Engine light. Fault code 2A2F DME Mixture control

Newbers

Active member
St Albans (one days march from London)
Hi All

I've had the yellow engine light displayed for a little while now. Just had Inspection 2 completed by Specialist Cars and they said the fault code is 2A2F which apparently indicates there is an issue with the DME mixture control and that the mixture is too lean.

Their first investigation step would be a smoke/emissions test.

The engine is apparently running fine otherwise. 60,000 miles.

Questions:

Does any one have experience of this code and what caused it?
For this type of issue does the stealer have any diagnostic capability advantages or would I be as well to go to a local independent or some sort of specialist?
 
Check lower intake boot for holes/leaks. Any leaks in after the maf could indicate/lead to lean running issue.
 
Chris_D said:
Check lower intake boot for holes/leaks. Any leaks in after the maf could indicate/lead to lean running issue.

Thanks Chris_D
Do you mean in part 1 here?:
 
Yeah looks lke u have different engine to mine (m54). Which do you have?
On mine i had lean codes for both banks at same time so discounted o2 sensors as culprit.
Looked for holes in the intake from maf to tb and sure enough had a holy lower intake boot. Replaced boot and codes went away.
First/cheapest diagnostic would be to check for leaks anywhere in intake path from the maf. Could also be a dodgy maf.
 
I think the coupe engine is an N52(?)
The principle is the same tho. I'll take a look and see if there's anything obvious....
 
Hi, got this same code aswell as 2D06, I am totally new to working on cars, and not quite sure what I should be checking for. Any help greatly appreciated.
 
Agree with @Chris-D, lean codes usually down to an air leak in the system after the Maf, quite common to find holes/splits in the intake hoses either top one or bottom or the idle control valve offshoot hose on the upper one. If they are intact then look elsewhere across the engine for leaks, a smoke test is the best method for finding leaks. Once unmetered air gets in after the Maf it gets picked up by the exhaust sensors and the mismatch between what the car has seen go through the Maf and the extra air picked up in the exhaust makes the car think its running lean. It tries to compensate for this by telling the injectors to add more fuel to richen the mixture. It will keep doing this until its adding up to 20% more fuel, realises there is something wrong when it dosn't correct and sets the EML to draw attention to the condition. Have had split hoses, cracked cam covers and failed dipstick O rings and failed Oil Cap seals not to mention a leaking sucking jet valve down by the throttle body be the cause of air leaks on various models I have worked on. Smoke test will find the less obvious leaks which makes it easy to pinpoint the cause. Air leaks will affect the running and affect your mpg with more frequent visits to the petrol station, button up any leaks and you will see a vast improvement to your mpg.
 
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