How-To: Repair a Air Injection Pump

[Audiomechanic]

Does your Beetle have a check engine light? Does you Beetle make a loud screaching sound right after it'scold started? Does you Beetle have a "Secondary Air Insuficient Flow" code? Well,you might have an injection pump with broken rivets! The good news: it's very easy to fix and takes about an hour or less. The bad news is, it's expensive (about 2 bucks for screws and then 1000 dollars to me for writing this amazing writeup! ).

Ok, start by removing the plastic shield on the top of the engine. There's screws holding it on (2 in the front under little covers, and one straight back from the oil fill cap). Onceyou get it off, look down the front of the engine, just under the intake manifold and you'll see the black plastic pump:


Next, remove the hose from the pump to the air box. Then disconnect the pump end of the other (smaller) hose. Next, remove the small bracket on the far right side of the intake manifold that has the plastic clamps for the 2 air injection hoses and the coolant hose below. Not too bad to get off.

The pump is mounted to a bracket which is held to the intake manifold by 3 bolts. They are allen heads. Remove them:




The pump's bracket must come off to get the pump out. So you'll have to rotate the pump around in the small space it's in to get to the 3 bolt holding the pump to the bracket. It's very tight but the pump will rotate with a little manipulation of the coolant and AC hoses.



Next, disconnect the electrical connection on the back of the pump. You'll need a flat head screw driver to GENTLY pry the small tab on the end under the connector comes loose. The remove the bracket and then manipulate the pump out of the engine bay. It's tight, but it'll come.

The rivets that hold the pump together are very cheap aluminum rivets. Apparently, they break. Here's what the bottom of the pump looked like and why it threw a code:


And the broken rivets:


These are the screws you'll need (get 6 of them and make sure they come with nuts):


Next, take a drill and bit that's about the same size as the heads of the rivets and LIGHTLY drill them until the heads of the rivets break off:



Then, gently remove the outter layer of the pump (the cap with the air hose connection that came from the airbox) bringing the rivets out with it. Tap the rivets out of the pump, replace the cap onto the pump in the same position it was, and then install the screws:



Finally, reinstall the pump in the reverse order you removed it. Here's the pump installed with the new screws:


THAT'S IT!

[2004NBTURBOS]

Well done DIY. The pics and the directions make it uber easy. A lot of people will benefit from this. Thank you, Thank you.

[Audiomechanic]

Well thank YOU for the compliment!

This might be good preventative maintenance as well since, according to my mechanic at Herr Schmidt's, the rivets tend to give out on the bottom of the pump and then they can take in water and lock up. No bueno.

[angelworks]

I think you may have saved me from buying a new pump and solved my eternal check engine light.

You = awesome!

[scarabY2k]

Originally Posted by 2004NBTURBOS

Well done DIY. The pics and the directions make it uber easy. A lot of people will benefit from this. Thank you, Thank you.

Agreed Many, including myself are going to benefit from this DIY. The dealer quoted me around 400.00 to do the exact thing you did. Man I can do this, no problem. Thanks again for a great write up

[Audiomechanic]

Thank you all for the kind words and y'all are certainly welcome. I have benefited from wiretups myself so I try to do them when I can.

I can't take the credit for the info though because it was my fabulous mechanic at my fabulous shop that told me I could do it and how. I'm just passin on the info.

Also: while you're under there, check your vaccuum lines. One of them on our Beetle had come off the intake manifold and that's what caused the turbo code and power loss.

Cheers and peace!

[mat3833]

does anyone kno the part number for the mount?? and by mount i mean the rubber-ish one. when i got in my accident that mount broke and the damn mechanic never replaced it. im debating using some shoe-goo or JB-weld to try and fix it.

PS. ill b doing the screw job soon. that high-pitched whining has been driving me freaking insane.

Matt

[scarabY2k]

Originally Posted by mat3833

does anyone kno the part number for the mount?? and by mount i mean the rubber-ish one. when i got in my accident that mount broke and the damn mechanic never replaced it. im debating using some shoe-goo or JB-weld to try and fix it.

PS. ill b doing the screw job soon. that high-pitched whining has been driving me freaking insane.

Matt

You know, you brought up sometning...JB Weld. I was wondering if a bead of a superior quality sealant was applied toe the SAI before the machine screws were torqued down, would this give the SAI a better seal. I'm assuming it had no original seal and torquing the 2 halves of the SAI will suffice.

[Audiomechanic]

Mine seals fine with no sealent. Look at this picture. You can see the soft rubber gasket coming out of the gap. There are two gaskets, one on the outer cover and one on the inner cover. The gasket coming out of the gap here is the inner cover gasket.

[03nb1.8t]

thanks for the post! i got encouraged to check mine as i've been experiencing loud whining noise on cold start up and that check engine light that's been on forever. anyhow, when i pulled mine off the casing is not held by rivets. the casing is one piece! no way to open it. would this mean i have to buy the whole pump? i appreciate any input...

[Audiomechanic]

I would say, unless you can find a way to rig yours, you'll have to replace it. When my mechanic was explaining the pump repair to me, I saw a pump that looked just like yours sitting on the counter. It came out of a Jetta and the mechanic said there's not much you can do with the non-riveted pumps except replace them.

Shoot, try to find the leak and then use some serious heavy duty epoxy to seal it up. Couldn't hurt to try it!

[marvins_dad]

I keep hearing the scream sound occasionally in my TDI - I'll have to see if I have one of those 2nd-ary do-hickies.

Great write-up!

[03nb1.8t]

[QUOTE=Audiomechanic;604306]I would say, unless you can find a way to rig yours, you'll have to replace it. When my mechanic was explaining the pump repair to me, I saw a pump that looked just like yours sitting on the counter. It came out of a Jetta and the mechanic said there's not much you can do with the non-riveted pumps except replace them.

thanks for responding! well, when i pull this unit i noticed that 2 of the three mounting rubber pieces are broke. since it's non-riveted i decided to re-install it back for now and replace the mounts($15 a piece at the stealership). for some reason the squealing is gone and have not come back since. i reset the engine light but that came back. i would have to have it checked to see what code is throwing it off now...

[Audiomechanic]

When you first cold start the car, place your hand around the edges of the pump and underneath it to feel for air rushing out. Do the same for all 4 hose connections for the secondary air system (the airbox, both pump connections, and where the outlet hose meets the thingie towards the back of the engine compartment). If you feel air around the pump, try some epoxy on it to seal it. Couldn't hurt. Id rather pay 5 bucks for some epoxy before I paid 400 for a new pump.

Also check all of your vaccuum lines on the top of the engine. When I repaired our pump, the squealing went away but the check engine light did not. Pulled the same code too. Turned out, one of the vaccuum lines had come off the intake manifold and therefore was causing the valve at the back (where the outlet hose from the pump goes) to not actuate, making the computer think there was still a problem with the pump when there wasn't.

[Downtown Turbo]

I just tackled this yesterday and it solved all the issues I was having (EGR pump honking and engaging even after the motor was warmed up while I was driving!). Thanks for the tut!

List of tools you will need

Hardware:

The perfect size of drill bit to start with is 11/64, then switch to a 9/64 bit to finish. Otherwise if you use a larger bit like 3/16 like I did you will have issues getting the remainder of the rivets out as the burrs will dig in as you pull them through the other end with pliers and the head will break off forcing you to use a screwdriver or something to press the busted rivet through.

I reccomend using #8-32x2 machine screws instead of the #6-32 x 1-1/2. The #6 screws have a diameter that is a bit less than the size of the holes left when the rivets are removed and the #8 are a bit snugger. Also try to find machine screws with robertson drive ends as they will be easier to tighten as the flat head will tend to slide out easier)

Also if you go with the 2" long screws then you can use nylon locknuts. With the 1-1/2" screws there is not enough thread to make it to the end of the nut that actually has the nylon inserts. It does look more oem with the 1-1/2" screws though (you could use some threadlocker if you took this route) but I would not want to do this job again if the nuts loosened off as it is a PITA to get the pump out (I left the bracket on). I reversed the screws so the long end of the screws don't stick out towards the hose end.

Tools:

- Ratchet (3/8" drive - don't use a 1/4" - too wimpy)

- Adjustable or fixed (9mm) wrench (for final tightening of the machine screw nuts)

- #5, #6 hex sockets (#5 for the EGR bracket bolts and the #6 for the 3 bolts that are holding the bracket to the intake manifold)

- 10mm socket for the single bolt on top of bracket with the easy-tighten clips that hold one of the pump hoses (bigger one) and rad hose

- 9mm socket for the machine screw nuts to get them most of the way down until you have to switch to the wrench as the socket will not fit between the nuts and the pump housing for final tightening

- Robertson stubby to match to match the machine screws

[Audiomechanic]

Always room for improvement. Good info!

[Downtown Turbo]

One item you may want to purchase at the dealer is those 3 rubber vibration mounts that hold the pump to the bracket. They tend to break (2 of mine did and my pump was only held on by one lol) so it would be a good time to replace them. Otherwise you can source some bolts with matching diameter and thread (I used MK3 VR6 EGR pump bolts:gifted from a friend) but then you would have to buy some rubber washers (I bought some 3/16 x 1/2 x 1/16 from Lowes: pack of 2) and insert those between the bracket and pump side to make up the slack space. The issue here with this workaround is that you only get dampening in one plane of motion. The stock mounts move in all 3 planes and would absorb alot more vibration.

[sb_beetle]

Last time I was in the shop (alternator) they also said my pump was on the way out. They wanted $500+ to do it and said it would be less as they were already in the area in terms of labor. I hadn't had any issues (CEL) so I said no. Sure enough I drive off the lot and... voila... CEL. I ran a VAG scan and came up with incorrect flow. What are the chances of them mentioning it and then getting a light? Pretty good at my dealer I guess! While they have been good about warranty and recall issues I'm beginning to be wary. After looking at the DIY fix I decided to go out and check if I had rivets. Unfortunately I didn't :-( But, I did find that the tech conventienly managed to leave the unit disconnected 8-0! I can't believe I've been running that way for the past 3 months and didn't see it sooner. Cleared the CEL and took it for a test drive and no more light GREAT WRITE-UP and PICTURES!!!

[simonsi]

Originally Posted by sb_beetle

...and said it would be less as they were already in the area in terms of labor...

Oh sure, you would save all of five seconds popping the hood a second time...they have nothing else in common!

Sounds like you dodged a con bullet - well done!!!

[Basher]

Great how-to but I'd like to add that it would be good to use self-locking nuts or some locking fluid cause it's quite a vibrating environment. I also suggest A2 or A4 stainless fastners instead off zinc plated parts.