Alternative Bosch injectors?

[JimNap]

Hello everyone, I'm a newb to this forum and I have to say it seems a lot friendly and more informative than Rennlist thus far!

The online Pelican purchasing is really nice as well. Anyway, I digress...

My car is an 85.2 944 N/A

I've had a recurring probelm where the car stumbles on idle especially when cold and from reading other threads, suspected the ISV/Idle Control Valve.

I got a new valve and started the replacement procedure, but in the course of removing the intake plenum, I discovered that my injector pintle caps were cracked - in 1 case severely. I removed them and sent them out for service. A day or so later I got a report back that 2 were not serviceable due to leaky pintle cap seals or something similar.

In the course of searching for new/used or reman injectors I began to discover posts here and elsewhere that the Bosch 0-280-150-159 injector was also a clsoe replacement for our 0-280-150-158 injector with specs varying only 2-3%, but at nearly half the cost (for new).

I then found this thread that seemed to improce on this line of thinking with metal pintle caps to prevent the cracking I and many others have seen:

Alternative Fuel Injectors

Only thing was, it was tests performed on Carrera.

I've used search, but could find nothing on attemtps to find alternative, better, and more economical options for 944's.

Any thoughts?

Jim N
1985.5 (B) 944 N/A

[Razorback1980]

Hey Jim,

Welcome to the forum...and yes we are friendly here. I am not sure about the Bosch replacement as I have not read anything about that. The only work I have ever had done on mine is I sent them out (witch hunter) to a place that serviced them and mapped them so I had four evenly matched injectors. The price was very cheap 60 dollars if I remember correctly. My theory on that was with evenly mapped injectors, I would get an even idle. I actually bought four extra injectors off ebay and sent the eight out and they picked the best four to rebuild and sent them back pretty quick.

As for an uneven idle; (I call it a hunting idle because it goes up and down looking for a place to settle), there are several reasons this can happen. The most common cause is a vacuum leak somewhere. While you have the intake off, replace all your vacuum lines, you'll be glad you did and it's really inexpensive to do that. Make sure each one has a good seal.

Sounds like you are on the right track.

[JimNap]

Originally Posted by Razorback1980

Hey Jim,

...

As for an uneven idle; (I call it a hunting idle because it goes up and down looking for a place to settle), there are several reasons this can happen. The most common cause is a vacuum leak somewhere. While you have the intake off, replace all your vacuum lines, you'll be glad you did and it's really inexpensive to do that. Make sure each one has a good seal.

Sounds like you are on the right track.

Thanks! I've already created a lengthy shopping list of vacuum hoses here at Pelican, including a new heater control valve that I read elsewhere that was recommended.

Also - I am getting oil residue in the throttle body. I read this comes from bad crankcase separator seals - I got those coming too.

Between the ISV, hoses, crankcase sep. seals, and new injectors - I'm still getting the feeling I'm forgetting soemthing. (I did plugs, cap & rotor & air filter a few weeks ago).

[Razorback1980]

Hopefully you ordered intake gaskets! Good call on the OA separator.

[choinga]

I've got 4 stock from a 87 951 (I think those will work with your car) that work great - just replaced them to put in 83#'rs w/ my Vitesse MAF.

If you're interested let me know...

[HondaDustR]

Originally Posted by JimNap

Also - I am getting oil residue in the throttle body. I read this comes from bad crankcase separator seals - I got those coming too.

The AOS seals are usually the first suspected culprit, but a vacuum leak anywhere on the crankcase can do it. Check your dipstick tube seals and balance shaft housing rear plug seals as well. Mine stopped sucking oil only once I replaced all of those (they were all leaking, esp. the balance shaft housing plug o-rings). Worn out piston rings can also do it.

Originally Posted by choinga

I've got 4 stock from a 87 951 (I think those will work with your car) that work great - just replaced them to put in 83#'rs w/ my Vitesse MAF.

If you're interested let me know...

I'm pretty sure the turbo injectors are different from the NA injectors and aren't really interchangable unless you need higher delivery injectors to support engine modifications, but correct me if I'm wrong.

[JimNap]

Originally Posted by HondaDustR

The AOS seals are usually the first suspected culprit, but a vacuum leak anywhere on the crankcase can do it. Check your dipstick tube seals and balance shaft housing rear plug seals as well.

Yeah, I've got the oil dipstick seal in the cart. But not the balance shaft housing rear plug.... yet! Is it difficult to change? I think you all know the Chiltons/Haynes manuals are useless and this is my first 2.5L surgery!

Originally Posted by HondaDustR

Mine stopped sucking oil only once I replaced all of those (they were all leaking, esp. the balance shaft housing plug o-rings). Worn out piston rings can also do it.

EEk! perish the thought! I need her to get me by for another year or two before I do a full resto-mod on her!


More details on removing/replacing the balance shaft housing seals/orings would be really nice, but since it isn't thread related, feel free to email me (anyone!):

jimnap at voyager. net

Thanks! I'm really loving this board so far!

Jim

[choinga]

Yeah, the Haynes is worthless. You should really grab the shop manuals in PDF format for more/better information:

http://www.texasblake.com/porsche/docs.html

[HondaDustR]

Originally Posted by JimNap

Yeah, I've got the oil dipstick seal in the cart. But not the balance shaft housing rear plug.... yet! Is it difficult to change? I think you all know the Chiltons/Haynes manuals are useless and this is my first 2.5L surgery!



EEk! perish the thought! I need her to get me by for another year or two before I do a full resto-mod on her!


More details on removing/replacing the balance shaft housing seals/orings would be really nice, but since it isn't thread related, feel free to email me (anyone!):

jimnap at voyager. net

Thanks! I'm really loving this board so far!

Jim

The balance shaft rear plug o-rings are a PITA, mostly because getting to them requires alot of work if you're not already in there for other things. It requires stripping all the pulleys and rollers from the front of the engine as you would do for a water pump job in order to get the rear cam belt cover off. It also requires removing the balance shaft front bearing/seal housings, which is a good chance to replace the shaft seals and o-rings there, which are prone to leaks. For the driver's side housing, you have to remove the intake manifold and fuel rail, which you're doing anyway, and then it's right there. The passenger side is not so easy. You have to dismount the power steering pump and exhaust manifolds and it's still kind of a tight fit, but can be done. From there, it's just bolts, cleaning the old sealant off, installing a new o-ring on the aluminum plug, sealing it up with anaerobic flange sealant, reinstallation (a little tricky, read the procedures below carefully), and then the marathon job of putting all the other stuff back together.

Here's the full details at clarks garage
http://www.clarks-garage.com/shop-manual/eng-14.htm

I would check if they're actually leaking first, since it's such a time consuming job (took me about 10 hours start to finish and it was the only thing I was in there for). Look for oil and feel the plugs to see if they're loose. They should be tightly sealed to the housing. The o-rings on mine were so shrunken, the plugs felt like they were going to fall out.
Here's a couple pictures from when I did them. Oil leak repairs-anyone relate to this picture?