This injector tester work?

[VMAX1]

Looks to easy to use on a Porsche. Anybody ever tried one?



Here is a link where they sell them. PP used to stock them when I did a search.

http://www.aeswave.com/EFI-Quick-Probe-Orange-Probe-p8823.html

[scarceller]

I'm sure the device works but I can spot a dead injector with a long shank screwdriver placing the tip of the driver against the injector body then place my ear on the top of the screwdriver's handle. You can hear the injector snapping open and closed. Try it it really works well. Listen to the injector this way then unplug the harness to the injector and listen again.

[petercory]

Send them to Marren Fuel Injection in CT, you'll get back your original rebuilt and flow tested and matched injectors for about $175.

[VMAX1]

I sent mine to WitchHunter awhile back, had one stick when I fired it up. Tapped with a hammer and started firing. So, if I hear a clicking on the injector that means it firing? I prob still have a vacuum leak somewhere, can't find any, did have a lot of leaks. I need to build a vacuum smoke tester.

[scarceller]

Quick test for injectors:

- disconnect O2 sensor
- Get engine warm and at idle
- while at idle unplug the IdleControlValve, so that the DME will no longer correct idle speed.
- Unplug each injector, one at a time. As you unplug the injector you will notice a idle drop. Pay attention to the behavior of idle and exhaust sound as you unplug each injector. As each injector is unplugged you should notice same behavior on idle speed.

If you get to an injector that has no effect on idle you have a dead cyl here. But be aware that it could be fuel or spark.

This type of test is known as 'Cyl Balance Test'.

Also note that a injector that's dead will result in bad fuel economy as well. This is because of the O2 sensor feedback loop. If a cyl fails to fire it simply acts as an air pump and dumps tons of O2 into the exhaust stream. If the dead cyl happens to be on the LHS bank (cyl1-3) where the O2 sensor is located then it sees all the extra O2 and assumes a false lean mixture. This is feed back to the DME and the DME richens the remaining 5 cylinders! It can richen them as much as 15% and your MPG will be toast.

[VMAX1]

Well explained scarceller! I have read about that test and didn't quite get it. Thanks for simplifying. I will try that tonight. I'm guessing an injector can be intermitent?

[r-mm]

Very useful thread! Can someone give a simple procedure for pulling the injectors?

[VMAX1]

On the left side, remove heater plumbing that goes to the blower. Remove fuel line, have rags ready for gas. On right side, remove air filter, then air box. 4 bolts inside and 2 nuts on rubber mounts on outside of air box. One nut in back of air box. Disconnect fuel lines. When you remove fuel rail, 2 bolts, remove with injectors. Remove locking clip to get injectors off fuel rail. That's it, and a few hours. Oh yeah, I would go back with new injector seals.