Thanks for the great documentation on installing a relay across the OPS on your website. I have also used your experience with the PMD cooler under the bumper and it works great - after looking at a number of other options on placement I think you have found the best.


I have recently noticed (once) on my 99-6.5 that the lift pump did not come on (pump noise) at glow cycle startup and I got a service engine light. I thought it odd, but don't have the equipement to read the codes so I disconnected the power to reset the computer and tried it again. It worked fine and no engine service light. It continues to work OK, but the seed has been planted in my mind.


I figure I should install a relay and have printed off your instructions and read you Feb 2004 posts on the subject, but have a couple of questions before I start into the job.


1) What type of relay did you use and where did you get it? Are there any specific specs for this type of relay?


2) I presume the OPS is in the engive "V" and the manifold needs to come off to get at the wires - is this true or can it be reached from the back near the fuel filter? Would you have any pics of this area?


3) The first time you do anything you do things you would not do again - are there any other helpful hints to make this a simple task for the first timer?


Thanks for sharing your experiences.

The OPS is behind the fuel filter to the rear driver's side. A 30 amp hd auxillary relay works for me.

The relay is a general purpose 30 amp. auto type relay that any auto store should have. If not I get mine from Bully Dog in Ohio 6 at a time. I get 6 not because they fail but because I use them for headlight controls while towing, controling my propane system, and all sorts of things. Its gotten to the point I can't remember what each one does when I crawl under the dash or hood. These are double pole single through relays but you will only be using the normaly open side.


I have just added a picture on my site that shows te relay mounting and shows where I cut into the harness for the mode.


It's a pertty straight forward installation that I would not change.


If your fuel pump failed to come on during the glow plug cycle I would look at the fuel pump relay already in your truck on the fuse panel under the hood. It is that relay that closes during the glow plug cycle to supply the pump with voltage.


Good Luck








Edited by: HowieE

I located the OPS last night and it is easily accessable at the fuel filter.


Thanks for the feedback and adding the photo.

HowieE:


I have located an 30amp aux relay and am going hook it up tonight, but have a qusetion about relay switches.


I would like to check my fuel pump relay but am not sure how it can be tested to see if it is reliable.


I have not worked with switches much and (exposing my ignorance of the issue) I am wondering: Can you "check" a relay switch? Can it be checked with a digital multimeter? Is it simple continutity or is it amps/voltage going in and out? Is it possible for a relay problem to be intermittent or will they just fail? If an intermittent or slow failure is possible will it show up in a multimeter test?


Any insights as to the testing proceedure will be appreciated!