The short version is that I ohm tested an injector and got no reading at all. I get a 17.2 on the injector next to it consistently. My mental malfunction is that I didn't think you could get NO reading on an ohm test, just a low reading. But I have cleaned the terminals and keep getting no reading, so surely this is a sign of a bad injector, right?

The longer version is that the car has developed a miss over the last couple of days. I pulled the coil pack leads to find the offending cylinder(driver's side, middle). Swapped packs, no change. Pulled injector leads, got no reading on the injector. The kicker is that I forgot to disconnect the battery before I started pulling the injector lead off, and when using the screwdriver to help pry it off there was a spark between the injector lead and the screwdriver while it was still connected to the injector. So I'm wondering if "I" fried the injector or if it is my original problem. D'oh. My inclination is that my spark didn't fry it, but I'd like to hear what others think.

Thoughts?

 

You absolutely could get no reading. Touch one of the leads to your tongue, the other to the car... no reading. Why? Because your tongue doesn't complete the electrical circuit of the car.

How does it get no reading when testing the injector? Answer: The injector isn't allowing continuity. i.e. The injector coil is completely broken.

Sounds like you have at least two dead injectors. (17.2 ohms isn't acceptable either - that cylinder is running lean because the resistance is too high.) Time to replace all six with the newer pintle-less style + 300degree rails and new connectors. Problem solved for eternity. (If you keep putting the pintle injectors in, they're going to keep dying because of the ethanol in the gasoline - this was the cause of the bad injectors, not you.)

Bernie on TT.NET sells used injectors and rails for a great price, if you're up for sourcing a lower plenum or machining your plenum to accept the newer injectors. (There are 300Degree rails designed to not require a newer lower plenum or machining, though.)



P.S. You didn't fry anything by not disconnecting the battery. Truth be told, I don't even disconnect the battery when I pull the motor out, because I don't want to lose my stereo settings. You'd have to purposely short something out to have any problems at all... you can't really mistakenly cause an injector to short.

 

Thanks for the reply. I thought the 17.2 reading wasn't in spec either, but hadn't searched out the specs yet. The car needs to have the valve covers replaced anyway, so taking the plenum off was going to happen one way or the other. My plan was to send all six injectors to witchdoctor, but I will call them later today to see if there are things they cannot fix(such as an injector with no ohm reading!).

Thankfully the Z is a 3rd car, so while this is a bummer, there is no particular hurry to get it fixed.

 

Spec is 10-14ohms

Even if they're able to fix them, you WILL have the problem again shortly. I replaced all 6 injectors in 2003... had one go bad in 2004, one go bad in 2005, one go bad in 2006, one go bad in 2007, one go bad in 2008...

Had I spent a little extra on the retrofit in 2003, I'd have saved money within a year or two. These injectors simply cannot handle ethanol-blended fuels.

(By the way, the company is probably going to lie to you and say that they'll be fine after they fix them, but that's because they're either trying to get your business, or they're not familiar with Z32 injectors.)

Jim Wolf Technology article on injector failure

 

bernie is the way to go on this. he also sells newer injectors adapted into old style fuel rails for your using pleasure. direct bolt in plus a little upper plenum grinding and new connectors installed.

 

Ok, I may be up for this retrofitting project. I found a lower intake on ebay for $25 plus shipping out of a '94. It's out of a N/A car, but he says that it's the same as a turbo. Any feedback on that? Is he right?

 

One more thing to confirm...the newer style injectors you guys are mentioning are the 93-95 style, right?

 

Lower plenums are the same NA to TT.

Newer style came on different models starting 93 and 94 (I think NAs or verts got them in 93, TT in 94... or maybe the other way around... check twinturbo.net FAQ on differences between model years to verify), but they're easily identifiable by different connectors.

 

I asked about swapping the intakes from the old style to new style. Can I get away with swapping JUST the upper intake and be able to put the new style injectors / fuel line in or do both intakes have to be swapped out.

I swapped the 93+ onto a -93 motor and its fine, i didnt check for clearance or anything when it came to the injectors though.

 

That depends on the fuel rails.

If you have 300Degree type 4 rails designed to fit new injectors into the old style lower plenum, you're fine with the lower plenum you have.

If you do NOT have 300Degree rails and are instead using the new-style fuel rails, you need either the new style lower plenum, or you need to have your old-style lower plenum machined to accept the new style fuel injectors.

 

I hadn't heard about the ethanol blend problems. Glad I avoid gas stations that sell it anyway. It's getting harder and harder though. Everyone wants to sell a less efficient fuel for more money for some reason (sarcasm).