E39 counsel and advice sought.

The car is an '02 e39 with 63K on it. My SES light popped on this AM going to work. Conditions were cold (18F) but dry. I read the codes with my Peake and it referred me to Table 19, error codes F5 "Secondary air system flow too low, Cyl #1-3" and F6 "Secondary air system flow too low, Cyl #4-6". The thing is I changed both the secondary air pump and valve last spring about 8 K ago. I cannot imagine why they would go bad so soon. Could be the vacuum hose but I haven't checked that yet. I do get an occassional low level, high pitched squeal/sqeak on the cold sub-20F days. The sound comes in short bursts (for a second or so) and occurs shortly after engine warmup and then disappears a few mintues later. SAS pump noise?

My question: I reset the SES. I am thinking that if the problem is real, the light will relight sometime soon. This assumes that driving the car with a faulty secondary air system will not cause any significant damage to the car (it's just a damn pollution air pump, right?). If the SES relights, I'll troubleshoot this weekend.

Concur or non-concur with this course of action? Thanx!

Check the hoses.

A fault in the Secondary Air System won't affect operation of the engine, though it would cause a failure to pass emissions testing. The system only runs for up to two minutes on a cold start to inject additional O2 into the exhaust to speed up lighting off of the catalytic converters

E39 counsel and advice sought.

The car is an '02 e39 with 63K on it. My SES light popped on this AM going to work. Conditions were cold (18F) but dry. I read the codes with my Peake and it referred me to Table 19, error codes F5 "Secondary air system flow too low, Cyl #1-3" and F6 "Secondary air system flow too low, Cyl #4-6". The thing is I changed both the secondary air pump and valve last spring about 8 K ago. I cannot imagine why they would go bad so soon. Could be the vacuum hose but I haven't checked that yet. I do get an occassional low level, high pitched squeal/sqeak on the cold sub-20F days. The sound comes in short bursts (for a second or so) and occurs shortly after engine warmup and then disappears a few mintues later. SAS pump noise?

My question: I reset the SES. I am thinking that if the problem is real, the light will relight sometime soon. This assumes that driving the car with a faulty secondary air system will not cause any significant damage to the car (it's just a damn pollution air pump, right?). If the SES relights, I'll troubleshoot this weekend.

Concur or non-concur with this course of action? Thanx!

It won't do anything to your car to the extent of my knowledge unless you're trying to pass emissions. The SAS is designed to inject air from the outside (hence a pump to get the air) into the exhaust during start-up to reduce emissions.

What you're doing is fine, but I replaced mine when it started bitching too much.:shifty

For the short term, spray some lubricate up the pipe. It should quiet it down somewhat unless the pump mechanism is really worn out.

Edit: I'm not responsible if it screws your car up lolz; oops beat me to it the jlevie, tabbed browsing distracted me :)

Thanx, guys. I went for a short drive (6 m R/T) and the SES has not come back. I'll check the hoses this weekend.

Followup & conclusion.

I reset my SES but it came back on. I didn't want to change my pump and valve as they cost me $270 just last spring. So on to troubleshooting...

I inspected the secondary air system last weekend and could not find any obvious problems. I checked for water in the valve & pump, dirt/grit around the valve and pump and all hose connections. Nothing. I sprayed the valve and pump inlets with compressed air anyway. I checked the vacuum hose (~1/2" OD) and it looked fine but decided to change it anyway as I had the new hose from the previous pump replacement (I didn't replace it because it looked fine). On my year ('02), the hose is only a 5" piece between a plastic pipe and the valve. Upon removing the old hose, I noticed some hairline cracking where the hose bends to fit. This didn't seem to be enough to cause an SES fault but I changed it anyway. Voila! The problem is fixed and the SES lamp has stayed off (even in 4 deg cold). :alright

Morale of this story: Check the vacuum hose and replace it, even if it looks good as this is a $4 part and the pump and valve are much more expensive.

Hope this experience helps someone with a secondary air system fault. Thanx for all the help!

Having similar problem here in Cold weather in Edmonton, it has been -30°C here and even lower for nearly a week now.

Would you be able to take a picture of the hose you're talking about and where the cracking occured?

I had been getting equivalent codes from my car using Peake tool as well. Checked and quickly saw [as well as heard "whoosh"] where plastic line from SA pump to valve had once again failed.

Just Changed out valve and hose to SA pump this morning before heading into work. :)

I have 160K on this touring and the valve and heavily taped up hose looked to be original.

The valve comes off easily [two 10mm copper / bronze lock nuts] and of course ... the end of the vacuum hose broke off with the old valve [bonded to male inlet on valve]. Easy fix .... on the M52TU I6 motors there is some slack in the vacuum hose coming forward to the valve. Clean up the end of the line [make a note to buy some more to replace later] and connect to new valve. Use new gasket and you are also OK to re-use old copper locking nuts. Vacuum hoses typically brake on the end where they have to be pressed over a pipe / tube. Make sure you check further up the line as heat / dry-rot will also cause the cracking the OP mentions. You can get vacuum hose at any auto parts store ... bring an old piece with you.

Based on location .. I am sure the ~$25 plastic hose from the SA pump to the valve will fail again in short order.

I have the same codes. I need to get the car in my garage to take a look at them. Kinda annoying....