strange starting problems

Sun Apr 22, 2012 11:09 am

when the car is started it takes a few cranks to turn over and needs a tickle off the pedal,when it does start it coughs and splutters for 10/15 seconds or so then runs fine.

After it has been driven for a bit and pull up at the lights the revs usually hovers around 1000rpm mark.
Pulls really well managed to get it to hit 130mph over thelwall until it hit the limiter last night.

just want to get the starting problem fixed,any ideas where to start looking for the problem.

1990 m40 1.8

Mon Apr 23, 2012 1:53 am

bimanut wrote:revs usually hovers around 1000rpm mark.
Pulls really well managed to get it to hit 130mph over thelwall until it hit the limiter last night.

And your need to highlight the above is to show people the size of your dong is it?

Ok check the BTS, AFM, dizzy cap and rotar. Fuel injectors and coil. Might be worth checking the wipers as it has been known to cause alot of issues described. Trye pressure while your at it, make the the valve caps are on and tightened to the correct torque.

OR

Mabey you f***** it driving like a D***??

How was it before you drove it like a D***?

Mon Apr 23, 2012 3:33 am

someones too aggy ! ^^^ prime example of why people leave the zone , guy asked a simple question his choice to do that speed , heck standard 2.5s can do 160 calm down or do one

bimanut , i dont know these engine well but check for split hoses, boots ect .hope someone who knows more and is polite cones to your rescue with sound advice

Mon Apr 23, 2012 9:08 am

This has been covered so many times and is in the Wiki but a summary for the M40 is:

The Throttle Position Switch under the throttle body must "click" as the throttle is completely reaxed...some idiots turn in the factory set screw on the butterfly stop to suppossedly adjust the idle and this moves the switch actuator off the TPS.

The Blue temperature sensor needs to be tested, hot and cold, right at the ECU to see if it is working.

The ICV valve must be cleaned nicely.

Check for vacuum leaks everywhere...especially the hoses under the intake manifold and the gasket for the tappet cover and maybe the intake manifold gaskets themselves.

Fastest I have ever taken my M40 is 100 mph on a straight road in the middle of nowhere in broad daylight

Mon Apr 23, 2012 10:01 am

Idle problems are indeed a common E30 problem:

http://www.e30zone.net/e30zonewiki/inde ... ake#Idling

Got through the list systematically.

And if you've got the car to 130mph, I'd expect the tyres to be undersized, making the speedo read inaccurately

Mon Apr 23, 2012 5:06 pm

askjeevesplease wrote:
bimanut wrote:revs usually hovers around 1000rpm mark.
Pulls really well managed to get it to hit 130mph over thelwall until it hit the limiter last night.
And your need to highlight the above is to show people the size of your dong is it?

Ok check the BTS, AFM, dizzy cap and rotar. Fuel injectors and coil. Might be worth checking the wipers as it has been known to cause alot of issues described. Trye pressure while your at it, make the the valve caps are on and tightened to the correct torque.

OR

Mabey you f***** it driving like a D***??

How was it before you drove it like a D***?

Jog on d**k

Mon Apr 23, 2012 5:09 pm

Grrrmachine wrote:Idle problems are indeed a common E30 problem:

http://www.e30zone.net/e30zonewiki/inde ... ake#Idling

Got through the list systematically.

And if you've got the car to 130mph, I'd expect the tyres to be undersized, making the speedo read inaccurately

15" bbs with 195 45

The engine has been rebuilt by raw motorsport.
I think i`ll start with the blue sensor and icv.

Mon Apr 23, 2012 7:23 pm

bimanut wrote:
15" bbs with 195 45

Two inches smaller than standard. Speedo will be over reading by a lot.

Ben

Tue Apr 24, 2012 11:25 am

who cares what speed you/he/they/i did / have done/claimed to have done etc, this is technical help right?

most likley and easyiest thing to check is your icv,

.....................failing that it could be your warp drive?

Tue Apr 24, 2012 5:15 pm

This symptom was already there before i decided to see what it would do.
Thelwall is a nice stretch of motorway when empty so 10pm on a saturday night it was empty.

Wether it actualy reached the speed it said on the clock is erelivent,the fact that it has a starting problem is.
As i said it drives fine but doesnt like starting and has a high tickover.

Thanks for the `helpful` comments..

Tue Apr 24, 2012 5:39 pm

I'd whip out your ICV and clean it out with carb cleaner first. You can also connect 12v to it and listen to it snap open as a way to make sure its working I believe.

Wed Apr 25, 2012 8:25 am

mcbonio wrote:I'd whip out your ICV and clean it out with carb cleaner first. You can also connect 12v to it and listen to it snap open as a way to make sure its working I believe.

You can apply 12 volts to it but only briefly to get it to snap open and close...if you leave 12 volts connected you could burn out the ICV as it normally gets a variable pulse (Pulse Width Modulation) to operate it...not constant 12 volts.
I have cleaned the ICV out with petrol and sprayed some Q20 on it and checked that it snaps open and closed nicely...a month or two later it gets gunged up again and I have to repeat the process.

Wed Apr 25, 2012 1:45 pm

That would normally suggest you're getting too much oil coming in from the rocker cover breather hose. It gets sucked into the intake system and usually collects in the throttle body, gumming up the TPS, but if your ICV is suffering you might want to look at why so much oil is getting into there in the first place.

Wed Apr 25, 2012 6:42 pm

Grrrmachine wrote:That would normally suggest you're getting too much oil coming in from the rocker cover breather hose. It gets sucked into the intake system and usually collects in the throttle body, gumming up the TPS, but if your ICV is suffering you might want to look at why so much oil is getting into there in the first place.

I agree....where does all the gunge come from? This motor uses no oil...I do not even have to top it up between oil changes. Car goes well and does not smoke and uses no water.
I can only think that some of the fuel that I get here in this small town is a bit suspect and all our fuel has a 20% addition of petrol derived from coal.

I am probably exaggerating a bit...maybe I go about three to four months between cleaning out the ICV but I definitely know it is time to do so when the car starts to idle badly.