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View Full Version : Poor cold starting, glow plugs?


the_bluester
05-07-2011, 10:41 AM
Hi all, not a D40 related issue, rather an R51 Pathfinder, but given the shared mechanicals and the mechanical nous around here I thought I would post up here as well as on the Pathfinders forum.

The R51 is becoming noticeably less enthusiastic about cold starts, just not as crisp as it used to be and if the garage door is left open at night it is obviously worse. It is not a cranking problem as it still turns over just fine (New battery a couple of months ago) it does not seem to be at all down on power and it blows no noticeable smoke on acceleration. My first thought was glow plugs.

Has anyone on here had to do glow plugs yet? The Pathy has just hit 180,000 km and is an 05 model.

tweak'e
05-07-2011, 10:47 AM
possibly dropped one or more glows. test them first.

but also check battery voltage. battery can get a bit low making it a bit harder to start. easy enough to put battery on the charger and see what its like the next morning.

the_bluester
05-07-2011, 10:51 AM
Is there any decent functional test of the glows? I know I can check for 12V on them when it is keyed on but that is about my extent of knowledge. Or can I check for an element resistance too to check for an open circuit one?

Battery condition I am pretty happy with, it turns over as quickly as it ever has, in fact last winter when the original battery started to fail it would turn over a lot slower cold but it still started fine. Now it is cranking well but not starting well.


Guess I will finally need to replace my multimeter, I turned it on a year or two ago and it let the smoke out and I have never got around to replacing it.

tweak'e
05-07-2011, 10:54 AM
multimeter is best way but otherwise use a light bulb. just need to take power rail off the glows first.
i would still be inclined to charge battery up. i've had before on other vehicles, turns over perfectly fine but just a bit hard to start when it gets cold. charge battery up and it starts perfectly.

Dave
05-07-2011, 10:55 AM
What are the glow plugs worth ?

Id just change them.

the_bluester
05-07-2011, 11:13 AM
I am a bit worried to find that out. Given what they are they should be about $10 each, but I am sure that is a figure needing a multiplier put on it.

Old.Tony
05-07-2011, 11:20 AM
I would check the glows as well. If the thing runs smoothly once it's going, it's probably not going to be fuel waxing up, blocking the filter or anything else like that.

Dave
05-07-2011, 11:24 AM
4 Glow Plugs Nissan Pathfinder R51 YD25 YD25DDTi 2.5L | eBay (http://www.ebay.com.au/itm/4-Glow-Plugs-Nissan-Pathfinder-R51-YD25-YD25DDTi-2-5L-/130521826446?pt=AU_Car_Parts_Accessories&hash=item1e63b5048e)

Cheap, But if it was me, Id get plugs made in Japan.

the_bluester
05-07-2011, 11:25 AM
That was my first thought, but my Xtrail (Diesel) is currently parked outside and starts flawlessly even when it is covered with ice (It has been a couple of times already this year)

I might go out now and at least give it a test with the test light to make sure it is not something silly like a failed glow plug relay and no glow voltage at all. My mother is driving the car to Gippsland in the morning and then overnighting there before coming back, so I really don't want tomorrow or the following morning to be when it refuses to start.

Edit, I was replying to Tony. But I have found those glows too. I have a trade price supplier for genuine stuff so I will see how shocking the price is there first. Sometimes Nissan spare parts prices are a nice surprise, but not often.

the_bluester
05-07-2011, 12:33 PM
Well, it has battery voltage or near it on the glows for 20 seconds or so on key on (Tested by a test light) I guess I will need to finally buy a new multimeter to go any further than that.

Dion
05-07-2011, 12:38 PM
Check continuity through the plug, with the rail off.

Pix
05-07-2011, 12:46 PM
I have this problem on my D22, just had major major serivce done and mechanic reckons only thing left would be glow plugs.

the_bluester
05-07-2011, 12:51 PM
Yep, next step. Better get out and buy a new meter tomorrow.

Bugger it, I wanted to save up and buy a Fluke scopemeter, but I just can't justify one! Will have to be a more normal DMM.

Scubamurph
05-07-2011, 01:52 PM
Just take each plug out and check it visually.
If there is corrosion/burning/wear on the tip replace it.

There - now you don't have to buy a new multi-meter :big_smile:

I didn't have a multi-meter and had to do this after 100k - 120k miles
on my old 1.9 TD Citroen.
Not sure how east they are to get at in the D40 though.

Murph

the_bluester
05-07-2011, 09:48 PM
They look like they should be pretty easy to change over, the worst I should have to do is remove a bit of inlet plumbing and the shroud over the top of the engine.

the_bluester
06-07-2011, 05:54 AM
Bought a new meter today (Fluke 179 with a clamp volt/ammeter) which should arrive tomorrow. Stand by to stand by until I have the meter and the car in the same place.

At least I can clamp over the glow plug feed to check it is passing about 60A for the four of them and then work my way down the links on the engine to see if I drop 15A or so each time I drop a glow plug from the test.

the_bluester
06-07-2011, 08:48 AM
Course with a bit of thought, I can't do DC current with the clamp (But can do DC voltage, work that one out!)

But either way, I need the thing to be able to do any further testing and the clamp meter is a handy item to have. I may simply need to disconnect the glow plug DC rail to measure them individually for element resistance.

tweak'e
06-07-2011, 10:24 AM
i'm surprised you didn't just test them with the test light. ie use the glow plug as a ground, if test light lights then its ok.

don't go pulling them out, you can actually break them when removing. also visual inspection doesn't show much.

the_bluester
06-07-2011, 10:39 AM
I did not have time to check them last night with the light before the car went out. It means pulling a few bits and pieces off to have them in a state where they can be tested individually.

On the plus side, I really did need a new meter in any case, this has just made me get off my arse and buy one finally. It is probably two years since the old one died (It was about 15 years old at the time)

the_bluester
08-07-2011, 09:41 AM
Well, might actually be battery, 12.5V floating voltage after 24 hours sitting following a 300KM drive and it fell to around 9.8V on cranking. Straight up to 14.3V once started so it looks like it is charging OK. Have to do some current leak testing first but you would reckon something that would pull it down in condition fast enough to drop to under 10V 24 hours after a decent length drive would kill it dead after a few days and a few days unstarted seems to make no difference at all to it.

Old.Tony
08-07-2011, 10:41 AM
The Navara draws about 500A to crank its engine over so a big voltage drop isn't actually a huge surprise. Seeing 12.5V on it after sitting for 24 hours is a little disturbing, but it's not entirely the end of the world.

It would be interesting to charge it and do a load test on it. Takes hours to do - lead acid batteries don't respond quickly unless you directly connect +ve terminal to -ve terminal with a Stilson wrench. If the battery is faulty, the load test will reveal it.

If you can pop the top off the battery, check the specific gravity in each cell. one could be markedly different to the rest - that'd be the problem child, if any.

the_bluester
08-07-2011, 10:47 AM
Yay, more test gear to buy!

It does have removable tops on the cells, better get myself an SG tester tomorrow. I would have thought dropping to under 10V on a single cold start would be risking getting low enough for the ECU to drop the ball if it had to be cranked for a while.

Will still do some glow plug testing I think. Now I have a new meter I can resistance test them. Have to do them individually as paralelled up they should be about 0.2ohms which would be pushing it for any sort of meaningful reading, unless it came out at .4 ohms or something, indicating two dead plugs.

Old.Tony
08-07-2011, 10:49 AM
Shame you aren't nearby, I'd just lend you mine. Could also drop my battery into yours and see if that makes a difference, etc etc.

the_bluester
08-07-2011, 11:00 AM
I have a jump start pack to boost it with, I was going to open the garage tonight so it gets nice and cool tonight and then start it with the pack in the circuit to see if that gets it to start properly in the morning.