Has Anyone Had Luck Replacing the Secondary Air Pump w/ An Aftermarket Unit?

Has anyone had any luck or experience replacing the secondary air pump on their 4.0 V6 with an aftermarket unit? Got the dreaded P0418 code unfortunately.

 

Have you verified you have power and ground at the pump when it is commanded on?

 

No I haven’t yet.

 

Nothing useful to add but I’m wondering since our trucks are the same builds how many miles do you currently have and have you done any pm to the media like replacement foam or uni delete?

Anybody know the typical lifespan of these units when the media is kept in good condition?

Trying to prepare myself if this happens to me. Truck is currently sitting at 103k.

 

Have about 152,000km, so about 93-94k. I have replaced the foam with a filter, about 4-5 years ago.

 

Removed the cover as soon as I got, spun the fan, nothing lodged in there. Connected a 12v source, it flinched and assumed it was dead. Started her back up, pump is not running, assuming its dead, cleared the code, shut the truck off and I hear the pump going.

Started the truck again, shut it off and it’s working lol! Did this several times within 30mins, so far so good and no check engine light lol!

 

Probably the brushes are shot in the motor but maybe you will get lucky and it will work for awhile yet.

 

if its working again its cheaper to bypass it. I did this and it reads fine on emmissions.

https://hewitt-tech.com/product/secondary-air-injection-system-bypass-kit-gen-2-plug-play/

 

And it stopped working again lol!

 

You guys think it could be the pump or relay??

 

@LP3 replaced his pump with an Amazon chineseium unit two years ago and it's still running OK. OEM pump had the brushes go:
https://www.tacomaworld.com/posts/24558804
https://www.tacomaworld.com/posts/24586481

 

@LP3 What codes were you getting prior?

 

How do you guys keep track of these things. You guys are amazing. I didn't u even remember doing this air pump. Seriously..
As for the codes I'm sorry I don't remember. Now as for the air pump it's going strong never a problem since and my complete engine bay is kept at a light tan silt covered. It's it's dusty muddy by the pump all summer so it's a good one....

 

Run the Hewitt bypass

 

It’s been done lol!

 

Nah, HP Tuners is the way!!

 

Hi all new member here,
Both my kids are driving Tacos, son bought a 2013 4 years ago and gave it to his sister when we bought him a 2022.
In Dec. 2022 my 2013 (117k mi) VR6 threw a P0418. I checked the pump fan, foam intact, read some forum, cleared the CEL code and it went for a month before it threw the code again.
Symptoms: CEL and Trac light on, no engine performance deficiency. Other probably unrelated factors: Gas cap on tight, having heater fan switch electrical problems (won't come on 1-3. only on in position 4 high fan{{did fix this as well in December with repositioning electrical connector found in other forum/YouTube problem solving located on inside firewall passenger side [[problem now recurrent and not responding to repositioning fix. no fan 1-3 switch settings]]}}
Outside temp at start up (when CEL on) 30-35* F. No fan activation at start up nor shut off, multiple attempts.

This time I took it apart down to removing the tops of the valves. Findings:
1. pump fan intact bench tested with a 12v and runs quite well. Put on the aftermarket air filter and removed the foam. No noticeable damage to wiring harnesses nor connectors. (Did not check the ground lead on the wire from the ECU/relay)
2. hoses intact and when sequentially dissembling them from the pump back, I started to get increasing condensation inside the hose at then end of the hose from the pump where is connects with the 1st coupler (plastic) that attaches to the front of the engine. 2nd hose more condensation/water now (drips) at connection to 2nd coupler (metal). 3rd hose to valves same as 2nd, water drips.
3. Valves see photos
A. Both valves had carbon build up equally photo 1 & 3. Front valve on right photo 1
B. Both reed valves open and clear in photos 2 & 4.
C. Valves/Solenoids. both carbon build up both freely rotating and open with a screw driver. (Tried to test with DC v but unable to figure which connector pins activated solenoids to open valves) Photo 3.
D. bottom housing of valve assemble (Sorry no photo) Both had carbon build up as with the reed valves and solenoid valves, BUT FORWARD VALVE housing was wet and rear valve was dry.
.


Info reviewed:
1. read many forum entries mostly on the 2012 Taco which seems to have been a worse nightmare involving limp mode of vehicle and P2442? codes. Noted possible significant difference of solenoid valve construction from other forum photos between 2012-2013. (2012 had internal rubber components of valves that were irreparably destroyed likely from overheating {? valves stuck open?}. 2013 valve construction different? metal valves no visible rubber parts, no damage noticeable on my valves, valves fully closed on removal.
2. significant discrepancy as to when the secondary pump is to be activated ( coinciding with solenoid valve opening under closed loop activation) under normal conditions. Outside Temperature related factors?? Should the pump and valve be activated at start up under 40*F where freezing may be occurring for any water/condensation in pump or inside valve where valve may not open (no moisture noted on my upper valve assemblies that would indicate no valve opening, however moisture noted in lower valve housing on forward valve AND moisture in hoses between pump and valves.
I called Toyota of Puyallup (locally) and spoke with parts to see if they had a valve combo for replacement (just in case) and discussed issue with rep who at least spoke with me and I asked if he could at least get an answer from a technician to resolve the "Normal function Toyota spec for temp) as to when the fan & system should be activated in relation to outside temperature. The parts rep said he would ask a tech and get back with me (that was 2 days ago).

Actions taken:
1. removed fan, inspected and bench tested for operation (applied dielectric lube to connector on reassembly.
2. removed and inspected hoses and clamps and dried water/condensation.
3. removed top of valves inspected and cleaned reed valves and upper valve housing. Re-assembled valve .
4. Re assembled hose and pump.
5. Cleared codes 3 x and restarted engine 3x and all P0418 codes cleared. 2 short drives and codes remain cleared.

My Questions:
1. A good general question would be what are all variable conditions then the system should be in operation cold start and warm start and shut down. My understanding is that this system should NOT be in operation during normal running of engine and should be in open loop with valves closed and fan off, it is only smog related at start up and shut down. The ECU and the O2 sensors should be regulating the fuel delivery for smog and engine efficiency.
2. Another general question I have: if the fan is only coming on for approx 30 seconds at start up and 5 seconds as shut down, Is that enough operation time to clear moisture from atmospheric humidity that would most likely explain source of water pre valves?
3. Also, moisture in the lower housing of forward valve assembly and not 2nd. Forward valve connecting to passenger side exhaust manifold and rear valve to driver side manifold.
4. Where is the relay that activates this system and how is it tested.
5. How can I bench test the valve assembly solenoid movement.
6. P0418 code is a secondary air pump code bank A code. ?controlled by 89581A? there a way to test the AIC function in its control of the secondary air injection pump and valves?
DRIVER, AIR INJECTION CONTROL
Part Number: 8958160010
Supersession(s): 89581-60010

7. Is there a way to program the ECU to come on and stay on longer to help clear moisture accumulation of the system?

Thanks for any/all input.




Prediction:
CEL will stay off for a while but likely to come back on and will need to trouble shoot the electronic control of the pump by the AIC; electronic control and function of the valve solenoids;

 

Toyota had a recall to re flash the ECU to make the pumps/valves cycle at random times.

 

Please check if the Tacomas had the ECU re flash. The 2nd gen tundras have the same system and same problems.

If you re flash the ECU, you will not be able to do the bypass mod.

My tundra has been running the home made bypass version for the last 10 years.

I keep getting recall notices to have my ECU re flashed by the dealer. I toss them in the trash.

 

This is the version I used. Cost about $15.

https://drive.google.com/drive/fold...JTjVWa1U?resourcekey=0-GEXdlmQrR0ElvRboXWKwBQ