Are all of my injectors bad?

[95Gstman]

Need some help guys. I recently bought a q that was running rough so that I could put it in my 240. The guy said that he had stripped the intake manifold and that was why it was running like it has a huge vacuum leak. Well, I started tarring into it today and come to find out the manifold is fine. The car will run but I have to keep on the gas to get it to idle and it has no power. I can floor it and the car will go about 5mph. I decided that while I had the manifold on I would check the injectors. So I was under the impression that the correct spec was between 10-14 ohms. Well none of them are within that spec. All of them were over 20. And there were 2 that read nothing at all. Could all of them be bad? Need a little insight because I have never messed with a vh45 before. Thanks for any help. O, and by the way the car is a 1994 q45. Thanks.

[95Gstman]

Also, forgot to mention that when I took the iacv off the plenum there was pretty much no gasket at all.

[Q451990]

Sounds like you have a whole bunch of problems. Injectors with a reading other than open will typically perform pretty well if they're not physically clogged with something. Those reading open are dead.

Heath

[Q45tech]

When injectors are attacked by ethanol and water in E10, they swell and the crimp between the copper coil winding and the external connector pulls apart, At first it just shows up as ever increasing resistance.

This resistance is temperature sensitive so it may read ok 12.8 ohms cold and become bad when the engine heats the injector body up to 174F after 10-15 minutes.

Necessay to read resitance BOTH cold and at operating temperature!

All Q45 injector are identical in resistance beut all every inexpensive [under $1000] VOM is different due to internal battery voltage and calibration.

Not unusal for inexpensive VOM to be 5-10% accurate thus the wide 10-14 ohms published in FSM. Not that injectors vary just that test equipment and operator experience varies.

I've measured hundreds of brand new injectors and they all read 12.8 ohms +- 0.15 ohms {12.65>12.95} at room temperature

[goody90q45]

So I was under the impression that the correct spec was between 10-14 ohms. Well none of them are within that spec. All of them were over 20. And there were 2 that read nothing at all. Could all of them be bad?........

Has the car been sitting for a while non-op? I bought a 90Q a while back (not the one in my sig) that had been sitting for a year with 2 dead injectors, one that was disconnected, and 3 others that were plugged. Even with all that I could still get up to 45 mph. You could also have a fuel pump issue. Is the check engine light (CEL) on?

Don't fret too much over the 6 FI reading 20 ohms resistance if they're all in family (real close). You'll get a different reading on the 6 next time they're checked. The other 2 injectors may even come to life for a few minutes. Go to Radio Shack and get a 10 OHM resistor to check your voltmeter. With one probe on each lead, the resistor should read 10.0-10.5 OHMS resistance. Were your readings with the engine hot or cold?

If you can replace the 2 dead injectors and get her driveable, a bottle of Redline S1 fuel system cleaner in a 1/2 tank of gas (or 2 bottles in a full tank) will do wonders. Dsagers in the parts forum is a good source for used injectors (and fuel pumps).

The IACV gasket needs to be replaced. You can cut one yourself if the stealership isn't close.

We're curious about the CEL and any codes.

[95Gstman]

The car has not been registered or inspected since 2006. I tested the injectors cold. I did not pay attention to if the check engine light was on before I took the plenum off. I used my multimeter instead of my friends today, and got some better results. Here is what they were

0 00 22.711.6 011 11

So, do you think that I could just be running on 3 cylinders and that is my problem? Where is the best place to get new injectors. I have seen them go for anywhere form $45 - $130 and all sorts of brands. Thanks for the help guys.

[goody90q45]

It's not as bad as you think. You're running on 4 injectors, not 3, but the one that's ohming at 22 won't be alive much longer.

Since you have the plenum removed can we assume your readings are taken directly on the injector pins and not at the harness plug? If so that would rule out any bad harness wiring.

OEM new injectors are about $170/ea through our sponsor, IOS. You can get aftermarket for about $100/ea and there's been a guy on Craigslist (he may be a NICO member also) who's been trying to sell a set of 6 new for $75/ea. There's used injectors in our parts forum for $25-$35 each but they can be a crapshoot. If you don't have a problem removing the plenum again if they fail early and your pockets aren't deep enough to afford new FI, then the used injectors will work well.

[95Gstman]

Yeah I am testing them directly on the injector. I don't know if you guys have used rockauto, but I have bought from them in the past and have not had a problem but here is a link to there injector selection. What do you guys think?

http://www.rockauto.com/catalog/raframecatalog.php

I could not get it to direct link but you can look at it through their catalog if you have time.

[maxnix]

read Heath's post on BGW (I think) injectors.

Only use US manufactured ones.

[95Gstman]

read Heath's post on BGW (I think) injectors.

Only use US manufactured ones.

Sorry, I am new to the q45 and this forum. Who is Heath and what is BGW? I also noticed that you are located just down the road from me. Maybe we can meet up sometime. Anyway, thanks for the help.

[Q451990]

Here's my thread on the BWD injectors.

zerothread?id=347484

Heath

[95Gstman]

Very informative post. Just makes me sad that now I must spend 800 dollars on injectors. Are the BWD's still holding up for you Heath?

[Q451990]

They're doing fine! That said, I haven't put that many miles on the Q since I installed them... maybe 6K, so I'm not a great indication.

Heath

[95Gstman]

One more quick question. I do not know if any of you guys looked at the link I posted, but how does the price of injectors range from $50 - $180? I know quality is a factor but could it really vary that much?

[Q45tech]

Remanufactured means cleaned and polished up used units from junk yards or factory rejects, manufacturers over stock.

My last junk yard half rail [4 sed injectors] lasted 6 months whereas the 4 brand new oem units have made it 18 months so far.

Many times you get what you pay for.

Everything depends upon the labor cost to replace them whether one takes the chance on doing the same job 2-3 times.

[silkysmoothyjud]

Just replace the injectors under the plenum with top dollar OEM so you do not have to remove the plenum again for a while. Fudge the ones that can be replaced w/o plenum removal 1-2-8-7 (leave one screw in the cover of number 7) if you are trying to save a buck....

[95Gstman]

Quick question. I have searched around but can not find a definitive answer. Are the sr20 injectors the same as the phase 2 q45 injectors? Can the be interchanged? I see that some places say they are not the same while others say they are. Thanks for the help guys.

[qship96]

Why guess.....just order the correct part number listed for your car.

Why do so many try to find and purchase parts for a different model of car than they own?????

[95Gstman]

Because I found a used set of sr injectors for a very good price. I know most of you guys do not suggest used injectors but I do not have the money to buy all brand new ones and I do not mind changing them out again later on down the road.

[Q451990]

Might check with Deatshwerks - they would know.

Heath

[95Gstman]

Good call. I will ask them and post in here what they say.

[silkysmoothyjud]

Later? Down the road? If you get the wrong injectors for that motor you will do it again the next day. Then you will try and save a buck again, only to pull that plenum again, again and again...trust me dude.....been there....

[95Gstman]

http://www.q45.org/vhpower/info.shtml

That link says that the sr20 injectors are identical to the vh45 ones. I was just trying to make sure that they were. If they are identical, why would you not want to know. I think you are kind of making it a bigger deal than it is. If the injectors are not the same and do not work then I will just have to save up and get new vh45 ones but if they do work, then I will have fixed my problem for an affordable price and I will be able to let everyone on this board know that they have another option.

[qship96]

http://www.q45.org/vhpower/info.shtml

That link says that the sr20 injectors are identical to the vh45 ones. I was just trying to make sure that they were. If they are identical, why would you not want to know. I think you are kind of making it a bigger deal than it is. If the injectors are not the same and do not work then I will just have to save up and get new vh45 ones but if they do work, then I will have fixed my problem for an affordable price and I will be able to let everyone on this board know that they have another option.

Re-read your quoted article VERY carefully...........big difference between sr20 and sr20DET, including the fuel injectors

[95Gstman]

Most of the time when I say sr20 I mean sr20det. Anyway, I know that the vh45 takes 370cc injectors as does the sr20det.

[silkysmoothyjud]

If you get a slight but noticable PITA vibration after your motor is warm after installing "rebuilt" or used injectors, you will know what I am talking about. No CEL either. I never would have found that misfire had I not put that injector in myself. It was #4 too....

[95Gstman]

Just to let you guys know. I put the sr20det injectors in and my q runs just fine. I also contacted DW and they verified that the injectors are the exact same. Just letting you guys know.

[oldmako]

Please re-post at the end of this thread every six months or so. It would be nice to know how you made out with them as they age and get some miles on them.

If an interchangeable part fits, works to spec, lasts and it can be had for less, then why not use it? I guess I'm just obtuse. I like having cash in my hand instead of somewhere else.

[silkysmoothyjud]

I wonder how much the new ones would cost? The same as the Infiniti? I am gonna call. If those used injectors last 2 months, I will eat one of mine! lol jk good luck....