Rav4 Xt5 Diesel Poor Starting In Cold Weather

[jedi134]

A 5w is a 5w when cold dave :-)

She turns over ok just does not fire up 1st time without a bit of acc pedal when cold.

After the initial start she's a happy lady :-)

[cwl]

Car starts fine now I am leaving it for a few secs more. -5 deg this morning and no problems. Temp guage never budged off minimum on 3 mile drive to work. Guage moves as expected on longer runs. Its just for last 4-6 weeks i've noticed this problem when temp is low but not freezing.

[Ramdeom]

Happy your problem solved.

A few months ago I have had my scValves in fuel pump replaced.

Problem was difficult start only in the mornings.

I had fault codes read and now I am £200 poorer.

Car starts OK now.

I have also replaced original YUASA battery(7+ years old),fuel filter and 4 Glow plugs in anticipation of a harsh winter.

Ramdeom.

[anchorman]

It could still be the glow plugs. The warm up time is dictated by the resistance in the plugs and Battery voltage relationship.

[spedo]

Providing your Battery is is in good condition I may suspect the glow plugs are getting tierd. For your plugs to work properly they need to glow properly, when I say properly I mean glow from the tip first. To test them take them out and apply Battery voltage and observe them glow at the tip and work back. If they glow from the middle first, do not glow at all or are slow to glow then bin them. The clue to your problem is the fact that a second warm up is needed to start the vehicle. This is how it works, the engine coolant temp sensor reads the resistance from the engine block water temprature and the ECU uses this data for the glow plug duration normally via a relay which may be a timed relay or even a separate electonic unit.

[cwl]

Thanks for all the advice. I will test the glow plugs first chance I get and let you know

[spedo]

Cwl

Be careful when removing glow plugs, it is best to spray some WD40 around them for a couple of days especially if you have not had them out before. Whatever you do don't go at them as if they were a spark plug, or you may snap them and you will then have a whole lot of other potentially expensive problems to deal with if the thread gets stuck in the head. Remove them slowly and use more WD40 if needed, then ease the the thread backward and forwards if they are sticking.

[cwl]

I've had my glow plugs out now. They came out without any dramas. When I tested them they glowed from the tip and took 4-5 seconds to glow red hot. I also checked how long the power went to them during cold starting. The power only stayed on while the glow plug heating light was illuminated on the dash. This was about 2 seconds (1 deg outside). In conclusion, The glow plugs are not on long enough to get really hot, however if I leave it for about 5 seconds after the light and plugs go off the car will start. It must be residual heat from the plugs being sufficient to warm the chamber. Any thoughts?

[shcm]

Personally, I would have measured the glowplug resistance while they were out.

I'd also check what the engine management system thought the coolant temperature was via OBD.

Here's some pdfs for you:

preheatcheck.pdf

gplugres.pdf

[spedo]

I looks like the glow plugs are ok, at 1 deg the glow plug duration does not need to be too long at all, although it is possible the engine coolant temprature sensor is not reading back the correct resistance value back to the ECU. Did you notice any pitting on the heater plug elements? If you see any burning or pitting your problem may well be an injector leak or poor injector spray pattern. It may be a good idea to have a leakback test carried out. Your fuel heater located on the top of the fuel filter may also be at fault so chek the security of any wireing, you will need an ohm meter and a hand vac pump to test this component. To check your fuel injectors in situ the engine must be at 20deg C you should have 2.5 to 3.1 ohms between each of the injector terminals.

[cwl]

Whatever the problem was, it has disappeared as fast as it first appeared. Its not just the warmer weather because the problem was there at 10 -12 deg and now it works ok at lower temps. Barring an intermittant fault with the electrics etc could the fuel quality be a factor?

[igormus]

Whatever the problem was, it has disappeared as fast as it first appeared. Its not just the warmer weather because the problem was there at 10 -12 deg and now it works ok at lower temps. Barring an intermittant fault with the electrics etc could the fuel quality be a factor?

the fuel quality is a part of problem chain always. it is like to feed a child :)

[Gods_gift]

Whatever the problem was, it has disappeared as fast as it first appeared. Its not just the warmer weather because the problem was there at 10 -12 deg and now it works ok at lower temps. Barring an intermittant fault with the electrics etc could the fuel quality be a factor?

Mine was a pig to start when it was really cold and gave that small cloud of smoke that smelt carbony (not sure how to describe it) I swapped the glow plugs and I'm not convinced it has totally cured it (sometimes occurs and as you described intermittent). Mine as it's a 56 plate doesn't have push button start but a normal key, I found if I gave it a touch of throttle and turned the key it would start so I think it could be injectors maybe or initial fuel pressure maybe even condensation in the cylinders when cold hence the white puff cloud once it starts. Don't think it's fuel related as it's done it on Shell and Tesco fuel.