My Q won't start

[30bino09]

The temperature got to below freezing overnight and my 1994 Q45 slept outside. When I turned the ignition this morning it started then shut off again. Tried again several times but it's not turning over. The starter's trying but it's not turning over. What could be happening?

Louis

[oldmako]

Is your batt strong enough crank the engine at a near normal rpm while starting? Or is it barely turning over?

[Haitian_King]

The same thing sort of happened in my MDX about two weeks ago. The darndest thing. It was about freezing and I was walking to the car after work. I go to start it, and the damn thing just wouldn't turn over. Tried it twice with no luck. On the third try, I kicked the gas pedal. Not flooring it, but a sharp jab with the toe. The engine started and it acted as if nothing happened. Not a hint of trouble since.

[Q45tech]

Oil low temp viscosity corrected for miles of use should be appropriate for the starting temperature.

Oil increases viscosity every mile of use as lighter components boil off [Noack Index] and into pcv system. A new10w can easily become a 15- 20W after 1500-2500 miles especially in cold weather!

I always use 0W40 even in ATL mild winters since we ocassionally see 10-15F-20F a few weeks per year......................selecting your Dec- Feb oil correctly is much cheaper than replacing a battery or starter earlier than necessary.

This Sunday will go down to 15F and Mom needs a ride to early Church need I say more.

Reminds me my 3 year limit on installed battery will be up in May 2008.

PLAN AHEAD so you never see problems!

[qship96]

Yet another reason to only use a FULL synthetic oil....lower Noack numbers{evaporation of oil} result in a much cleaner intake system{pcv,plenum,throttle body,etc} , while providing faster circulation and easier cranking in cold, and better protection in extreme heat,while resisting viscosity breakdown and oxidation{thickening} better than non-synthetic oil.......What a shame most people dont know all the advantages of synthetics, they only think synthetics are beneficial for extended oil change intervals

[30bino09]

Initially i thought so, but I tried a "jump" from my wife's van like when you have a dead battery but that did not help either. I am trying to understand the oil issue the other guys are talking about. My car is due for an oil change, so could the oil not be the correct crank temperature in the cold because of viscosity? If it's too thick it may not turn over. Is that what they are saying. My other theory is cold spark plugs. What do you think?

[Q45tech]

Do yourself a favor ! Splurge buy 6 quarts of Mobil 1 Syn 0w40 for less than $35 and have it put in with a new filter.

http://www.mobiloil.com/USA-En....aspx

[GseaQ]

The 2 most probable things are a dead battery (how old s yours?) and less common, but still possible, a hydrolock from a leaking fuel injector. How was the engine running previously - silky smooth so you don't really feel it when it idles? Did start right up with 1 or 2 revolutions of the starter or did it wind over a few times before catching? If it's a dead battery, a boost will get it going so you can immediately get a new one installed. If it won't crank with a boost, STOP trying and leave it overnight. That'll allow the raw gas in the bad injector's cylinder to drain past the rings so you can start it tomorrow. Then you'll need an oil change right away and get the bad injector replaced.

Like I said, these would be the most likely causes in my mind. Others may have other ideas. I have to say, we've been through many cold winter periods with our Q and it never failed to start due to thick oil. Of course, dirty, old thick oil may be the last straw for an already weak battery.

Good luck,Glenn

[GseaQ]

I see you tried boosting it, so don't do anything else now. Wait until tomorrow. If you try too hard to turn over a hydrolocked engine you could damage something internal.

[30bino09]

it started right up then cut off a very few seconds later. Couple weeks it's been idling a bit shaky but there is nor hesitation when I excellerate etc. I will see if it starts up tomorrow.

Thanks for all the input so far.

[GseaQ]

When you get it running you should probably go to a Nissan or Infiniti dealer to have a power balance test done with the "Consult" scanner. The cylinder with the least RPM drop (if there is one) may very well have a weak/leaking injector. They should charge you 1/2 hour labour for the test (at least that what they charge here).

Have you had the Throttle Body Service done annually to keep the throttle body, MAF sensor & plenum clean? If that stuff is dirty you'll get a rough idle. What about fuel system/injector flushes - every year?

Cheers,Glenn
Modified by GseaQ at 5:19 PM 1/17/2008

[sdkhalsa]

I would recommend pulling the fuel pump fuse and then taking the engine through a few cranking cycles to make sure that you do not have a flooding problems. I noticed on my 94Q that if the engine does not fire right away in cold weather it can build up alot of excess fuel. You may also have a certain amount of injector leaking which is causing a particular problem during the cold start cycle. One other item, is your ECU temp. sensor in the proper range? It could be malfunctioning in the cold mode.

[maxnix]

it started right up then cut off a very few seconds later. Couple weeks it's been idling a bit shaky but there is nor hesitation when I excellerate etc.

When did you last change your fuel filter? BG44K? Might measure your fuel pressure.

[Mint Q45A]

I vote for the 'flooding' issue. I had exactly the same symptons. In order to try to find the problem injector I removed the plugs and unpluged the injector harness, then run the leakdown test, just to confirm that the fuel was leaking into one or more cylinders. After 15 to 20 minutes I cranked the engine for a couple of revolutions (still with no plugs) - fuel came flying out the plug hole from cylinder #2!! Inspecting the lower O ring on the injector I clearly saw how deformed when compared to a new one

Note: the injector ohmed at 11 Ohms. It was just the O ring

The issue here is that you can have more injectors with O rings in similar conditions and may fail too.... You may want to replace them all
Modified by Mint Q45A at 9:23 AM 1/19/2008

[sdkhalsa]

I had a bad flooding problem due to a bad injector o-ring, it even hydrolocked the engine briefly.Now I replace the o-rings every time an injector comes out, being very meticulous in lubricating them and inserting them. It only takes a nick or a pinch to force you to remove the plenum again. Also noted that examining the plugs did not reveal the bad cylinder. The ignition is so hot that there was no residue. Had all of the injectors tested to make sure there was no leak coming from them. I like Mint's approach for testing.

[30bino09]

Thanks I appreciate your imput.The fuel pump fuse is in the car under the steering by the parking break pedal ..correct? Does the 94 Q have a timing belt or timing chain. Also if there is flodding when/how will the excess fuel be gone. Iam smelling fuel now and also even when it was drining I recently would smell fuel when using my hot air.

[30bino09]

can anyone step by step me on how to release the fuel pressure to replace the fuel filter? Does it involve starting the car?

[30bino09]

Hey Maxnix, how do I release my fuel pressure. I want to replace my fuel filter. How long would it take for the flooded fuel to evaporate off even if I unplug the fuel pump fuse and run some cycles.

[Mint Q45A]

Unfortunately the best way to release the pressure does involve removing the fuse for the fuel pump and cranking the engine, but if your suspect yours is flooding, I don't recommend you do this.....unless you first remove all the spark plugs, allowing any liguid fuel to exit the cylinder(s) without building any pressure and causing any damage.

If you have not removed the plugs yet, I believe you could do the following in order to replace the fuel filter:

Remove the gas cap - this releases any possible back pressure caused by the fuel gases/evaporation in the tank.Let the car sit for at least 24 hours - since most likely you have a fuel leak (into one or more cylinders), the pressure inside the fuel rails/hoses/filter will eventually drop to zero. At this point you should be able to disconnect the hoses, but be prepared with a rag and a small container (small empty water bottle works perfect) so that you can catch any remanent fuel that may come rushing from the hoses - I would first do the return line, then do the one that goes from the filter to the fuel rail - this two hoses sit side by side on the passenger side of the plenum, under the mechanism that holds the trottle cables - the one further back (closer to the firewall is the return line).

NOTE: a fire extinguisher readily available is not a bad idea when working with fuel lines...

Any fuel that may have leaked into the cylinders will go down past the piston rings and end up contaminating the engine oil - reason why you need to change the oil once you finish the repairs and before you start the engine again.

One thing I strongly recommend is that you always remove the fuse that feeds the fuel pump, even if you are not planning on cranking the car to remove any fuel pressure. I was doing something similar on my car and I thought I had removed the fuse... the next day I saw the driver's side window down and decided to close it - opened the ignition and hit the switch.... but the fuel pump came on, the hoses were disconnected and I made a big (and dangerous) puddle of fuel inside the garage....

Hope this helps...

[30bino09]

thanks mint. This is what i did today before I read your reply. I removed the fuel pump fuse and cranked the car and it almost started. I then alternated the cranking with the fuse in then fuse out. Everytime I cranked it with fuse out it felt like it would start. It did start a couple of times briefly but did not maintain the idle. I continued several times cranking the car with the fuse in and fuse out. It eventually started about the eight time with the fuse in, smoked for a short while but kept the idle for a long time. I drove it round the block a couple of times then parked it in the garage. Should I let it sit until I change the Oil? I already purchased the fuel filter as well, just need to get it in. It's still a little rough on the idle. Where should my idle rpms be. It's now bordering around 600. Should I be very concerned about Injectors. Would a rough idle come from bad injector or fuel filter. This note is already long but I have to mention. That morning I encountered the problem I had pressed the accelerator to the floor then turned the ignition. That's actually a summer procedure the owner manual recommends, I didn't remember i shouldn't do it in the winter.

Thanks again

[sdkhalsa]

To run your car temporarily, I would depressurize the fuel system when you are done running it . Rev the engine and then pull the pump fuse. Try starting it a few times with fuse out so as to further reduce the fuel in system. This procedure should reduce the flooding problem when you go to restart. You need to locate which cylinder is bad and deal with it-- the situation will not get better.

[franknitty69]

i also recommend a deep cycle battery (optima). it has higher cca's and last a helluva lot longer than 3 years. optima also has 2 yr warranty (maybe 3) on specific batteries.

i have run the red top for starting and have used the yellow for audio in the past.

[Mint Q45A]

Sdkhalsa's tip is right on....this basically burns most of the fuel and reduces the pressure in the fuel rail, prior to shutting the engine off. But I believe there will still be some fuel left, which may end inside your cylinder(s)....

30bino09: by restarting the car serveral times apparently you were able to clear and burn whatever fuel that was sitting in the cylinder(s). I don't recommend you do this anymore - assuming you do have a flooding issue. You may hydroloc and damage your engine... The rough idling could be caused by a wet plug not firing (which is the result of the leaking injector), but it could also be from a dead injector (not necessarily leaking)

You can first test the resistance on the injectors (just in case you have a dead injector) but I recommend you do all the necessary tests to confirm if in fact you have an injector that is leaking. If this is the case, the problem will not get better withouth you identifying the fauly injector and replacing the O-rings. NOTE: You can have more than one injector leaking....

[30bino09]

Thanks Mint and SDKHALSABut wouldn't i get hesitation during acceleration if I had a dead injector? I do think I have a faulty injector if I am flooding. On a DIY scale of 1-10. How difficult is it to replace an injector or O-ring.

[maxnix]

I do think I have a faulty injector if I am flooding. On a DIY scale of 1-10. How difficult is it to replace an injector or O-ring.

You tell us which one and we'll tell you if the plenum has to be removed.

If it has never been off, better plan on the under plenum hose and KS replacement scheme.

[Mint Q45A]

Replacing the O Rings on an injector is not that hard and they cost just a few dollars.

What makes it really hard is getting to the injector (assuming it is not #1, #2 or #8 - these can be accessed without removing the plenum). Once you have clear access to the injector, it is a matter of removing the two screws that hold the cap on top of it - be careful not to loose the small rubber piece under the cap and the little "washer". Then you have to try to pull the injector off the fuel rail -you may need to add some light oil around the top and let it sit so that the O-ring inside loosens up a bit, then try to pull on the injector. Be carefull not to hit the tip (seal) of the injector; this plastic part is usually very brittle and will break easily.

If your injectors are the ones that came original with the car (or at least have the similar milage/age) and you already had one O-Ring fail on you, there's the possibility of other O-rings also failing in the future. You may be better off replacing them all (saving yourself the trouble of removing the plenum again and, more importantly, eliminating the risk of severely hydrolocking and damaging your engine). You may want to consider having the injectors fully serviced by Deatwerks -You can send the fuel rails withouth going through the trouble of removing (and possible damaging) the injectors. This service is not cheap, but once done, you will have peace of mind - no more leaks...

Caveat - Injector O-rings are not supposed to fail, but several members, including myself, have seen it happen.

My two cents...

[geauxapl]

Dumb question - do you suggest getting the replacement O-rings at a dealer, or do you have another recommendation? Thanks.

[Q45tech]

O-rings were designed for gasoline ONLY not ethanolized gasoline which cause them to swell and possibily leak.

Using a ethanolized fuel tends to cause other problems in fuel pumps and hoses........................use E10 at your own risk and expect problems.

[goody90q45]

Dumb question - do you suggest getting the replacement O-rings at a dealer, or do you have another recommendation? Thanks.

I'm not sure, but you'd have a tough time getting the exact o-rings made from the correct material from anywhere but the stealership. I think you can get a set 8 of each o-ring for about $25-$30 so cost is really not an issue.

On the other hand.....I haven't read about anyone taking the time to research the material of construction (buna, calres (sp)?), measure them, and pick compatible Parker o-rings.

Tech- Is there an o-ring material that stands up to the E10 fuel yet still has the same qualities as the OEM orings. Can you supply me with a Parker #? I've got a storeroom full gathering dust.

[Q45tech]

Since Georgia doesn't use E10 [yet coming soon by Spring] we haven't bothered to mix our own for testing.

If you look at 2002 returnless systems the hose has a viton/teflon [flurohydrocarbon inner liner].

http://www.efunda.com/designst...hanol

There are just under 165,000 gasoline stations in US chose carefully!

http://www.gulfcoastseal.com/downloads/ord5700.pdf