[GaryDrohan]

Hi Folks,

Long time reader, first time poster.

I've recently noticed my 2011 1.6 CRDI taking longer to start under the following conditions:

- The car has remained off for 10+ hours (basically in the morning).
- The colder the temperature the longer the crank before it starts.
- Immediately after the engine starts, I can switch it off and it will start again very quickly (No warm up time!).
- No fault codes are showing from the ECU
- No warning lights show AFTER startup although the battery light does stay on during the crank.
- The crank does not slow down while I'm turning the key.
- Cycling the glow plugs doesn't help.
- The engine runs no problem once started.

I've posted a of the engine during a startup at 4 degrees Celsius.

I'm really stumped for ideas as to what this is, however, here are my guesses so far:

- Bad fuel pump
- Bad check valve in fuel pump
- Throttle position sensor isn't giving a reading through the OBDII, this may have something to do with the start up procedure
- Weak battery
- Faulty glow plugs

Literally everything else is running perfectly with the car - No other issues once started.

I'd appreciate any feedback on this folks, it has my brain rattled.

Cheers,
Gary

[Dazzler]

  Gary,

I would very much suspect it is the glow plugs. This is the most obvious and easiest thing to remedy provided they have not become "welded" into place as can be the case after many years. They cost around A$100 on ebay (over here anyway)

GENUINE HYUNDAI I30 HATCHBACK 1.6L CRDI DIESEL ALL MODEL GLOW PLUG 1 SET (4EA) | eBay

If you are the type to do it yourself they will need a good squirt of WD40 or CRC well before you try to remove them or preferably use a reliable mechanic which shouldn't cost that much.

Is she generating much smoke at start up?

 

[GaryDrohan]

Hi Dazzler,

This was probably going to be my first port of call as it seems to get worse with temperature...

However, there's ZERO smoke from the exhaust under any conditions, it's something I've never seen in the rear view. I also reverse out of my drive and would occasionally get the smell of exhaust but no fumes/smoke.

Also, once started, I could switch the engine off immediately and it would start with 2-3 cranks, rather than up to 10 seconds of it.

I'll have a look at sourcing some glows either way, not a bad thing to have.

Cheers mate

[xiziz]

Smoke might get trapped in the DPF though, not sure how much get through there.

One thing that caught my eye was that you wait for a few(7-8) seconds after the coil preheater light goes out before starting to crank(the one that looks like a cinnamon bun on the lower right left side of the rev indicator lights).
I find mine starts best if I start crankin the moment it goes out, the colder its out, the faster the coils will cool down, and those seconds might just be enough to lower the temps too much for a clean start.

Its free to test before replacing any glowplugs.

[The Gonz]

I always crank the moment the light goes out. I imagine it reflects the glow plugs going out once they reach operating temperature. Waiting any longer is the same as not waiting enough.

[diesel1984]

Hi Dazzler,

This was probably going to be my first port of call as it seems to get worse with temperature...

However, there's ZERO smoke from the exhaust under any conditions, it's something I've never seen in the rear view. I also reverse out of my drive and would occasionally get the smell of exhaust but no fumes/smoke.

Also, once started, I could switch the engine off immediately and it would start with 2-3 cranks, rather than up to 10 seconds of it.

I'll have a look at sourcing some glows either way, not a bad thing to have.

Cheers mate

Glow plugs on modern diesel engines with 1600bar injector spray pattern in 8 stages does not play big role in cold starting. If all 4 plugs are shot this can ofcourse make starting a bit longer then before but hwlere we are talking about 2 sec longer time.
Right.

Did you recently changed fuel filter?

[GaryDrohan]

I changed the fuel filter back at 60k miles (@ 92k now) and never saw the issue in question until recently (about 80k).

Also I've been using the same fuel since then.

I can't remember if it was a Hyundai filter but didnt see any problems. Also no problems when driving.

[Asterix]

The glow plugs will continue to heat up to 90 seconds after the light goes out, so waiting a few seconds to crank will just extend the preheat.. 

It does sound like it's running rough a few seconds when started, which is always a good indicator for a few dead glow plugs (mine did that when 2 plugs were dead)

[nzenigma]

The glow plugs will continue to heat up to 90 seconds after the light goes out, so waiting a few seconds to crank will just extend the preheat.. 

As above    and above again as Gonz said.

You may notice white smoke when the motor fires. Again an indication of shot glow plugs.  The last set I got for Au$50 from Poland.
If you are going to change them yourself , easy job, use our search engine for procedure.
 Especially remember to REMOVE THEM FROM HOT ENGINE.

[GaryDrohan]

Thanks for the advice guys,

I'll get the plugs checked with the multi-meter over the weekend and see what state they're in.

In the event I need replacements, can anyone suggest a solid brand to use? I was thinking Bosch or NGK?

[Dazzler]

Can't really go past the genuine ones I reckon. They seem readily available. 

Obviously Bosch and NGK should both be ok too, given their long history and solid reputations. 

[diesel1984]

Quality is the same but bosch plugs are 3x cheaper then NGK. Oem plugs are NGK metal plugs. Ie you can also buy ceramic ones.

[Dazzler]

Quality is the same but bosch plugs are 3x cheaper then NGK. Oem plugs are NGK metal plugs. Ie you can also buy ceramic ones.

I'm guessing ceramic would be better, but dearer?

[diesel1984]

Sure they are better.

https://www.rexbo.eu/ngk/glow-plug-95232?c=100152&at=18432

[Dazzler]

Sure they are better.

NGK Glow Plug 95232 | Glow Plug Parts | rexbo Car Parts

Cheers for that. 

are ceramic glow plugs better? - Google Search

[nzenigma]

WE may be ignoring the drop test. Where's Lester 

[xiziz]

The glow plugs will continue to heat up to 90 seconds after the light goes out, so waiting a few seconds to crank will just extend the preheat.. 

It does sound like it's running rough a few seconds when started, which is always a good indicator for a few dead glow plugs (mine did that when 2 plugs were dead)

Cheers! Thanks I had no idea, guess I don't have to turn the ignition off and on again before cranking after taking my odo readings when filling up.

[GaryDrohan]

***UPDATE***

Some tests were carried out on the glow plug rail and the circuitry also:

1. Both the fuse and relay are working.
2. 12V is getting to the glows through the lead plug.
3. Resistance across the glow plug RAIL is 2800Ω which seems way to high for functioning glows.
4. The was NO current draw on the battery when the glows should have been active before cranking the engine (engine was stone cold).
5. The connection to the glow plug rail was disconnected and the engine started as normal.
6. A current draw test was done on a TDI engine at home and 30A was being drawn when glows were active.

I think, based on these tests, that ALL the glows on my car are probably shot.

Any final thoughts before I fork out?

[diesel1984]

Remove rail and all for nuts and take readings. There is no way that you can find fault on plugs with any other method.

[Dazzler]

I think, based on these tests, that ALL the glows on my car are probably shot.

Any final thoughts before I fork out?

We told you so... Thanks for the update. 

[nzenigma]

Remove rail and all for nuts and take readings. There is no way that you can find fault on plugs with any other method.

In this case no need. If one of the four was good, reading would be 1 to 5 Ohms.

[diesel1984]

Remove rail and all for nuts and take readings. There is no way that you can find fault on plugs with any other method.

In this case no need. If one of the four was good, reading would be 1 to 5 Ohms.

This plug rail is in parallel connection. So only right test is to take measures with rail removed

[nzenigma]

Remove rail and all for nuts and take readings. There is no way that you can find fault on plugs with any other method.

In this case no need. If one of the four was good, reading would be 1 to 5 Ohms.

This plug rail is in parallel connection. So only right test is to take measures with rail removed

 not wanting to labour this , yes the 4 glow plugs are connected in parallel.
Therefore, if each good plug measures, say, 4 ohms, the measurement from rail to ground (engine block) will be 1 ohm.
You will also have a low reading with just one good plug and three dead ones. In that case you need to prove it by taking the rail off.
In this case,  old mate reads 2800 ohms across the rail, we don't need to do separate measurements. They are all R/S

[The Gonz]

I'm happy to labour it for one more post. Total resistance in parallel is measured as
1/Rt=1/R1+1/R2+1/R3+...
To use the old plumbing analogy, this is like saying that with 4 parallel pipes and no flow, all 4 are blocked.
In a nutshell, 

[diesel1984]

You are right about pararell resistance formula. But this is not ideal method as glow plug resistance on 1st plug can be 0.25ohm, 2nd 0.5ohm, 3rd 0ohm, 4th 0.5 ohm. Glow plugs inner resistance can also be different on different outside temp and take you to wrong readings when measuring in parallel.

Good glow plug on this engine is from 0.25-1ohm.

I'm saying that again.
Take measurments with rail removed. First test each plug with ommeter and after that with continuity test. If 1 plug have too big difference from another change it.

[The Gonz]

In which case by your own figures the worst case would still yield a rail resistance of far less than 1 ohm and yet you're getting 2k8? OK, this time I'm out.

[GaryDrohan]

This is certainly the best way to test each individual plug and yes, my method will only tell you if ALL the glows are blown, any other reading will tell you basically nothing. I'm happy that 2800 ohms, 12V at the rail and no current draw off the battery is pretty conclusive all my glows are blown

But for a definite test for isolated glow plugs, diesel1984's method is the only way 

[The Gonz]

But for a definite test for isolated glow plugs, diesel1984's method is the only way 

On that important point we can agree. Oops... I'm out.

[nzenigma]

In which case by your own figures the worst case would still yield a rail resistance of far less than 1 ohm and yet you're getting 2k8? OK, this time I'm out.

@The Gonz , Mate its getting a bit chaotic up here on the fight deck, could you run those figures again? 



 

[tw2005]

In which case by your own figures the worst case would still yield a rail resistance of far less than 1 ohm and yet you're getting 2k8? OK, this time I'm out.

@The Gonz , Mate its getting a bit chaotic up here on the fight deck, could you run those figures again? 



 

It's the red one, cut it, cut it now or we'll all die