New injectors...wow, what a difference

And here I thought my engine was running fairly well; just a little rough edge. Boy, was I pleasantly surprised by the huge improvement in smoothness from replacing the ancient steelies with new. I've never heard it sound so good either.

 

78K miles and the car was enshrined in the garage for four years by the PO's wife after he died.

 

On our late QVs with the snap-ring style bushings, it's a piece of cake. Pulling the plastic bushings is the harder part of the job; you need to make up a "puller". If your bushing seals are good, you can get away with just popping the injectors alone and pressing the new ones in with new donut o-rings...but eventually the old bushing seals will get hard fail and cause a vacuum leak.

 

That's next on the agenda. I'm trying to find an indie with a gas analyzer that isn't terrified to touch an F-car. I had it set pretty lean manually and the idle didn't change with the new injectors so hopefully the new smoothness won't have to be adjusted away.

 

Injectors are Bosch PN 0 437 502 047; verify that it's same for the '84 QV; I'm 99.9999% certain it is. That injector # was used on a lot of Euro cars in the 80s. I bought them from AutoPartsWarehouse.com. Use Google Shopping to find the best current price. Several places sell them for under $30 ea. The o-rings (two sizes needed) are from T Rutledge. I should have replaced the grungy old snap-rings for the bushings with new too.

I did the work myself....about 4 hours once I figured out how to jury-rig a puller for the bushings using a 4 inch long 10/32 machine screw, some fender washers and a PVC pipe bushing. As usual for 308, the hard part is working mostly by feel on the front bank. You'll have to remove the throttle body to get to the rear bank 2 & 3. As I said, if you trust your bushing seals for a few more years, you can cheat by popping out the injectors only in no time at all, but at some point those 27 year-old o-ring seals will fail.

 

Since new injectors are under $30 ea., I saw no point in messing with the 27 year-old original injectors. No local shop (not even the "certified" Bosch Center) had a working injector cleaning/test set-up and I wasn't going to do a DIY solvent pump rig for a one-time job. The old steel bodies are certainly pitted inside from moisture and no solvent cleaning will restore the precision of the seats and angles. Periodic cleaning may be a good practice for the new ones.

Your VW puller will pop the injector out, but not the plastic bushing, For that you need to assemble something that fits through the bore of the bushing and catches its lip from beneath. Its got to be something that cannot drop through! I used a 10-32 x 4" lg round head screw w/nut & fender washer, a 3/4 PVC pipe bushing, and a 1 x 3/4 hardwood block as a non-marring fulcrum sitting on the manifold for the lever (a open-end wrench). They come out easy with a little leverage once you get a good grip. I doused mine heavily with WD40 a couple days before; I think it helped.