Injector color dot ID where do I look 91Q

[silverQ]

All I see is the plastic top do I have to remove an injector to see its color dots? Thanks

[3rd Q]

Silver,You don't have to pull the injector to see the dot, just the harness connector. BTW, just call Joe at Everything Infiniti and order the most recent iteration of the injector- they've been through 6 revisions for the '90-'93 Q that I'm aware of. In spite of that, they still haven't gotten it right. Just finished installing my 29th! injector between the 3 Qs! All brand new oem- have had the same one fail multiple times within months of each other. This latest one was installed 18 months/ 15k ago.

I absolutely love the Q, but the injector design on this car sucks. Have owned other Nissan products with no injector problems at all

Paul

Modified by 3rd Q at 12:16 PM 10/20/2005
Modified by 3rd Q at 12:19 PM 10/20/2005

[Raxephon]

Doesn't the dot color simply indicate which company the injector was made by for Nissan?

Or is it something else?

[Q45denver]

Doesn't the dot color simply indicate which company the injector was made by for Nissan?

Or is it something else?

No, I believe it shows the pattern and flow rate. I haven't been able to get my 1990 to run properly when the injectors are mismatched. 1994 and up is a pintle less design that doesn't have the same problems but to my knowledge can't be used on the Series I Q.

[96Qowner]

3rdQ ... any chance you've been running less than optimal gasoline in it? It's my understanding that injector troubles can usually be traced to poor detergent additives. All gasoline is NOT the same.

[3rd Q]

96 Q,

Have never run anything but BP(Amoco) Ultimate for the 10 years I've owned Qs- supposed to be the best available in my area.

Infiniti corporate insists it is a Mid-west gas related thing, when I ask why I never had even one fail in my Nissan minivan they don't have much to say.

Have talked directlly to Bosch techs, the oem supplier, who say they've done 6 re-designs without solving problem. The one I talked to blamed Infiniti for locating the injectors so deep in the "V" where it gets too hot.With these cars 10+ years old, no chance Infiniti will keep re-designing them- so if you love the early Q you live with it.

The dealerships say the Qs eat injectors like candy. Still love the Q, but the injectors suck.

Paul

[Q45denver]

[I agree, outside of rod bearings I have spent more for injectors than any other problem area on the early Q's. However, other than leaky valve covers neither of my 1995's have given me any problems. If the latter FI's could be adapted that would be the way to go. I may try a set just for kicks.

96 Q,

Have never run anything but BP(Amoco) Ultimate for the 10 years I've owned Qs- supposed to be the best available in my area.

Infiniti corporate insists it is a Mid-west gas related thing, when I ask why I never had even one fail in my Nissan minivan they don't have much to say.

Have talked directlly to Bosch techs, the oem supplier, who say they've done 6 re-designs without solving problem. The one I talked to blamed Infiniti for locating the injectors so deep in the "V" where it gets too hot.With these cars 10+ years old, no chance Infiniti will keep re-designing them- so if you love the early Q you live with it.

The dealerships say the Qs eat injectors like candy. Still love the Q, but the injectors suck.

Paul

96 Q,

Have never run anything but BP(Amoco) Ultimate for the 10 years I've owned Qs- supposed to be the best available in my area.

Infiniti corporate insists it is a Mid-west gas related thing, when I ask why I never had even one fail in my Nissan minivan they don't have much to say.

Have talked directlly to Bosch techs, the oem supplier, who say they've done 6 re-designs without solving problem. The one I talked to blamed Infiniti for locating the injectors so deep in the "V" where it gets too hot.With these cars 10+ years old, no chance Infiniti will keep re-designing them- so if you love the early Q you live with it.

The dealerships say the Qs eat injectors like candy. Still love the Q, but the injectors suck.Paul[/QUOTE

[Q45tech]

What does BP/Amoco have to do with what refinery formulation you purchase at a service station? What comes out of the pipeline and after the splash blend [as the tanker is being filled].

The BP/Amoco part is the 1 gallon of additive that is dumped into 5,000 gallons as the tank is topped off [road vibration mix as the tanker drives to the station].

Obviously if injectors don't fail [period] in ATLANTA [most of SE US], your gasoline formulation is at fault!!!!!!!!!!!!!!!!!!!!!!!!

[3rd Q]

Dennis,

Good to see you back- we've missed you on the board!

My point is that if other Nissan products I've owned have run the same gas with no failures and have also run same and other brands of gas in Chrysler, Audi and Acura vehicles I've owned in the same timeframe and never replaced an injector ( I've never had to replace an injector in any other car I've owned in my 25 years as a Midwest driver)- there is obviously a deficiency in the design of the early Q's injectors. If it's just an issue of gas formulation, wouldn't it have shown up on other fuel injected engines, especially the Nissan designed ones? Glad to hear they don't fail down your way - but they sure do around here!

BTW, it's not "my" gas formulation- I buy what numerous techs and the Infiniti dealerships say is the best formulation in my area.

BTW II, the '92 I bought as a parts car had 5 failed injectors in it- probably part of why it was sold. Researched it's history, spent 8 years in Florida, 2 years each in Arkansas and Minnesota, and less than a year in Chicago.

BTW III, what's with all the !!!!!!!!!!!!!!!!!!!!!! stuff? Obviously, I have a great deal of love for the Q (have owned 4 over over 10 years). For sure I don't have as much Q experience as you, but more than most. I'm just stating my personal experience with the injectors. No need to rag on me for that.

The good news is I've become an expert at plenum removal having done it 8 times now!

Paul

[Q451990]

The injector issues seem to be a regional problem... which would indicate a design "flaw" related to formulation - rare to see injector failures in Atlanta. Not sure why I had them with Q1. I think they were just clogged... long before I had internet support, so I don't think I ever ohmed them.

Atlanta is pretty hot in the summer so the Bosh engineer's theory on heat in the valley doesn't hold water in my book. Maybe it's a combination of heat and whatever chemical reaction takes place with reformulated gasoline?

I think it's something in the materials or design that doesn't agree with today's gasoline additives. Remember the Q was designed in the late 80s when gas was much better.

Heath

[Q45denver]

All I see is the plastic top do I have to remove an injector to see its color dots? Thanks

The injector dot is visible thru the cutout in the harness-no need to remove the harness.

Apparently the wiring inside the pre-1994 injectors breaks down over time due to the ethanol that has been added to gas. It may be as simple as adding some gas dryer to each tank of gas but I often forget to do so. What is amazing to me is how quickly this can happen even on brand new factory injectors. Aren't there some proposals to require 15% ethanol in gas nationally in the future.

[squeefoo]

I have to drive 12- 18 mi out of my way to put in non-RFG at over $3.00 a gal. just to avoid putting in another injector w/attendant plenum removal. Altough it seems to have more power with RFG (which I've only run 1 or 2x due to emergency), methinks due to running slightly leaner.

I have a '89 jeep Cherokee w/160,000 mi and it still has the original injectors. Which is a cheap POS, so WTF?

I don't think it's possible to buy non-RFG in the Chicago area. I am also really good at plenum removal.

I wonder if the '94 up fuel rails will fit 90 - 93 so the injectors can be used? Redo the harness so the connectors fit? Or are there electrical issues from the ECM?

[Q451990]

I believe the runners were redesigned, and there's a different spray pattern - so I'm not sure if it would work... Maybe someone else will know?

Heath

[silverQ]

k i got a set of 8 and swapped most of them as within a month like the 5-6 others started ohming bad and the car ran like poo .. all seems well now except for one that acts up at idle when the car is cold -- once warm can't tell is running and i can get sideways all day long in 1st WOT

fyi -- i am running one bank plain caps and one bank yellow dot caps no probs there L8r all

[maxnix]

Have never run anything but BP(Amoco) Ultimate for the 10 years I've owned Qs- supposed to be the best available in my area.

Don't think BP is a Tier 1 gasoline. Try Chevron. Probably too much ethanol from your federally subsidized corn growing farmers in your state.

Q45tech has had his original injectors for over 300K miles in SE US. Lots of BG44K and rail flushes.
Modified by maxnix at 5:49 AM 3/23/2006

[Q45tech]

For 5 months last Summer my Q ran almost continuously [10 hours per day] in ATL city traffic and idling AC on. That was with oem 1990 injectors with 280,000 going to 295,000 miles.

Can you say about the most severe under plenum heat test available.

Ohmed injectors yesterday still at 12.0 +- 0.5 ohms of course added my usual can of BG44k as the 90 day oil change is coming up.

Must remember to Quick Clean [BG] before the change.

[Q45denver]

States without ethanol are truly blessed. Q45tech if you get a chance could you explain again what ethanol does to injectors.

[3rd Q]

Don't think BP is a Tier 1 gasoline. Try Chevron. Probably too much ethanol from your federally subsidized corn growing farmers in your state.

Q45tech has had his original injectors for over 300K miles in SE US. Lots of BG44K and rail flushes.

Modified by maxnix at 5:49 AM 3/23/2006

Brian,No such thing as Chevron here. Have been told by numerous Infiniti techs that BP is the best tier 1 available in the area.

Paul

[3rd Q]

Silver,Welcome to life in the Midwest with the 1st gen Q injectors.

The folks from other areas can't relate. I'm tired of the disbelief that accompanies my statement that I've replaced 31 injectors.

With RFG gasoline coming to most parts of the country, they'll get a chance to see how dedicated they are to the Q when they start replacing injectors on a regular basis- and then replacing those injectors within months after they fail.

Then I'll get to ask them if they're running crap gas and ask if they are sure they're not doing something to make them fail prematurely !

Sorry to sound kind of PO'd, but pull the plenum 9 times and you'll understand.

Love the car. The injectors suck. Love the car. The injectors suck. Love the car. The injectors suck. Love the car. The injectors suck. Love the car...

Paul

[DrewQ45]

Maybe you need to do some research... find out which is the most damaging gas component affecting your injectors... Then some more research and find out which gas stations are using it, or better yet, the ones that may not be using it. Then buy strictly from them.

I am speaking from a point of ignorance here as I have no idea how gas is forumated state to state. Just throwing out an idea....

[maxnix]

Brian,No such thing as Chevron here. Have been told by numerous Infiniti techs that BP is the best tier 1 available in the area.

Paul

Bummer. No Shell, Exxon, or even Costco?

[Q45tech]

Ethanol picks up water and transports it to your fuel tank where it settles in the bottom of fuel cup and sock/fuel pumpump transports to injectors............rust corrosion.

Easy for the 10% ethanol to contain 30-50% [3%-5%] by gasoline volume water depending on tank/ground temperature.

Not so much a refinery problem but a tankfarm and service station problem.

Knowing that ethanol will be blended at tank farm the refiners are able to cheapen the grade significantly.........something thay cannot do to conventional gasoline to be used in the South.

A conventional premium must be ~~91 octane to work whereas a potential future premium to accept ethanol can be regular 86-87 which magically becomes 91 with 10% ethanol splask blended in at the tank farm.

Heaven help the places that get potential designed for ethanol yet never get it added in..........mix up cost savings along the pipelines or if the rail cars of ethanol don't come in that day to tank farm.

Heck we'll just cut the ethanol with tap water to make it until tomorrow

[Q45tech]

Anhydrous Ethanol is supposed to contain <1% water.

Field test for determining presence and amount of alcohol in gasolineEAA appreciates the permission of Conoco Inc. to base this field test procedure on one developed by the company.

ScopeThis method determines the amount, if any, of alcohol present in gasoline. This test is designed specifically for field testing where time and simplicity are important factors.

Summary of MethodA sample of gasoline is shaken at room temperature with an amount of added water. The volume increase of the water is proportional to the amount of alcohol initially in the fuel sample. Nine (9) parts of the gasoline sample are combined with one (1) part of water.

Appartus Required (for either of the methods below)Graduated Cylinder Method One (1) one-thousand milliliter (1000 ml) transparent plastic graduated cylinder (can be purchased at photo supply store).

Measuring Cup Method One (1) 2-quart clear plastic container such as a fruit juice container purchased from a supermarket. One (1) 4-fluid-ounce measuring cup (1/2 cup). One (1) 32-fluid-ounce measuring cup (1 quart).

PreparationClean Containers On the 2-quart juice jar, mark the level of exactly 4 fluid ounces (1/2 cup) permanently on the side (a piece of masking tape may be used).

ProcedureGraduated Cylinder Method. To 9 parts of gasoline sample (900 ml), add 100 ml of water for a total of 1000 ml in the graduate. Shake thoroughly, let stand for 10 minutes or until the gasoline is again bright and clear. Record the apparent level of the line between the gasoline and water. This "Final Volume" is used in the calculation below.

306-1 Revised 22 Apr 2005 FIELD INFORMATION NO. 306

FIELD TEST FOR DETERMINING PRESENCE AND AMOUNT OF ALCOHOL IN GASOLINEEXPERIMENTAL AIRCRAFT ASSOCIATION, INC. (EAA) appreciates the permission of Conoco, Inc. to base this field test procedure on one developed by the company.

SCOPEThis method determines the amount, if any, of alcohol present in gasoline. This test is designed specifically for field-testing where time and simplicity are important factors.

SUMMARY OF METHODA sample of gasoline is shaken at room temperature with an amount of added water. The volume increase of water is proportional to the amount of alcohol initially in the fuel sample. Nine (9) parts of the gasoline sample are combined with one (1) part water.

APPARATUS REQUIRED FOR EITHER OF THE METHODS BELOWGraduated Cylinder MethodOne (1) each one thousand milliliter (1000 ml) clear Pyrex or shatter-resistant glass graduated cylinder OR transparent chemical-resistant plastic (such as TPX) graduated cylinder. (These can be purchased from laboratory or chemical equipment suppliers.)

Measuring Cup MethodOne (1) each 2-quart clear pyrex, glass, or chemical resistant plastic container. One (1) each 4-fluid-ounce measuring up (1/2 cup). One (1) each 32-fluid-ounce measuring cup (1 quart).

PreparationClean Containers.On the 2-quart container, mark the level of exactly four (4) fluid ounces (1/2 cup) permanently on the side (a piece of masking tape can be used).

PROCEDURE

Graduated Cylinder MethodTo 9 parts of gasoline (900 ml), add 100 ml of water for a total of 1000 ml in the graduated cylinder. Shake thoroughly, let stand for 10 minutes or until gasoline is again bright and clear. Record the apparent level of the line between the gasoline and water. This "Final Volume" is used in the calculation below.

Measuring Cup MethodTo nine (9) parts of the gasoline sample (36 ounces or 1 quart plus ½ cup), add 4 fluid ounces (1/2 cup) of water for a total of 40 fluid ounces in the 2-quart container. Shake thoroughly, let stand for 10 minutes or until gasoline is again bright and clear. Record the apparent level of the line between the gasoline and water.

The Measuring Cup Method is intended to indicate the presence of alcohol and is not practical to evaluate the amount of alcohol. If the final line between gasoline and water is measurably higher than the ½ cup mark, the presence of alcohol is indicated.

NOTE: Erroneous results are probable if sample and water are not thoroughly shaken and mixed.

CALCULATIONGraduated Cylinder MethodNote the final volume and calculate the percentage of alcohol in the sample using the following calculation: Percentage of Alcohol in Gasoline = (Volume - 100 divided by 900) X 100.

Where: V = "Final Volume" of water as determined in procedure above (read at separation line between water and gasoline).

PRECISIONWithin +/- 1% alcohol if you measured and recorded accurately.

ACTION TO BE TAKENIn the opinion of EAA, and in the interest of most conservative operations, the following observations are offered:

If alcohol content is less than 1%, fuel will probably have no effect on aircraft.

If fuel contains up to 5% alcohol, caution must be exercised. Do not permit it to remain in tanks or fuel system for more than 24 hours, then drain and refill with alcohol-free fuel, ensuring that no alcohol concentration remains in fuel lines or sump. Vapor lock may be a problem. DO NOT FLY.

If alcohol content is more than 5%, DO NOT FLY. Drain the fuel system, flush all parts, replace with clean alcohol-free fuel and run up engine long enough to exchange fuel in carburetor bowl.

KNOWN PROBLEMSAlcohol attacks some seal materials and varnishes on cork floats of fuel level indicators. This could cause leakage of seals and release particles of varnish from floats, causing blocked screens in fuel lines or blocked carburetor jets. Excessive entrained water carried by alcohol could lead to fuel line blockage or blockage at screens or values when operating at low ambient temperatures at ground level or at high altitude. Fuel volatility is also increased with the addition of alcohol in a manner that is not detected by the Reid Vapor Pressure test, which is used to determine if a fuel meets the automotive specification. For example, a gasoline with alcohol will meet the Reid Vapor Pressure limit of 13.5 psi but it will behave as though it has a volatility of roughly 20 psi. Gasolines with alcohol will also phase separate. Phase separation occurs as the gasoline/alcohol blend cools, such as when a plane climbs to a higher altitude. When water that is absorbed in the fuel by alcohol comes out of solution, it takes most of the alcohol with it. The quantity that comes out of solution cannot be handled by the sediment bowl and tank sumps. Furthermore, if the alcohol is used to raise the octane of the base gasoline, the gasoline that remains will not have sufficient octane to prevent detonation. A good reference for this phase separation problem is: Paul Corp., Laboratory Investigations into the Effects of Adding Alcohol to Turbine Fuel, DOT/FAA/CT-TN88/25 July 1988, FAA Technical Center, Atlantic City International Airport, NJ 08405.

[Q45tech]

The problem is you can't get Anhydrous Ethanol cheaply so they substitute 5% water Ethanol.

Assuming the preblended gasoline is almost water free [say 0.25%] and 2.25 gallons of ethanol contains 14.4 ounces of water vs 2.88 ounces if 1% anhydrous was used.

Hopefully you see the problem in colder parts of US where the water separates.

[goody90q45]

Dennis- Maybe I missed it, but how does absorbed water in ethanol affect the resistance of the electrical function of an injector? I see how water, ethanol, varnish, etc. can plug an injector but don't understand how it would affect the electrical pulse needed to open and close the fuel feed. What does cause the resistance to degrade? Am I correct in saying that you can repair a plugged injector but the high resistance (internal wire coil) cannot be fixed.

[goody90q45]

Sorry to sound kind of PO'd, but pull the plenum 9 times and you'll understand.

Love the car. The injectors suck. Love the car. The injectors suck. Love the car. The injectors suck. Love the car. The injectors suck. Love the car...

Paul

Paul- Don't hold back! Tell us what you really think about the injectors.

[3rd Q]

Paul- Don't hold back! Tell us what you really think about the injectors.

Goody,

Yeh, I've probably vented enough on the injector issue. It's just that I'm noticing the perhaps early signs of injector number 32 failing (oem part installed about 19 months ago).

You'll notice that when this thread began a few months ago I was on injector 29!

I used to laugh about all the times I've pulled the plenum to replace injectors - however the ones I replaced in my unheated garage in December during a Chicago cold snap (daytime highs of 12-18 degrees) were just plain painful. Not to mention that it gets kind of expensive .

I really appreciate Dennis' info on the pitfalls of ethanol. I've heard the stuff takes more energy to produce than it actually yields- don't know if it's true or not. As a former farmboy, I give props to the ag lobby for getting that legislation passed. Farming is a tough business and many family farms would not exist without the subsidies. Doesn't mean that I like how the misguided policy screws up my engine though.

Anyways, if you live in an area with RFG you know what I mean about the injectors. Can't wait until the Feds mandate E85 gas everywhere, like they do in Brazil- then we are really screwed. Maybe if the cars are designed for it they'll work- I don't think ours will.

Paul

Modified by 3rd Q at 11:25 PM 3/23/2006
Modified by 3rd Q at 1:39 AM 3/24/2006