Euro E30 M42

[318_IS]

Hi guys,

I've bought myself a couple of months back an E30 318iS. I'm living in europe so the car is euro-spec.
She was running fine since the day i bought her but last week a strange problem came up  . When the car
is stationary running everything is ok: idle is good, goes well in revs without stuttering, doesn't stall...But when
i actually drive it, the car losses power after about 2 minutes of driving and eventually stalls. I can restart her
immediately and drive with it for again about 2 minutes and so on and so on. I already did a lot of research
on this forum because i'm a noob when it comes to engines  . A leak in one of the vacuum hoses is something
i came accros a lot. So checking those would be a good start i guess?
Thank in advance for any input 

[keflaman]

Hi and welcome to the forum.

The first thing that came to my mind was the catalytic converter is plugging up. Your car may, or may not, have one. 

[318_IS]

Hi and welcome to the forum.

The first thing that came to my mind was the catalytic converter is plugging up. Your car may, or may not, have one.

It does have one. I'll check it out if it's plugging up. Maybe i'm just better off with smashing the whole inside out of the catbox
because where i live (Belgium)cars older then 25 years don't have to meet exhaust regulations.

[318_IS]

Hi and welcome to the forum.

The first thing that came to my mind was the catalytic converter is plugging up. Your car may, or may not, have one.

I've removed the cat. It was plugging up. The car is now driveable but it's still not ok. It won't rev over 3500rpm. When i do, the engine start to sputter...

[lambertius]

Hi and welcome to the forum.

The first thing that came to my mind was the catalytic converter is plugging up. Your car may, or may not, have one.

I've removed the cat. It was plugging up. The car is now driveable but it's still not ok. It won't rev over 3500rpm. When i do, the engine start to sputter...

Go by a can of Carbie Starterfrom an auto store - its ether, very volatile. Spray it liberally around all the hoses at the intake. If the engine sputters or surges, you have an air leak, and it will help you identify where.

[318_IS]

So i've removed my clogged up catalytic converter. Should i connect or disconect the mysterious black/grey wire plug because it has something to do with the cat as far as i can recall? (See pictures, the one where's a sticky about the hot starting problem) I've now tested my airflowmeter which is ok, throttle position sensor ok, water temp sensor ok, cam sensor ok and crank sensor. The actual resistance of a crank sensor should be 500 Ohm plus-minus 50 but mine is 480 Ohm. It's the only sensor which is a little bit of the reference value but that shouldn't be a problem i guess??? Gonna do the spaytest with carbiestarter tomorow. Does anyone know what the thing is with the two rubber tubes?(blue circle) On one end they are fitted to some kind of sensor. And on the other end; one is not connected and the other goes to what seems some kind of breather valve? And from that 'breather valve' a thicker rubber tube goes to nowhere(green circle)...  Feel free to share thoughts!

[DesktopDave]

Definitely plug all the vac leaks before going any further. I'm not sure what that silver thing is mounted to the fender, but it looks like an aftermarket device. I'd be tempted to disconnect it and see if things improve. I've also seen some old BMWs with coolant temp vacuum switches that look like those paired vac tubes, but I have no idea why that'd be there like that. I'd be very strongly tempted to delete the throttle body heater and related vac tubing under the intake manifold. You'll need a new intake gasket but it's otherwise a pretty simple job.

I'd also test fuel flow & pressure. If your fuel filter is clogged (or fuel pump is on the way out) it'll starve the motor at high RPMs. The mystery plug on the firewall should be connected to enable the CO potentiometer in the AFM. I'm not sure your AFM even has a CO pot installed; our units over here did not. I'd leave it disconnected.

I'd also pull the cyl head cover to see if the cam gears look OK. You can easily check if the timing chain is loose and the cams are timed correctly. While you're in there, maybe pull the spark plugs and see if they look OK. Some light brown deposits are OK, sooty black deposits indicate too much fuel. Heavy black oily deposits could be bad news with valve or piston sealing. One or two washed plugs could indicate a blown head gasket.

Have you run any tests to see what the motor compression looks like? A leak-down test from a pro is usually pretty cheap and will give you a great baseline on motor health. If the motor has low compression, it will burn a lot of oil & plug up the catalyst. Used oil analysis is a useful tool too, if you have a sample of the motor oil with some mileage on it.

[cristimm]

That think is an aftermarket emission device. You can remove it but you might get trouble on technical inspection (check the regulations from your country).

[318_IS]

That think is an aftermarket emission device. You can remove it but you might get trouble on technical inspection (check the regulations from your country).

No emission regulations here 

[318_IS]

Definitely plug all the vac leaks before going any further. I'm not sure what that silver thing is mounted to the fender, but it looks like an aftermarket device. I'd be tempted to disconnect it and see if things improve. I've also seen some old BMWs with coolant temp vacuum switches that look like those paired vac tubes, but I have no idea why that'd be there like that. I'd be very strongly tempted to delete the throttle body heater and related vac tubing under the intake manifold. You'll need a new intake gasket but it's otherwise a pretty simple job.

I'd also test fuel flow & pressure. If your fuel filter is clogged (or fuel pump is on the way out) it'll starve the motor at high RPMs. The mystery plug on the firewall should be connected to enable the CO potentiometer in the AFM. I'm not sure your AFM even has a CO pot installed; our units over here did not. I'd leave it disconnected.

I'd also pull the cyl head cover to see if the cam gears look OK. You can easily check if the timing chain is loose and the cams are timed correctly. While you're in there, maybe pull the spark plugs and see if they look OK. Some light brown deposits are OK, sooty black deposits indicate too much fuel. Heavy black oily deposits could be bad news with valve or piston sealing. One or two washed plugs could indicate a blown head gasket.

Have you run any tests to see what the motor compression looks like? A leak-down test from a pro is usually pretty cheap and will give you a great baseline on motor health. If the motor has low compression, it will burn a lot of oil & plug up the catalyst. Used oil analysis is a useful tool too, if you have a sample of the motor oil with some mileage on it.

Thanks for the advice! I think i'm going to start with the throttle body heaterplate removal and refurbish the vac hoses. This is probably the easiest way for me (because like i already said: i'm a noob when it comes to engines  ) to find a solution on my engine problems. Search give me this http://www.m42club.com/forum/index.php?topic=3621.0 and this http://www.m42club.com/forum/index.php?topic=2742.0.
1 is a diy to get rid of the heaterplate and 2 is a diy to clean up the vac hoses and also to get rid of the heaterplate. Not all of the pictures are visible on the second diy  . Does anyone know where i can find a full version or some additional info on these how to's? This is gonna be huge for me so i want to inform myself as much as possible before i tackle this   

[318_IS]

Complete intake and heaterplate are removed. I've read most of 'the mess under the intake' and started with it anyway  . I'm gonna start rebuilding it when i get my gaskets... I'm going to get the injectors cleaned professionaly but i can't pull them out of the intakemanifold and i can't pull of the fuelrail (see 2nd pic). Doing something wrong here? I also did find a kind of sandlike deposists on the inside of the intakemanifold(see 3rd pic)?

[Darky]

Hi

Sand like? Looks like oil deposits. Which leaves me to suspect valve stem seals. Did that come from the intake manifold? Also possible that the engine just has not been touched since it was made. Catch can time!

Where you blowing smoke on startup?

Cheers Rohan

[318_IS]

Hi

Sand like? Looks like oil deposits. Which leaves me to suspect valve stem seals. Did that come from the intake manifold? Also possible that the engine just has not been touched since it was made. Catch can time!

Where you blowing smoke on startup?

Cheers Rohan

It smells like oil but it has a granular structure and is kinda  sticky. It was mostly around the injectornozzles in the intake manifold (see pic). She already has 195k km (about 121k miles) on her dial so i guess it's normal about the deposits. She doesn't blow smoke when i start her. I removed my injectors with a lot of struggle out of the fuelrail and manifold. I noticed a small crack in one of them...Shouldn't be a problem i guess?

[colin86325]

I've had that stuff in several engines I've taken apart.  I think it's just a type of carbonization.

Does the metal of the injector body extend all the way to the top?  I did see an M20 injector that leaked fuel, but it was at the parting line between the lower metal and the upper stem of the injector.  Most likely you'll be ok, but monitor it for a few days.  You might even want to reinstall it in a position on the fuel rail where it it most easily observed.

[318_IS]

Finally had some time on my hands to redo the vac hoses. I've also removed the TB heaterplate. But now i'm really struggling to bleed the cooling system  . Steam would come up on the bleedscew. How much coolant does the system contain? And do i have 2 bleedscrew? I've read it somewhere on the web. There should be another bleedscew somewhere around the connection flange where the 2 radiatortubes go to? And how long does the bleedingprocess take?