Main IndexAuto Repair Home Search Posts SEARCH
POSTS
Who's Online WHO'S
ONLINE
Log in LOG
IN









p1494 auxilliary emission controles


  Email This Post

Auto Repair Home : Automotive Repair : Engine Fault Codes :


scotchy
Novice

Jan 27, 2012, 4:24 PM

Post #1 of 3 (401 views)
Shortcut
p1494 auxilliary emission controles Login - Sign Up

  My vehicle is a 1999 dodge 2500 club cab with the v-10 engine. I plugged my $100 dollor scanner in and retrieved the p1494 code. My tool descibed this as, leak detection pump switch or mechanical fault. Furture search revieled, manufacturers controlled auxilliary emission controls. Can anyone help me with an avenue to repair. Thanks


Discretesignals
Veteran / Moderator


Jan 27, 2012, 6:49 PM

Post #2 of 3 (362 views)
Shortcut
Re: p1494 auxilliary emission controles [In reply to] Login - Sign Up

It's pretty difficult to figure that one out unless you have an enhanced scan tool that can enable the LDP test while you watch the switch state of the reed switch to see if it changes states.

Basically the LDP (Leak detection pump) is used to check for leaks in the EVAP system. The pump uses engine vacuum and a solenoid to control a diaphram pump. The pump shaft itself is attached to a reed switch that opens and closes as the diaphram moves. The pump actually pressurizes the EVAP system to check for leaks by monitoring the time the switch opens and closes. When the switch fails the engine computer can't run the test because it doesn't know what position the pump is in or if it is even working. The reed switch is inside the LDP.

I am not going to say the LDP is the problem, but most of the time it is. About all you can do is check the vacuum hose to be sure there is vacuum at the pump and inspect the electrical connector on the solenoid unless you can get hold of a scan tool and wiring schematic for the EVAP system.













Since we volunteer our time and knowledge, we ask for you to please follow up on your threads when a problem is resolved.

(This post was edited by Discretesignals on Jan 27, 2012, 6:59 PM)


scotchy
Novice

Jan 29, 2012, 1:24 PM

Post #3 of 3 (330 views)
Shortcut
Re: p1494 auxilliary emission controles [In reply to] Login - Sign Up

   Once again you've been able to lead me to my problem. I inspected the vacuum system and found the vac. hose on the bottom of the throttle body had dropped off. great job.




CarJunky Sponsors
p1494 auxilliary emission controles



  Email This Post
 
 



Latest Forum Post
Hi, My 1999 Pontiac Grand Am GT 3.2L engine car will not start up smoothly and ...
How is it that a smaller engine can produce more power? For example, the Skoda...
We have a 99 chevy silverado with a 5.3 vortec engine, we put it in 4 WD low and...
Hello. I have been having a problem with my 1994 Cutlass Supreme ( 40,000 miles)...

Feed Button




Automotive Forum Categories
Automotive Repair | Car Troubleshooting | Engine Troubleshooting | Engine Fault Codes | Transmission Problems | Automotive Wiring and Electrical | Car Stereo Repair Advice | Car and Engine Noises | Heating or AC Issues | Tricks of the Trade | Automotive World | General Discussions | Antique Car Talk | Car Shows and Events | The Bargin Bin | Motor Vehicle Inspection | Auto Insurance, Financing, Leases, Warranties | Car Care Tips | Traffic Tickets | Gasoline, Motor Oils, Concept Cars and Engines | Automotive News Discussions | Truck Repair Help and Advice | Truck Troubleshooting | Motorcycles and ATVs Help and Advice | Board FAQ's | Car Forum Posts - Sitemap


Search for (options)