I'm trying to check fuel pressure on my '89 S2 and found out my gauge (which works fine on my 928) won't fit the S2 fuel rail, the gauge port sticks out of the side of the fuel rail instead of coming off the end so there's no clearance for the gauge between the fuel rail and intake manifold. Another "what were they thinking" moment.

I imagine there has to be someone else who's run into this and can suggest a supplier for a flexible hose or maybe a 90 degree elbow that will connect the standard male 12mm 1.5 thread port on the rail to a 12mm 1.5 thread female on the gauge?

I'lll be searching for plumbing parts while I wait for a reply...

 

Cheap solution is buy a spare fuel rail cap and drill/tap for an NPT fitting.

Be advised though, double check hood clearance to the fuel gauge before slamming your hood shut or youll end up with two dents in your hood like I have.

 

Sorry, request unclear.

I have the correct fitting for the rail, which's identical to the 928 test point fitting. The problem is I have an inline (strait) fitting on it since the gauge port on the 928 is at the end of the rail, not on the side of it. The gauge doesn't fit on the 944 S2 rail since the fitting is on the side of the rail and there isn't room between the rail and the intake manifold to fit the gauge.

I need either a flexible hose I can run between the rail and the gauge with a 12mm 1.5 thread female on one end and a 12mm 1.5 male on the other, or I need a 90 degree elbow with the same specs.

Drilling the cap won't help me.

Yes, I've encountered similar problems in the past. I fixed them with a rubber mallet and a wood block.

 

BTW, this is a "no start after clutch replacement" problem I'm trying to track down. I have spark at the plugs and a tach bounce so I think I can rule out the speed sensor and DME, but not the DME/Fuel Pump relay. I have a spare relay on order but all I could get on short notice was a URO and I've heard they can't be trusted. I have an OE part from eBay that should be here next week, until then I have no way of knowing for sure the fuel pump is working without a gauge.

 

Also, it could be the alarm system. I replaced a broken part on the driver's side door lock while I was doing general repairs, now the key doesn't unlock the door on the driver's side. I'm not looking forward to tearing that all apart again. It seems I can turn the alarm on and off using a key on the passenger side, but I suppose I can't be sure unless I disable the alarm. Looking into how to do that tonight.

 

I supposed I could find a hose with a 1/8 NPT female to 1/8 NPT male too. Those might be easier to come by...

 

I think I found what I need here:

 

Spray/Squirt a small amount (tablespoon) of gasoline into the intake or AFM and see if it starts. If it does you have a fuel delivery problem.

Arnnworx sells a great fuel pressure gauge that should work with the S2 fuel rail. Just order the correct size fitting.

http://www.arnnworx.com/catalog/inde...9#.WZ2ZjT596Uk

 

Thanks for the suggestion Paul, it looks like that gauge should work and it's pretty much what I envisioned, but down at the bottom of the description it says:

"Neither of our gauges can be attached to CIS engines or engines where an angled adapter is needed (examples: 944S2 & 968) for connection."

Not sure why it wouldn't work, it looks like it would.

I'll try some ether in the AFM to see if it will start, I ran out but have some on the way.

Regards,

 

Yes, you're right. Looks like the angle because of the intake runner is too tight. Crap.

It might fit, but it would be tight. You might ask Brace/Arnnworx if he has a solution.

You can use gasoline in place of ether, it works well at normal temperatures. Use a trigger spray bottle to squirt it in. Starting ether is too expensive!

 

I think I cobbled together something that will work from an eBay/Amazon combination:

- 1 12x1.5 female to 1/8" male aluminum adapter for the rail
- 1 1/8" female to 1/8" female 90 degree brass elbow
- 1 1.5" oil filed pressure gauge w/ 1/8" back male fitting

I also ordered the 12" hose mentioned above just in case I can't get clearance for the gauge hard mounted to the rail. I did find a gauge Lyndsey racing sells that's supposed to fit the S2, but they want about $85 for it so I figured if I could build one for $40 I'd be better off.

I'm really sorry I couldn't use the gauge I already have though. I'd hoped I'd be able to share a lot of tooling between the 928 and 944, but Porsche did something peculiar with the S2 and 968. Why am I surprised?

I don't know. $5/can delivered isn't that expensive. I really hate using gas in a spray bottle. I'm about an hour from the nearest hospital

What's the best way to open the intake? I looked at the AFM and couldn't really see an easy way to do it. The airbox is under the nose panel, so that isn't exactly easy either. Thinking I may pull the plugs spray in some fuel and put them back, which is a bit irritating since I just replaced the plugs the other day.

It's always something I suppose.

 

"What's the best way to open the intake?"
I unclamp and partially move the rubber duct between the AFM and the throttle body, squirt the gas in and push the rubber duct back into place. It's only for testing, not driving the car! You don't need much space. If I'm really lazy I move a little of the rubber duct and stick a small plastic hose pointed toward the TB and keep dumping gas into it.

 

Thanks. Pretty much exactly what I was thinking...

 

If you have an AutoZone nearby, they have a fuel pressure gauge kit to rent. Take a look at it. There is a myriad of connectors and tubing inside the kit. I don't know if it will be exactly what you are looking for, but it may help..just an aside.

 

Scott, a friend of mine just pushes a rubber hose with a hose clamp over the fuel rail nipple and rigs it to fit the fuel pressure gauge. Seems to work well.