Weird e30 M40 Engine behaviour

[berserkdroid]

Dear sifus,Got a weird problem here with my manual e30 318i with the M40 engine. Even after having replaced the Air Flow Meter, Ignition cables, spark plugs, air filter, fuel filter and Distributor cap (with ori parts, they needed changing anyway), my e30 still idles rough and occasionally with what feels like a misfire. Not only that, the engine jerks violently within the 1000-1500 RPM range, especially when i let up on the gas or take my foot off the gas pedal altogether to let the vehicle coast. The same result is experienced no matter what gear the car is in, but on acceleration in this RPM range, the car behaves just fine. I don't know if this is somehow related to another problem that I'm having with regards to starting. When the engine is cold, it starts fine. When it is hot (or just after switching off) it starts fine. But if i try to start the car after 5 minutes from the time it was turned off, it needs a whole load of cranks for the engine to fire. This i notice started when i had the seal at the injectors changed but at that time the mechanic blamed the starting problem on my ignition cables and almost everything else except for the carpet. Any ideas why?Berserkdroid

 

[anakin]

try to service or change your throttle body...my mech say so, i don't know how true...but it seems that you had already changed almost everything except throttle body....just give it a try...btw me also drive M40

 

[teejay]

try to service or change your throttle body...my mech say so, i don't know how true...but it seems that you had already changed almost everything except throttle body....just give it a try...btw me also drive M40

zainal,

kalau tak tau jangan cakap......lebih baik belajar dari the "cikgu" too bad he is in UK.....haha

 

[teejay]

Dear sifus,

Got a weird problem here with my manual e30 318i with the M40 engine. Even after having replaced the Air Flow Meter, Ignition cables, spark plugs, air filter, fuel filter and Distributor cap (with ori parts, they needed changing anyway), my e30 still idles rough and occasionally with what feels like a misfire. Not only that, the engine jerks violently within the 1000-1500 RPM range, especially when i let up on the gas or take my foot off the gas pedal altogether to let the vehicle coast. The same result is experienced no matter what gear the car is in, but on acceleration in this RPM range, the car behaves just fine.

I don't know if this is somehow related to another problem that I'm having with regards to starting. When the engine is cold, it starts fine. When it is hot (or just after switching off) it starts fine. But if i try to start the car after 5 minutes from the time it was turned off, it needs a whole load of cranks for the engine to fire. This i notice started when i had the seal at the injectors changed but at that time the mechanic blamed the starting problem on my ignition cables and almost everything else except for the carpet.

Any ideas why?

Berserkdroid

its either time to change the carpet. .....or the mech....

sound like a typical fuel pressure regulator giving up, the base of the problems , the rest of the parts was just hit and miss by your stupid mech......

when you changed the injector o rings, it made the pressure of the fuel rail higher, thus the pressure is lost further in the pressure regulator

last but no least, it could also be faulty blocked injectors, either get it ultrasonically cleaned or buy new ones

 

[anakin]

zainal,

kalau tak tau jangan cakap......lebih baik belajar dari the "cikgu" too bad he is in UK.....haha

Errr...salah lagi... maaf la sifu, kita budak baru belajar...last 2 week 'cikgu' ada balik for few days...he bought a few valve(?) from Ah Wai..much cheaper here, he said....

 

[berserkdroid]

Anakin, the throttle body change sounds interesting especially if its from a standard to a wide body type. Anyone else done this?

Teejay, i suspected the same as the starting problem arose at that point but i've been focusing on the injectors. Have checked with Bavarian in SS2 but they don't have injectors in stock. I don't mind changing them as the clicking sound is beginning to get on my nerves.

The fuel pressure regulator, now that was something i hadn't considered. Must investigate this fully.

And after that, i'll pay a visit to that mechanic with a sledgehammer.

 

[teejay]

Errr...salah lagi... maaf la sifu, kita budak baru belajar...last 2 week 'cikgu' ada balik for few days...he bought a few valve(?) from Ah Wai..much cheaper here, he said....

aiyo, why didnt you say so, boleh get to geder old skool taman kosas style......

 

[535i]

aiyo, why didnt you say so, boleh get to geder old skool taman kosas style......

Those were the days ... ...

Wanna gif KL-Seremban another shot ?

 

[teejay]

Those were the days ... ...

Wanna gif KL-Seremban another shot ?

yeah, would like to, but this time ,its my turn to get at least 30 mins headstart......coz i can't keep up with the "3.8"......

 

[Zoggee]

Those were the days ... ...

Wanna gif KL-Seremban another shot ?

535i... drive at 80kmh.
You better rest. You cant take the speed anymore.

Back to topic...

read Masta Teejay says... He is the Masta!!!!

let me add anuder one...might be some air leakage. Check ur bellow...the blck long thing connecting ur thrttle body to the AFM.

 

[berserkdroid]

Thanks Zoggee, but i've just had all the hoses changed as well including the bellow, some of them were as hard and inflexible as iron!

But the problem's still there. Will check the fuel pressure regulator first though.

 

[jagmalhi]

hey mate i experience what u do when i dont use my car for more than 2 days!lol..for a while the problem will be there between 1-2k rpm,rev rev rev for a while then ok..but if driving and it happens,before u change gear,rev ur engine to above 2k rpm then its ok..but if i drive daily problem gone..so i also dunno la..but maybe this will work for u..let us know when u find the solution to ur problem,good luck!

 

[berserkdroid]

Will do, mate. Sent it into the shop today for a steering rack recon and to solve this particular problem. Will let you know how it turns out.

 

[pussy]

sometimes can be the engine ecu.

 

[anakin]

Will do, mate. Sent it into the shop today for a steering rack recon and to solve this particular problem. Will let you know how it turns out.

Deep..problem solved? Kindly let us know will u.....

 

[berserkdroid]

Not yet bro. Checked Fuel Pressure Regulator, Throttle Body, Throttle Position Sensor, Injectors, ECU... all okay.

Maybe the ignition coil... Haven't checked that one yet...