Running issues. 318IS

[davelarge]

Hi I have a 1991 318is which I have been restoring, as it stands the engine starts and idles hot or cold but if I apply throttle to quite a high RPM when the revs fall to idle again the engine cuts out. Also it produces alot of white smoke when hot idling.

Thanks any advice would help, ive changed the vacuum pipes and removed the throttle heater, although I havent changed the ICV.

[DHFiS]

What rpm does it idle at when started and warm?

[davelarge]

Around 1000rpm although i have played around with the control screw as it was idling to low previously.

[Grrrmachine]

Which control screw? The throttle stop, or the one on the AFM?

[TPS]

I wouldn't muck about with Control Screw(s), whole world of trouble there.

[davelarge]

The throttle stop.. Oops ill make sure i dont touch the other one then, i only adjusted it slightly

[TheDutch]

Also it produces alot of white smoke when hot idling.

I'd be far more concerned about this than the stalling issue.

[davelarge]

Im concerned about both. Do you know what the smoke could mean?

[TheDutch]

If it's white as you say, then that normally means water vapour, and that normally means coolant, and that normally means head gasket failure, and that normally means dollars/euros/yens etc., and that normally means swearing and resentment, and that normally means second thoughts about this whole bloody idea, and that normally means car in crusher and good riddance to heap of damnation. But it might just be a bit of moisture build up, how long does it do it for?

[davelarge]

From what i know white smoke normally means burning water or coolant? but it hasnt got any gunge in the coolant and wouldnt it over heat?

[davelarge]

ill have to let the car run for a while tomorow and time it.

I guess your right though if that is the case ill either break the car or try and source another usable engine for the right price.

[rich318i]

Air mass meter sound's fooked to me had the same prob in my 318i. give the air mass a wack on the top of the black box see if it helps, worked for me everytime.

white smoke prob. looked at the oil cap and pray no cream looking oil on the cap.

[davelarge]

hmm ill have a look at the air mass meter then mate.

I need to get to the bottom of this smoke problem, i checked the oil rez when i got the car an there was no cream :/

[rich318i]

if your not losing water dont worry. if you are then you got a cracked head

[johnl320]

Have you cleaned out the ICV?

[DHFiS]

Around 1000rpm although i have played around with the control screw as it was idling to low previously.

If the idle is that high then I'd guess the butterfly isnt closing in the TB so the ECU isn't running the engine in idle mode (which should be around 800 rpm).

Take the inlet hose off and check that both butterflies are fully shut.

[davelarge]

if your not losing water dont worry. if you are then you got a cracked head

Deffinately not losing water.

Have you cleaned out the ICV?

Yes ive cleaned it with carb cleaner

If the idle is that high then I'd guess the butterfly isnt closing in the TB so the ECU isn't running the engine in idle mode (which should be around 800 rpm).

Take the inlet hose off and check that both butterflies are fully shut.

The top valve is slightly open ill adjust the screw to correct this, do you think that could be causing the cutting out issue?

[DHFiS]

I expect it is part of the problem

[davelarge]

Ive adjusted the throttle stop so that the top butterfly valve is closed and it has stopped the car from fully cutting out, but it still bogs down when full throttle is used, it idles fine and if you gradually build the revs it will revs high but if you go straight to wide open throttle it just stutters and when releasing the throttle returns to normal idle.

[Grrrmachine]

You've changed the vacuum pipes, but have you checked for air leaks? Spraying a can of carb cleaner around the hoses while the engine is idling will help show up any leaks; the engine will rev higher from sucking in the carb cleaner.

[DHFiS]

Did you renew the gasket when you did away with the throttle heater?

[davelarge]

You've changed the vacuum pipes, but have you checked for air leaks? Spraying a can of carb cleaner around the hoses while the engine is idling will help show up any leaks; the engine will rev higher from sucking in the carb cleaner.

checked for leaks with the carb cleaner like you said and found nothing

Did you renew the gasket when you did away with the throttle heater?

No i used the exhisting one as it looked in good condition

[DHFiS]

If you are 100% sure there are no air leaks then the next place to look would be the AFM. Does it still have the bung covering the screw to the right of the electrical connector?

[davelarge]

No theres no bung over the screw.

[DHFiS]

So someone has already had a go at resetting it.

Since you have owned it has the car ever idled correctly?

[davelarge]

when i first got the car it had been sat on the previous owners drive un-used for over a year and it struggled to idle but I replaced all the vacuum pipes and it seemed to solve it, it will happily idle now but its just when throttle is added it bogs down.

[DHFiS]

If you can get hold of another AFM then you could try it in your car and see if the fault is still there.

Anything else I suggest now will just be a guess.

[Brianmoooore]

£46 spent on an injector refurb would be money well spent.

[davelarge]

If you can get hold of another AFM then you could try it in your car and see if the fault is still there.

Anything else I suggest now will just be a guess.

thanks mate ill try the AFM and see how it goes from there.

£46 spent on an injector refurb would be money well spent.

I look into it cheers

[DHFiS]

thanks mate ill try the AFM and see how it goes from there.

If you take the square black lid off the AFM you will be able to see the spindle the air flap turns on, it swings the wiper arm along the copper track on the PCB.



Just check it can more freely.

[davelarge]

Checked the AFM and its operating fine as the video shows :/

[davelarge]

Im still struggling with this but ive spoken to a few people with more experience than i have and they think its something wrong with the way the car controlls the air to fuel mixture when the large butterfly valve opens.

Can anyone shed some light on what this could be? TPS or blue plug maybe?

[DHFiS]

Im still struggling with this but ive spoken to a few people with more experience than i have and they think its something wrong with the way the car controlls the air to fuel mixture when the large butterfly valve opens.

Can anyone shed some light on what this could be? TPS or blue plug maybe?

Have you had the air/fuel ratio checked?

[davelarge]

No is there any way of doing this myself?

[Brianmoooore]

£46 spent on an injector refurb would be money well spent.