2002 q45 intermittent not starting?

[q45inca]

Hi,

my q45 with about 90k miles has been very reliable for several years, recently sometimes it fails to start. Turning the ignition key either produces no result (engine not even trying to turn) or produces a click. After trying several times with exactly the same results it finally starts just fine.

But most of the time it starts immediately. Battery is 3 years old and strong (checked voltage etc).

What are the most common problems which could cause it? Some starter solenoid or relay? Where would it be located and how to replace it?

thanks for your help

[djwarner]

If your battery is three years old, it's still your prime suspect regardless of the voltage when its not under load. Go to an auto parts store and have them check the cold cranking amps.

After verifying the battery, the starter and/or solenoid are next.

[q45inca]

Thanks, I've just had the battery tested in a shop and it's a good one. Looks like a solenoid to try next, here is a text from an old thread I've found on this topic: "Took the solenoid off the starter instead, betting on the problem being there. It was! A plastic guide in the solenoid had disintegerated, causing it to intermittantly not engage. Looked like heat caused the plastic to break down. Replaced solenoid, problem solved.". Seem the started is located close to the exhaust and the heat was causing this problem.

[Q45man1]

In some cases, the circuit board for the crank position sensor or cam position sensor may have an improper solder joint due to solder deformation caused by heat stress caused by the existence of flux residue during the soldering process. This could cause no start condition, intermittently will not crank.

The crank position sensors, camshaft position sensors need to be replaced. I believed there was a recall on these and mine were both replaced 6 years ago.

[q45inca]

Thanks Q45man1, checking my service records the cam sensor was done at 45k miles and crank position at 50k miles so luckily it should not be a problem. For now I've ordered the solenoid on the web (about $90 inclusive) and will see how it goes. BTW - nice colors of your Qs, also my favorite (my 02 is the same)

[q45inca]

update: I've replaced the starter relay ($20 and 2 minute job to change it, so it's an easy step) but it has not fixed the problem. I've got the starter solenoid and lifted the car to change it, but bad news - the solenoid is attached by 2 Philips screws which look like they will not come out without removing the starter.

Upper bolt removal of the starter is a nightmare from what I can see (and from what the other nico threads mentioned).

Is there a way to replace the solenoid without removing the starter or is it time to take the car to a shop?

thanks

[q45inca]

Copying from the other thread - I have had the dealer replace the solenoid today.

They quoted 1h, and after looking at it changed the quote to 3h (I ended up paying for 2h). They had to remove the starter and lift the engine from the mounts to change the solenoid. The 2 solenoid to starter mounting screws are 1inch long and are hard to turn (looks like locked in with some Locktite style liquid fastener) - in case it helps someone who may be still trying to undo them and pull out the solenoid without removing the starter. Just make sure to be ready to swear a lot :-)

Let's keep the fingers crossed that's it. I will post back if more work is needed.

[Skibane]

In some cases, the circuit board for the crank position sensor or cam position sensor may have an improper solder joint due to solder deformation caused by heat stress caused by the existence of flux residue during the soldering process. This could cause no start condition, intermittently will not crank.

That's just plain weird. The CPS doesn't do anything at all until the engine actually starts spinning - so why would it prevent the starter from even spinning the engine?

[elwesso]

Yeah not following that either.. It could create a no start condition, but a no-crank condition...

BTW a Q45 cam angle sensor doesnt really have any circuitry in it.. its basically just a wheel with a bunch of little slits in it.

[tanomack]

I will post back if more work is needed.

So I take it no more work had to be done and the starter solenoid was the problem.

[q45inca]

Correct, after the starter solenoid got replaced, never a problem in almost two years so far. Thanks.

[Infinismo45]

Hey Q45inca, I am new to this board, I have just joined so I am unable to PM you. I have recently bought a 2002 Q45 with 53k original miles. The car in superb condition but I am experiencing the same issue as you have mentioned [intermittently not starting]. I would like to take a shot at replacing the Solenoid, do you think it is even worth giving a shot myself or getting it replaced by a good indy mechanic or a dealer as you have chosen to do? I have already replaced the Starter relay, that didn't help, and I have switched out the battery and cleaned up the terminals, that didn't help either. So looking at these boards and a few people complaining about the same issue and everyone seems to have replaced the solenoid and that has fixed the problem. My other question is, if you can guide me as to where the location of the starter is once i have the car lifted up, taken the undercarriage cover off - where should I be looking to find it? Do I need some ridiculous tool? Ratchet extensions etc? Thanks for your help.

[q45inca]

hi Infinismo45 - in short: don't do it yourself unless you have a lot of time and all the tools you can think of plus more. I consider myself fairly skilled DYI-er and my tool set is comparable to an average auto garage (including a hydraulic hoist to lift the whole car up) and I'm very glad that I gave it to the dealer. Dealer spent triple the time they first estimated, having skilled and trained mechanics and access to all the factory tools and manuals. BTW, I have not had any problems for the last 2 years since the solenoid replacement. It's a great car - congratulations on your purchase! Actually it's the best car I have ever owned and I've owned tens of cars including top of the line brands from Germany and Italy (plus other European, American and Japanese cars). This one is a keeper :-)

[sam111sam]

I'm writting this post for the benefit of any one who owns an Infiniti Q45 2002-2006

Well, I had the same problem TWICE
The car would not start from the first time, it only clicks as if the battery is flat. It has nothing to do with the battery or the cables.. It is a TYPICAL problem in the Infiniti starter. The dealer knew it right away.

The problem started when the car was only 30k miles but was very rare It became more persistent at 60k Miles, so I replaced the starter motor with a used one from ebay ($60)

Now at 100k miles, I have the same problem again. The dealer does not sell the seloniod as a separate part, only the whole starter motor assembly at $400. So I will either buy again another used one from ebay ($60-80), or may be Denso for $180 from Amazon.

I love this car, it has been very nice car

Three other typical problems of Infiniti Q45 2002-2006

1) The engine can stop suddenly with no warnings , but it would start again after sometime and runs well for a week or two. Then it happens again. This is your Cam and Crank shaft sensors failing to send the signal to the car control unit. There is a safty recall on this DO IT

2) The Airbag light would come on indicating a no communication with the car control unit. Relacing the air bag will not help. replacing the seat belt per-tensioner will not help. The dealer replaced lots of parts in 2004/5 and the light comes on again. At the end they found the loose connection inside the seat that would momentarily discount while driving on a bumpy road. A fault reset will work for few week, till it happens again. The permanent solution is find that loose connector and solder it. It did work for me and no fault for 5 yrs , now I'm back to the same problem. I will just reset it when it comes on (find the airbag reset procedure on Youtube )

I read in one of the forums that the Airbag light problem has something to do with the failing starter motor, but I can not find any logical link to support this view

3) This is more serious problem. The car would lose engine oil at a high rate. Again this is a common problem in 2002-2004 models. Infiniti would open the engine and replace the rings. Very big and expensive job. I have done it at 35k miles. Now at 100k miles it is coming back but to much less extent. I lose one quart every 3000 miles while normally I would only lose 1/2 quart. If you do the engine compression test it would show good result (90%).

The above problems are common, you can read about them in the forums

If you suffer from any of these symptoms, do not break your head

Thanks God for these forums where kind people like you guys share experience's this has saved me 1000's of $$ and so many hours over the year

Finally, if you think Infiniti is not reliable, TRY a BMW 7 Series. Then you will appreciate Japanese quality. Over the past 20 yrs, I have owned so many cars in my household including 4 BMW's (5, 6, 7) , 3 Chevrolet, 3 Honda's (CRV, Perlude, Accord, Legend) , 1 Toyota (landCruiser) and 1 Lexus LX470, 3 Infiniti's . I can tell you that the Honda and the Lexus were the best, followed very closely by Infinity which offer very good value for money.

At the end I just appeal to anyone who would benefit from the information above to PLEASE SHARE your experience and the ultimate solution of the problem at the end.. You will spend less than one hour doing this, but so many people will benefit.

[elwesso]

Welcome to NICO!! Thanks for sharing those experiences.. The oil consumption issue in (3) is pretty well known, and overall not really an issue if you just keep an eye on the oil level.

[Dachristianman]

I'm having the same starter issue. I get the click, but if I turn the key a few times, it will start. Looks like I'll be in for pulling the starter to replace the solinoid. I never saw a good answer in this thread as to which was the best solinoid purchase option outside of an entire starter from the dealer. I would hate to drop $400 on the entire starter.

Tom