Injector resistance - do I have a problem?

[bruce.weiland]

Hi guys,

Borrowed an ozone generator from a patient who has a local brick and mortar auto detailing shop. He tells me that it does a great job on getting rid of smoke odor. It has been running for 24 hours, I will let it go 12 more.

While the interior is being treated I decided to clean the MAF and the throttle body per the instructions on Q45.org.

The air filter looked very good, but was Korean made, not Nissan. The bottom of the air box quit a bit of sand and leaves that I vacuumed out.

The MAF looked great, but I gave it the full treatment anyway.

The throttle body of my “94” active looks different that the illustration on Q45.com. The 45 degree bend in the rubber hose, is actually part of the throttle body (made of metal) and has a second butterfly that is open. It was very clean until I opened the second butterfly. All kinds of dark carbon came out of there.

Then I check the resistance on the knock sensors and injectors from the harness.

Please tell me what you think.

Knocks 575k ohms and 555k ohms. Both OK right?

Injectors (website gives normal range of 10 to 14 ohms)

1-13.8, 7-15.0, 6-14.0, 4-13.8

8-13.8, 3-13.4, 5-14.5, 2-19.2

Do I have a problem or potential problem developing with #7, #5 and #2 injectors?

Thanks

Bruce

[Q45tech]

You are describing a Q throttle body with Traction Control Option.Number 2 injector is the only one showing signs of attack by alcohols so far.

[bruce.weiland]

Dennis,

Thank you for the response.

Any rush to change #2?

Bruce

[maxnix]

I would replace it with new and put the other 3 suspect ones where they can be pulled without pulling the plenum.

[bruce.weiland]

Sounds like a good idea. At 132k and no service records yet, I am sure that the "under the plenum" work needs to be done.

In general I will drive under 300 miles per month on this Q, mostly 1.5 to 5 miles trips with 2 or 3 250 mile round trips per year.

I think I will put off the afore mentioned repairs for a few months.

[elwesso]

you might see if the resistance changes when the car is warmish....

[bruce.weiland]

OK.

It was stone cold when I check the resistances.

[Q451990]

The good news is that you can replace #2 without pulling the plenum...

Heath

[bruce.weiland]

Heath,

Thanks. Mike sold me a nice injector. I will talk to him tonight about replacing #2.

However, if you have any input on how to replace it, I would appreciate any advice.

Bruce

[3Q Jay]

Bruce, there are a lot of threads on injector replacement.most important: yank the 15A fuse for fuel pump when engine at warm idle just before the job to evacuate residual fuel (run until stall). then crank her over a few times, she may even start and run briefly.make sure your #2 phillips is well engaged prior to turning. tap with a mallet, and 'crack' the screws loose.2 small slot screwdrivers to 'pop' the old one out. make sure you retrieve all o-rings (1 big, 1 small) and the pintle cap.

[bruce.weiland]

Jay,

Thanks. Mike and I had a phone conversation about the r and r, but we missed going over the fuse. Thanks that helps a lot.

I will do some thread searches.

Bruceanother LA Q owner

[maxnix]

Do the above with the gas cap released!

[bruce.weiland]

OK

[ScottJackson]

those two phillips screws are always tough to remove. I don't even bother with breaking them free by use of screwdriver anymore. I use a small pair of locking pliers (vice grips) to grab the outside top of the screw and turn it just a bit (counter clockwise as normal) to break it free. Then I use the phillips screw driver. I then spray some penetrating lube (WD40) on the top of the injector where it goes into the fuel rail. I then grab the top plastic carefully with pliers and twist it right and left while pulling upward to get the injector out. When putting the new one in I wipe a tiny bit of petroleum jelly on the o-rings and then place a wooden hammer handle on top of the injector (not on the little brass pin, but just to the side on the flat plastic part) and lightly tap it down in snug. Then put the little cover back on with the two phillips screws and put the wire clip back on.

[bruce.weiland]

Scott,

Thank you. I may get the injector from Mike tomorrow or Friday. It will be in by Sunday.

Bruce

[ponzy]

i am on the process of my plenum job, just so you know, i had my fuel rails/ all 8 injectors serviced by DEATSCHWERKS, my # 2 injector is out of spec (15.9 ohms) and after the "basic service" (from DW service) its ohmed at within normal spec now ( 12 ohms +/-0.5 ohms ).

I think most of the values you've given is almost getting out of spec. ( --- as per FSM ---is 10-14 ohms but as per Q45tech is 12 ohms +/-0.5 ohms------) so ,just think about it.......to get to the rails and all injecotrs you gonna have to deal with removing the plenum! And plenum job as for me (newbie DIY-er) is pretty difficult yet challenging. and besides you get to know your 'baby' so i guess it's worth it....

[bruce.weiland]

When I do the plenum I will get the rest of the injectors rebuilt.

The injector I bought from Mike was serviced by Deatxhwerks.

[bruce.weiland]

Thanks everyone, Mike, Brian, Jay, Scott, Wes, Heath. I did the job today. Just as easy as everyone indicated.

EXCEPT for operator error.

The most difficult part was getting the old injector out, and that wasn't too bad.

I reversed all the steps and cranked her over, and cranked her over, and cranked her over.

It would not start. I checked to see that I had the fuse well seated. I did.

Cranked some more with no result. I did notice that when I turned the ignition on I did not hear the pump.

I pulled the fuse, looked at it, it seemed fine and reinstalled it upside down.

More cranking with out any results. Still acted as if no fuel.

I thought, maybe the fuse was defective and I just couldn't see it. I decided to install a different fuse. This time I noticed that I had install the FUEL PUMP fuse in the empty spot between the air blower and the air bag. I moved it up three slots to the FUEL PUMP fuse spot and this time when I turned the key, I heard the pump.

Cranked her over a couple of times and she roared back to life.

Maybe it is just my memory, but it seems that this car accelerates "stronger" than my '91' with 1st gear start or my '95' ever did.

Again, thanks to everyone.

Bruce