92 Q45 fuel injector readings

[akgunny]

hey,
I'm new to the forum but have been lurking a few months.I have learned alot about the q45 here.I bought a 92 q45 180,00 miles for a little bit of nothing.It had poor acceleration when i bought it.I clean the maf sensor,throttle body,changed the oil,fuel filter,battery.The car has better acceleration now and seem to be doing ok but still has some problems.Its is idling at about 900 rpms when it cranks up but when i shift into drive the rpms drops to about 600.The lower the idle the more it shakes.I tested the injectors and knock sensors.my readings are below.Could all my injectors be bad?what about the ones reading over load?Thanks for the help and I'm sure I'll have much more questions.

injector by number
1 63.8 ohms
7 64.2
6 64.5
4 75.0

8 OL
3 71.5
5 88.4
2 OL

knock sensors
.680 ohms
.612

Thanks,
Stephen

[OwnerCS]

Welcome to NICO! Sorry for the delayed response.

Stephen -

There is a recent thread here with information about OHM meter settings below. OHM meters differ on readings. I had trouble getting mine set correctly the first time I check my injectors. From the above listing do I see injectors 8 and 2 showing open?

locating-fuel-injectors-problem-t520810.html

I had two injectors fail at approximately the same time. The following thread shows some of the steps taken to isolate the problem.

v8-became-a-v6-cyls-3-and-7-appear-dead-t503163.html

[maxnix]

Yeah, and if your plenum has not been off you are sitting on a disaster waiting to happen.

Be sure to read the under plenum hose threads in IOM and prepare for what must be done if you are keeping the car. Also, you need to really focus on the timing chain guide replacement.

[DeatschWerks]

Hey akgunny,

Are you sure those are the correct ohm readings? Those seem awfully high, like 5-6 times too high.

The Nissan injectors should be in the mid-high 13 ohm range.

[akgunny]

Thanks for the replies!I have a fluke 77-3 auto range multimeter with manual setting also.I went back today and retested the injectors at the wiring harness and directly at the injector on 1,2 and 4 on the manual setting. Here are my reading i guess it was on the wrong range.

1 13.4 at injector 12.8
7 12.3
6 12.8
4 31.6 at injector 27.3

8 OL
3 27.8
5 477 OL on maual setting Got 477 reading from auto range
2 OL at injector OL

knock sensor
1.480 .555

Is there anyway to tell if the timing chain guides have been replaced?I 'm going to try to get the service records from infiniti.

Thanks,
Stephen

[goody90q45]

#2 and #8 are easy to replace without removing the intake plenum. In the meantime, pour a full bottle of Redline S1 Fuel System Cleaner in a 1/2 tank of gas and see it it doesn't run better while you search for replacement injectors.

[maxnix]

And measure them both cold and hot. Use an high spec high 10 ohm resistor to calibrate your DVM.

[Q451990]

So 3, 4, and 5 are on their way out - and 2 and 8 are already gone. Sounds like time to buy a full set, and replace them and all of the hoses and gaskets under the plenum. Might as well replace knock sensors and their subharness while you're under there.

All of this is big $$$, so sadly it's time to make a fish-or-cut bait decision.

Heath

[akgunny]

hey,
I'm going to take a chance and order used fuel injectors.my question is when i search for 92 q45 fuel injectors i get orange,red,white ident.How do i tell what color i need?Are all 90 -93 oem fuel injectors the same?Thanks for the help.

[OwnerCS]

When faced with that problem last summer, I bought Phase II injectors for a 94 model. The time it takes to remove and replace the plenum is not small. Have you removed the plenum yet?

Once you have the plenum removed, you'll see hoses that need to be replaced no doubt. I bought some Phase II injectors and the DeatschWerks kit. Did you talk to DeatschWerks?

It just seems like so much work to replace used Phase I injectors with more used Phase I injectors.

Injector colors usually indicate a particular flow pattern - quality level. I bought all black labeled injectors last summer. Lots of people try to stay with a matched color set.

So many of us here have been down the injector replacement and the plenum hose road that we don't want to see anybody get burned with used parts that might have a short lifespan.