Injector Test

**Trav** · #1 (**permalink**) 03-18-2008, 03:18 PM

It seems like the rear bank of injectors on my 91 164L arn't working. They click just like the others but it makes no difference in the (poor) running when the signal wire is removed.

Can I verify proper operation of the injectors by removing them all from the intake, reconnecting the fuel rail, putting the ECU in injector test mode and providing fuel pressure by jumping the relay?

How can I check to see if they are clear or debris? I just replaced a dirty filter. I searched this BB and google with no DIY test found.

Thx

**ghnl** · #2 (**permalink**) 03-18-2008, 03:56 PM

I tested the injectors in our '84 Spider (Bosch L-jet) by pulling the injectors leaving them attached to the fuel rail, pressurizing the fuel system (cycle the key on-off-on) then cranking the engine (with the ignition disabled). Thus I was able to observe them squirting.

I also did this: remove the spark plugs, position the cam so that the intake valve was open then pressurized the fuel rail as above. Then I applied 12V to the connections at the injector while watching in the spark plug hole for fuel spray. (just a quick touch of the 12V, BTW) I don't know if that method would work with your 164. On our Spider I can peek in the spark plug hole and see the edge of the intake valve.

Now having described all that, I did find that the injectors were injecting OK. The poor running that I was trying to sort out was due to intake air leaks. And depending on what & where it was leaking intake air it would make different cylinders appear 'dead'. Have you thoroughly investigated your engine for that?

**Trav** · #3 (**permalink**) 03-19-2008, 07:37 AM

Is it OK to blow air throught the injectors? I shot some carb cleaner into the top and got some dirt out. I'm thinking about blowing (30 PSI??) in the bottom while giving the injector 12V. Would this blow trash out or mess the injector up?

Alfacliff · #4 (**permalink**) 03-19-2008, 07:45 AM

do not leave the power on the injector for very long, the coil inside will burn up.
cliff

**ghnl** · #5 (**permalink**) 03-19-2008, 02:00 PM

If you are certain the injectors are clogged (i.e. make sure it ain't an intake air leak causing your problem) then I'd suggest removing all of the injectors and having them properly cleaned. I used Cruzin Performance (and there are other that offer this service) when I resurrected our Spider. Quick turn around time (~ 1 week IIRC).

**kredden** · #6 (**permalink**) 03-20-2008, 04:24 AM

I agree. I used them as well. Rich will also check to make sure all your injectors are flowing at the same rate. One of mine was off by over 15% so I sent him another one that was good. The price is quite reasonable as well.

Kevin

**Trav** · #7 (**permalink**) 03-20-2008, 02:32 PM

They all squirt when I give them 12V from a battery and some fuel pressure.
I expected them to work when I put the injectors in test mode but they didn't and I am bit puzzled by it. They all make the same clicking noise, test or external 12v. Any thoughts?
Also, I'm assuming I can't just go to the local hardware store and buy O rings to replace the ones on the injectors, or can I? Local Autozone had a list for injector seals, but the part that showed up was wrong. Any good place to source these from?

Thanks!

**kredden** · #8 (**permalink**) 03-21-2008, 02:01 PM

You might try Auto Parts Fast at RockAuto, not sure if these are what you are looking for, if you go to the site there are some pics.

IRTEX Part # 1G1012 More Info
L-Jetronic

Part Image
$1.05 $0.00 $1.05
Add to Cart
BECK/ARNLEY Part # 1580021 More Info

Part Image
$2.81 $0.00 $2.81
Add to Cart

Kevin

**Richard2** · #9 (**permalink**) 03-23-2008, 09:33 PM

Not a bad price from Rock Auto on the re manufactured ones. I'm paying a local diesel guy $20 a piece to do mine. I avoid shipping to and from also.

**Trav** · #10 (**permalink**) 04-04-2008, 08:21 AM

The injectors just came back from Cruzin Performance. Most had iffy pattern and a couple were flowing significantly less than they should 30%! I will reinstall this weekend.

**kredden** · #11 (**permalink**) 04-04-2008, 08:55 AM

Good luck! Let us know how you make out.

Kevin

**Trav** · #12 (**permalink**) 04-10-2008, 03:08 PM

Got everything back together and it runs like a top.
So, injectors can clog up and make the car run poorly.
Cruzin Performance did a great job.

Thanks for all the help!

**kredden** · #13 (**permalink**) 04-11-2008, 04:30 AM

Excellent!

Kevin

**ghnl** · #14 (**permalink**) 04-11-2008, 06:36 AM

Glad to hear you got it sorted out.

danny164l · #15 (**permalink**) 04-13-2008, 10:14 AM

Yea I might have to do the same here car idles very low but idle jumps up and down 20 to 25 rpms its more of a feel and hear as if unregulated gas flow. Other than that car runs fine. Oh yea a good thing to do is to put an extra fuel filter in the engine bay itself right off the main fuel line that feeds the rails any kind will fit since you can use the little clamps and rubber fuel line hose and plenty of space. You can get one pretty much anywhere, I would get the clear type one so you can get a good Idea how clean the gas is coming because the gas we pump in our cars is VERY, VERY, dirty. I pinned pointed it because have have no air leaks whatsoever.