpm for a distance. but sometimes it will do it at any rpm. i am having trouble finding an ecu and afm because its a euro car.

[Rocla]

Perhaps you have an eta chip in an I car and your revvs are cutting out lower than they should be because of the chip???? Just a thought...

Euro m20b23 engine has L-jetronic injection, l-jetronic ECU can't be chipped.

Only l-jet ECUs will work, so no he has not e ECU or chip.

L-jetronic revlimiter is located on distributor rotor, IIRC 1984 323i should have 6400rpm limit.

AFM would be my guess, or the TPS, it the symptoms only occur on WOT or near WOT.

EDIT: check the intake boot and brakebooster vacuum hoses if you haven't yet.

[euroe30]

it doesnt have a tps. its a euro car. what is WOT? so far in the last few days, i have replaced a couple of grounds. (the one on the valve cover that goes to the batt. tray and then some fuel injection grounds. still no dice. i pulled the top off of the AFM and checked it for dead spots and scratching. it all looked great. im really frusterated becasue i have taken it to numerous shops and spent now almost $2000.00 yes $2000.00 i am baffled that no one at these shops can tell me what the hell is wrong with it. im wondering if my cat is going out becasue it smells funny when it happens. almost a burning smell not sulfur though like you would normally smell. i will give it a valve adjust for the hell of it and see if it cures it. if that doesnt work someone can buy it from me. nevermind, i know what WOT means. sorry i spaced!! Wouldnt my intake boot cause it to do that everytime i drive it? and when its cold? i checked my vac. lines. they are all brand new and tightly clamped

[Turf1600]

WOT is wide open throttle - ie floored

[Rocla]

it doesnt have a tps. its a euro car. what is WOT? so far in the last few days, i have replaced a couple of grounds. (the one on the valve cover that goes to the batt. tray and then some fuel injection grounds. still no dice. i pulled the top off of the AFM and checked it for dead spots and scratching. it all looked great. im really frusterated becasue i have taken it to numerous shops and spent now almost $2000.00 yes $2000.00 i am baffled that no one at these shops can tell me what the hell is wrong with it. im wondering if my cat is going out becasue it smells funny when it happens. almost a burning smell not sulfur though like you would normally smell. i will give it a valve adjust for the hell of it and see if it cures it. if that doesnt work someone can buy it from me. nevermind, i know what WOT means. sorry i spaced!! Wouldnt my intake boot cause it to do that everytime i drive it? and when its cold? i checked my vac. lines. they are all brand new and tightly clamped

Your car has TPS =thortle position sensor, your car hasn't got crank position sensor.

The boot might be only slightly damaged, so it only would leak when hot and whe it strecthes a bit when the engine moves.

[92 mtechnic cabrio]

dude

AFM

[euroe30]

i didnt know my car had a tps. i was told it was the older style m20 motor that didnt come with a tps. i checked the air flow meter. i pulled the top off of it and looked at it and didnt see any scratches on the film at all. it looked really nice actually. if i do have a tps, is it the sensor under the intake boot with a plug on it? if so that is covered in fresh oil. what does that mean? i pulled the intake boot off and looked at it for about an hour checking to see any hairline cracks. i didnt find any

[NC325iC]

have you checked the coolant temp sensor?

[euroshark]

L-jetronic revlimiter is located on distributor rotor, IIRC 1984 323i should have 6400rpm limit.

There is a soft rev limiter within the L-Jet system too, the ECU cuts off fuel to the motor. You could have a dying ECU...

My dad's L Jet ECU died for months and kept getting weirder and weirder until one day it would only fire one batch of cylinders.

[euroe30]

i have not checked the temp sens. yet. i have another ECU that i have and am going to put it. i know that the temp sens. has a lot of corrosion around it. and a bit of coolant. maybe that will be my next part! i appreciate all of the help.

[emi325i]

do you have those twist connectors for the various engine harnesses? i had a loose one and it caused a similar problem.

[euroe30]

what twist connectors?