Test Jigs and Equipment for the 944S, part two.

More test equipment and tools for the 944.

In part one, I discussed ways to make connections to the 944 engine for troubleshooting and diagnostics. This time I will go over some of the other tools and equipment I've found helpful when diagnosing issues and performing service on Gretchen.

I changed directions several times while writing this episode. It kept turning into a deep, drawn out descent down a rabbit hole. Several times while writing, I thought: "what's the point of this, it's way too basic and way too detailed at the same time", and I nearly killed it altogether. What's left here is the stripped-down version, where I only feature a couple of noteworthy tools, from the expensive to the cheap. If you're reading this and do want more details, or to ask questions, please post a comment. Also, now you can sign up to be notified about new posts by email - just fill in your email address and click subscribe. Unsubscribe any time.

9204 Oil filter socket - Hazet 2169

This is my one and only Hazet tool!  Naturally it works perfectly, and in my opinion, this style oil filter removal tool is the best way to go on the 944 engine.

If you aren't familiar with Hazet tools, they are first-class European tools that put Snap-On and Mac Tools to shame. Over the years, Hazet has often supplied OEM tools to Porsche, although I don't know if they are still doing this today. They are super pricey, and generally, in North America anyway, you won't see them very often. I'm not sure if they are commonly used in Europe; I have most often seen them being used by Formula One mechanics in old racing documentaries.

Mity-Vac hand vacuum pump

This Mity-Vac kit came with a bunch of rubber-like hose fittings, short vinyl hoses, and a brake bleeder kit.

I wouldn't be without one of these. A Mighty-Vac (stay clear of the cheap knock-off imitations) is indispensable for testing vacuum-operated parts like heater control valves, climate control air damper valves, and the fuel pressure regulator and damper. The pump is also great for checking the large vacuum hoses on the 944S engine for leaks. With a pack of various sized rubber stoppers, I'm able to check the complete set of AOS and idle hoses including the venturi pump, the brake booster, and the evap control hoses. My AOS hose has cracks all over the outer surface, and one day I'll get around to replacing it, but it still holds vacuum for several hours. Because I was able to test it with the Mity-vac, I could see that it was holding vacuum just fine and I didn't need to replace it right away. I was able to put the money I would have spent on this hose ($60.00) to better use on other parts that really did need to be replaced immediately.

Vacuum gauge

The lowly automotive vacuum gauge is great diagnostic tool, but has largely fallen by the wayside in favor of more glamorous tools like the OBDII Scan Tool. But the vacuum gauge can detect and diagnose a ton of issues, including ignition timing, ring condition, excessive blowby, and sticking lifters. it's even possible to check exhaust back pressure by hooking it up to your exhaust emissions test port. There's all kinds of info on the internet explaining how to interpret vacuum gauge readings, so I won't rehash all that here, but if this sounds intriguing to you, look it up. A vacuum gauge can also be used to test vacuum operated controls like the evap purge valves, climate control air door actuators and heater control valve. Pick one up, and learn how to use it. They're really cheap too.

12V incandescent test light

Because sometimes you just need to know if there's power and ground. Way quicker than any other test method. The incandescent ones are your best bet in my opinion, although the LED type has its uses too, like when you want to be careful not to pull more than an amp or two through the circuit under test. Why not one of each?

Open barrel crimpers

This IWIS open barrel crimper blew me away with the quality of crimps it produces. It's not perfect, but damn near. And for less than $20.00!

The automotive industry as a whole uses open barrel crimped wire connections for everything. They do this not because it is cheap, in fact the tooling used by all manufacturers for crimp termination is outrageously expensive. They use this style of termination because it is the best way to terminate a wire in the automotive environment. It's a gas-tight connection that can take temperature extremes and vibration day in and day out for a very long time without failing. Why would you want to use any other kind of termination? Do you really expect your wire connection to give you years of reliable service in the hostile automotive environment? If the answer is yes, then you don't want to be using insulated (red/blue/yellow) crimp connectors, you don't want to be soldering connectors onto the wires (this makes a brittle connection that will crack), and you certainly don't want to be twisting and taping over bare wires or using wire nuts, etc. You don't want to be crushing the connector onto the wire with pliers or sidecutters, either. You want to use an open barrel crimper like the one pictured above, and you only want to use high quality (read: not from Amazon.com, eBay, or Alibaba) open barrel crimp connectors from a real connector company like TE Connectivity (AMP). The quality of the connection made by the pairing of this IWIS tool and TE Connectivity AMP connector terminals is simply amazing, given the cost. I've used many low-cost open barrel crimpers, and this one is by far the best I've ever come across. TE Connectivity AMP connectors are readily available from Digi-Key.

While not perfect, the quality of this crimp connection rivals that of hugely expensive automatic production crimp machines. Just compare it to any factory crimp you can find on your 944, which was made with some very expensive production crimp tooling, indeed. Why would you want to make connections on your Porsche any other way?

 Digital Thermometer

This digital thermometer has two channels, a difference function, Min/Max, and 2% accuracy for about $75.00. It comes with the two thermocouples shown here, and there are several other styles of thermocouples and probes available, including a long dip-stick-like probe that could be used for oil temperature measurements.

For a tool that isn't all that expensive, this little 2-channel thermometer answered a lot of questions for me last fall when I swapped in a "good used" radiator and had all kinds of cooling issues that had never happened before with the old rad over two or three cooling system drain and refills. I think that particular adventure will be the subject of an upcoming post, but for now, here's the condensed version: I now know that Gretchen's temperature gauge is very accurate (despite what almost anyone will tell you), that an IR temperature gun is pretty useless, that the thermostat is working perfectly, and that the cooling fans are coming on right at the correct temperature. With all that info, I knew with 100% certainty that I had a nasty air pocket in there somewhere and it didn't go away until I pressure bled the cooling system while the engine was running with the heat on, twice. So yes, it was a good used radiator!

It's also really interesting to watch the cooling system working to maintain a temperature differential across the engine by monitoring the water pump inlet and block outlet temperatures, and to measure various points in the air intake tract, and fuel rail temperature, exhaust header temps, HVAC inlet/outlet temps, you get the idea.

Fuel injector cleaning/flow bench machine

A fuel injector cleaner / flow bench kind of pushes the envelope of DIY, but owning my own machine makes a lot of sense for me. For example, consider the replacement cost of a set of injectors if they should get lost in shipping. It's almost $400.00 per injector, if you want real ones from Porsche, and if they will even still supply them in the coming years. Consider that sometimes, you get a set back from cleaning and they don't ever work again. That's happened to Brent Burnett several times, and even happened twice in a single Edredas video episode. Consider that unless you always have a spare set of working, clean injectors on hand, your car is down while they're out for service, even if the turn around time is only a week. That's too long to go without driving Gretchen! So I decided to buy this machine along with some peace of mind. Now I know what kind of cleaning and flow test fluid is being used, I know exactly how they'll be handled, and I know my injectors won't get lost in the mail. We have 3 cars, and I can clean the injectors on them any time I want or need to. Win-Win, as far as I'm concerned. And what a difference clean injectors make, holy cow! The only negative thing about this unit is that it doesn't have enough current drive to handle low impedance injectors like those used in the 944S during the cleaning cycle, and you have to do only one or two injectors at a time. Easily fixed though, with a fairly basic mod that will change the operation from batch fire to sequential during the cleaning cycle. That could maybe be another blog post...

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