small electric motor sound kinda like a small vacuum cleaner under the hood of the rig when it is running.


heard it today at a stop light. had the radio turned down and i heard this motor sound winding up and then stop.

did not hear it again. im certain its the small black cylinder shaped deal on the passenger side near the firewall.

 

Yep, I hear this thing occasionally, isnt it something to do with the Fuel Return??

 

It is the emissions air pump. It pumps air into the exhaust (at the headers) to clean up the exhaust gases. It's sort of a band aid to make the engine pass emissions instead of going to a newer engine design. Some engines have secondary air injection, some don't. Depends on the efficiency of the motor as a whole.

Cheers,

Pete

 

then i shant not worry about it


cheers butt heads

 

Sloppyjoe, I would worry about it if it is turning on frequently after the engine has reached operating temeprature.

If that is the case than you have a rich condition (unburnt fuel) detected by the O2 sensors that the ECU is not able to manage due to bad sparkplugs, dirty injectors, a leaking intake manifold gasket, a loose intake pipe near the MAF sensor, etc. etc.

The pump operates normally under these conditions. The air pump turns on a cold start. That should last about 30 seconds or so. It also may come on every once in a while and rarely, after the engine has reached operating temperature.

Can you describe the frequency and under what conditions is the pump turning on.

 

Remove the filter to it and clean it, a dirty filter can make it nosier.

 

spike i will look at the filter later,


other then that i have never heard the thing run before. and when i did hear it run it was for about 5 seconds and then not again.

truck had its 60k tune up at 50k so im sure its not dirty plugs or otherwise.

 

this sounds similar to what i am hearing in mine. i posted details in this thread:

https://landroverforums.com/forum/sh...t=20859&page=2

if it is this, where is this pump filter? disco 1

 

DI's do NOT have SAI. (secondary air injection)