2004 Discovery repair advice needed

[SexyExy]

We are getting ready to sell my daughters 2004 Disco. It has served her well and gotten her through high school and college and never left her stranded.....pretty incredible if you think about it. Seven years of service with nothing major other than scheduled maintenance. But now she has graduated and has a job that will require commuting...the Disco just doesn't make sense when she needs something that gets 30 plus mpg.

Last week a check engine light came on and we found that the Secondary Air Pump hose has melted a hole in it. Apparently this is caused by a Diverter valve that has failed or is not functioning due to vacuum leaks, etc....hot exhaust gases go the wrong way and melt the plastic portion of the hose. Has anybody ever replaced the Secondary Air Pump hose on a Disco II? I'm trying to figure out what this entails and the labor costs to do this. The Diverter valve may also need to be replaced if it has failed. I took a quick look at the hose routing but can't tell where it connects on the firewall side of the truck.

Any input or experience with this repair would be appreciated.

 

[DiscoDavis]

We are getting ready to sell my daughters 2004 Disco. It has served her well and gotten her through high school and college and never left her stranded.....pretty incredible if you think about it. Seven years of service with nothing major other than scheduled maintenance. But now she has graduated and has a job that will require commuting...the Disco just doesn't make sense when she needs something that gets 30 plus mpg.

Last week a check engine light came on and we found that the Secondary Air Pump hose has melted a hole in it. Apparently this is caused by a Diverter valve that has failed or is not functioning due to vacuum leaks, etc....hot exhaust gases go the wrong way and melt the plastic portion of the hose. Has anybody ever replaced the Secondary Air Pump hose on a Disco II? I'm trying to figure out what this entails and the labor costs to do this. The Diverter valve may also need to be replaced if it has failed. I took a quick look at the hose routing but can't tell where it connects on the firewall side of the truck.

Any input or experience with this repair would be appreciated.

No idea what those things even do! Quick google-**** brings this up. Appears relatively external to other components, DIY seems possible.

http://www.roverparts.com/resources/videos/secondary-air-engine/

 

[SexyExy]

No idea what those things even do! Quick google-**** brings this up. Appears relatively external to other components, DIY seems possible.

http://www.roverparts.com/resources/videos/secondary-air-engine/

I looked at that video this weekend when I was trying to do some research on the issue....the part he is showing is (to me at least) an electric powered smog pump that injects air into the system on start up to help fire off the catalytic converters (at least this is my understanding). The hose in question goes into that general direction but disappears behind the motor against the firewall. I'd prefer to have somebody fix it since that location is going to kill my low back due to previous injury.

If the diverter valve is bad, that's close to $300 and the hose is around $100. It's the cost of labor that scares me :Wow1:

This is the hose with the hole in it:

http://www.roverparts.com/Parts/WAH100150G

 

[Longtallsally]

This makes me feel very fortunate that I now have a non SAI D2. I had no issues with it in my first, but was always scared of it.

Replacing the part should not be hard and if you are selling, I'd buy it used. Now, finding all the possible vacuum leaks and confirming all the parts are functioning correctly could cost the same as the value of the vehicle real quick if done at a shop.

Me personally, I'd find a donor SAI vehicle, and start scavenging everything, or find someone's parting one out and get all the components you can. If you have the RAVE manual (it's free if you don't) you can study the system and start from there. In theory it's it's a couple valves, a pump and a bunch of hoses.

If you don't want that headache, I'd sell as is and take the hit on price. However, being in Kalifornistan, I'm not sure you can even sell stuff as is. Once again, couldn't be more glad to be gone from that place. Best of luck.

 

[SexyExy]

This makes me feel very fortunate that I now have a non SAI D2. I had no issues with it in my first, but was always scared of it.

Replacing the part should not be hard and if you are selling, I’d buy it used. Now, finding all the possible vacuum leaks and confirming all the parts are functioning correctly could cost the same as the value of the vehicle real quick if done at a shop.

Me personally, I’d find a donor SAI vehicle, and start scavenging everything, or find someone’s parting one out and get all the components you can. If you have the RAVE manual (it’s free if you don’t) you can study the system and start from there. In theory it’s it’s a couple valves, a pump and a bunch of hoses.

If you don’t want that headache, I’d sell as is and take the hit on price. However, being in Kalifornistan, I’m not sure you can even sell stuff as is. Once again, couldn’t be more glad to be gone from that place. Best of luck.

You're right about being in Cali and having to smog before being able to re-register it under the new owners name. I guess I might find somebody that will buy it as is, but I'm very happy with this truck and the service it provided my young daughter. Other than brake pads and basic maintenance, this is the first real issue with the truck. It was a great truck for a new young driver and I'm hoping to find somebody that I know that can buy it as a learning car for another young driver. Great visibility, you sit up high, anti lock brakes and a ton of metal surrounding them. The truck is set up nicely with powder coated to match ARB bumper, ARB side steps, ARB lift, ARB shocks and steering stabilizer. It also runs LT265/75/16 Hankook all terrains so it looks great and rides better than it did with the stock 18" rims. Biggest real issue is the valve cover leaks oil and the head liner has a couple of spots that is separating off the edge. The headliner was an easy fix with thumb tacks painted to match. The valve cover is going to be the future owners issue, lol.

I've taken your advice and ordered a used secondary air pump, new secondary air hose and once we figure out if it is a vacuum leak or defective diverter valve, we'll get that ordered too if needed. I've been looking for a donor vehicle as I've seen them in the past....but when you need one, they're never available. Thanks for the input and I've been studying the secondary air system and really, there isn't much to it unless you can't find the vacuum leak easily. I should have some answers in about a week when the parts start coming in.

 

[Longtallsally]

I'm lucky to have a parts truck that has SAI that worked properly. If you need any parts let me know. I didn't mention previously as it didn't seem like you wanted to do the work- sorry.

Your logic sounds good and as long as you have some patience, you can probably sort it out.

 

[SexyExy]

I'm lucky to have a parts truck that has SAI that worked properly. If you need any parts let me know. I didn't mention previously as it didn't seem like you wanted to do the work- sorry.

Your logic sounds good and as long as you have some patience, you can probably sort it out.

Thanks and I'll let you know if I need any parts.....right now the only unknown is if the diverter valves are defective or if it's a vacuum leak causing them to not operate. Leaving for a trip so I won't have any answers until next week.

 

[kcabpilot]

The hose connects to the metal tube on passenger side that basically just Tee’s into the longer one behind the plenum which then connects to the valves on each side. Make sure the little vacuum lines that run from the control solenoid to each valve are hooked up and not broken. It’s not all that complicated, better than running a belt driven smog pump full time. It’s only needed for a minute or two on cold starts.

 

[SexyExy]

Just wanted to bring an update on my kids Disco. The SAI system was kicking codes that was not allowing it to pass smog. The key word here is system, it appears if on part fails it can take out other parts if not addressed in a timely matter (example: don't keep driving it if the check engine light code is on, lol). I replaced the electric air injection pump (was making a lot noise), both air control valves and the air injection vacuum control solenoid. I also put a new fuel cap on for good measure since one of the codes was regarding the evap. Once all parts were done and the computer cleared, it took less than a 25 mile drive cycle to set all the monitors. Passed California smog no problem.

The RAVE manual is very easy to follow and once I started really looking at the diagrams and started following the hoses and tubes under the hood it wasn't so daunting. Really not a very complicated system once you understand the process and what it is trying to achieve.

Now its going up for sale.....I hope my daughters new economy car is as reliable as her old Disco. Looking back she drove it for 8 years and almost 65,000 miles and it never left her stranded. Thank you Land Rover for keeping my baby girl safe!!