Help /Advice needed - car is 'running rich'??

[si911t]

Hi

I have been told by MOT inspector that car is running rich? what does this mean ?

I will explain problem. when im stationary with car on, the whole car seems to shake , rumbling noise, sounds like exhaust is blowing but it is not as that was changed recently. The revs stay still at a steady 750-800 so what could it be ?

Also seems to be drinking a lot of petrol alot more than i was expecting and what it should be.

someone suggested a crypton tune .. any ideas ?

Thanks

ps. car is 89 325i sport

[eltel]

blue temp sensor could be worth testing.. also the mixture on the afm if it has been tampered with previously.

where is the noise coming from?..it could be unrelated to your mixture but maybe the viscous fan is faulty causing a cool engine

did it fail the mot on the emissions?

[daimlerman]

Two temp sensors,for this purpose ignore the brown one.

Use a meter set to resistance(ohms)to check the blue sensor both cold and hot.
There should be a marked difference between the two readings.

Replacements are readily available from GSF.

[LuckyP]

I have been told by MOT inspector that car is running rich? what does this mean ?

To answer your initial question, "running rich" means there's too much fuel in the air/fuel mixture that the engine burns (i.e. the mixture is fuel-rich).
This would explain why you've noticed excessive fuel consumption.

Pete.

[si911t]

I have been told by MOT inspector that car is running rich? what does this mean ?

To answer your initial question, "running rich" means there's too much fuel in the air/fuel mixture that the engine burns (i.e. the mixture is fuel-rich).
This would explain why you've noticed excessive fuel consumption.

Pete.

tHANKS .

So next question , what is making the air and fuel mixture go wrong? is it something simple or doe sit have to go in to garage to get fixed?

[LuckyP]

Either too much fuel or too little air.

Too little air is normally compensated for, as the air-flow meter (AFM) measures this and the engine ECU should put in the corresponding amount of fuel.

In previous replies, the guys suggested checking the blue temperature sensor. This sensor measures the coolant temperature and gives this information to the engine ECU. If it has failed and is permanently giving a "cold" signal to the ECU, the ECU will deliver more fuel to the engine (because a cold engine needs more fuel to run smoothly). Also, the blue temp sensor is a fairly common fault.

Having said that, there are a number of things that could cause your problem - there are a few other ideas in this thread:
http://www.e30zone.net/modules.php?name ... c&t=175288


Pete.