JOB1963

I bought a stethoscope from autozone for like 10 bucks, you can run your engine and listen to the vacuum lines, especially around the joints where 2 or more come together, if you hear a loud hissing noise, you've pinpointed your leak. Of course it's not so easy to access all vacuum lines especially the line from the purge canister to the fuel tank, but if you're lucky, you'll find a leak in a location that has easy access. Auto parts stores sell vacuum line repair kits that come with 50 or 60 fittings, hopefully 1 of those will fit your needs. I bought 6' lengths of 5/32 & 7/32 (referred to as windshield wiper hose/vacuum hose) for bout .50cents a foot and replaced as many lines as possible, it's making a difference so far. Still have a few more to go.

JOB1963

I'm at a loss on explaining diagnosing the EGR. I did find a vacuum regulator(aka EGR solenoid) between the throttle body and EGR. This device has a cap on 1 end that retains a filter. When removed, the filter appears a small white end and the rest appears dirty, but it's the way it comes from manufacturer. I removed the whole device(EGR solenoid-2 8mm bolts, 2 vacuum lines & 1) 5 pin wire connection) rinsed the filter(it was clean) and wiped the area around the cap and filter. Since I broke a piece of the cap(old brittle plastic) I decided to apply a small bead of caulk around the edge where the cap meets the EGR Solenoid(aka vacuum regulator). Will reinstall after work today and report back on my findings.

JOB1963

<section id="PLATFORM_TL"></section>
<center></center>

<header class="header"> Not sure if I agree with all this but it's a start.


How an EGR Vacuum Solenoid Works

</header> <footer class="footer"> <footer class="AuthorProfileWrap footer"> By Don Bowman, eHow Contributor

</footer>
</footer>

• Print this article

Related Searches:

<section>

1. EGR (Exhaust Gas Recirculation)
   
   
   • The EGR is an exhaust gas recirculation device used for the purpose of lowering emissions. The purpose of the EGR is to allow a certain amount of exhaust to return and be mixed with the incoming fuel into the cylinders at cruising speed. This helps to cool the cylinders, allowing for a higher degree of ignition advance to burn more of the fuel. This makes the engine more efficient. If the EGR is not used, the ignition timing would have to be retarded somewhat so that detonation would not occur.
     
     
   Solenoid Switch
   
   
   • By increasing the ignition timing and allowing the fuel to have more time to burn, there is less unburned fuel reaching the catalytic converter, hence less emissions. The EGR cannot function at an idle, or it will cause a very rough running engine or stalling. It is meant to actuate at around a constant 2,000 rpm. This is accomplished through an EGR vacuum control solenoid. The EGR control solenoid may be an on-and-off type switch, or it may be a modulated-pulse width type. Either type has battery plus on one side, and the computer operates the solenoid by grounding the other side when it wants to turn the EGR on.
     
     
   • The EGR has four wires, three of which are to the computer so it can not only turn the vacuum on to the EGR but also monitor its position. Some EGRs use a trio of monitors on the top of the EGR to monitor and to operate the EGR electronically without the use of the vacuum solenoid.
     
     
   • The EGR is prone to getting plugged up with carbon over a period of time and should be inspected if a rough idle is occurring. It can be blocked up or stuck open. Before it is removed to inspect and clean or replace, check that it is getting a vacuum (if it this type) and that the rubber diaphragm inside it is not leaking, causing a vacuum leak. Check the EGR by squeezing the diaphragm up with your fingers to see if it moves.
     
     

</section>

JOB1963

Here is a link to a page that goes very deep explaining the functionality of an EGR and it's components: http://www.aces.edu/~parmega/efi/egr.txt
I hope this helps.

JOB1963

I just ran across an article where, the owner of the vehicle experienced similar symptoms as ours. He found that his fuel return line was obstructed. Once he straightened it out-it ran perfectly. I'm not quite sure how to test this but....I think I'll remove the return line from the throttle body and attempt to force some air in there from my compressor. It can't hurt right? 1st though, I suppose I'll look at the line to make sure it's not kinked, wouldn't want a fuel shower!

JOB1963

The caulk around the EGR filter cap wasn't exactly a good idea(That's where the EGR solenoid vents the unnecessary vacuum and should be able to breath) So I twisted the cap and the caulk seal was broken. It ran a bit better but still not 100%. When at idle, I noticed a steady stream/dribble of fuel from the bottom of the injectors. This could be caused by excess fuel due to a restricted return line. Will check after work today.