Where is EGR - Additives

[xantiagreen]

2001 xantia Hatchback 110 hdi 111k

Where is the EGR valve and how do I take it apart for cleaning can it be done from looking down at engine bay and is it worth switching it off or blanking. At the moment I don't get any signs of black smoke just average very light brown haze when flooring in 1st, 2nd, 3rd plenty of power no hesitation., idles between 1050-1150. Just thought I'd clean it up also would there be any reason for me to tinker with the MAF or should I steer well clear.

Is it advisable to use Forte or BG244k or stick with Redex/Wynns/STP/Millers every 6 - 12 months.

Thanks in advance.

[wellad]

The EGR is straight back from the filler cap. It's not that easy to remove and clean, access is not fantastic. It shouldn't affect idle at all, but yours seems quite high, idle speed should be 800±30. A light haze of smoke is acceptable, and if it pulls well it's unlikely your EGR is blocked. It may be more trouble than its worth blanking it, that can cause other issues. You can however remove the vac pipe going to the EGR for an easily reversible blank. You can find the vac pipe connected to the EGR as a rubber hose, pull it off and plug it with a suitable bolt. This stops the EGR operating, but won't do much if the EGR is stuck open. It doesn't sound like this is a problem in your case though.

I believe tinkering with the MAF is not advisable, with the risk of breaking the thin filament. I wouldn't suggest anything more intensive than a spray of carb or brake cleaner with it off the engine and allowing it to dry. A problem I've heard of is a poor earth going to the MAF sensor also, which results in a slightly low reading. You can check with a multimeter that resistance from pin 3 on the plug to the battery earth is as close to 0 as possible.

Really, the best advice I could give is if it's not broke, leave it alone!

As for an additive, most guys I know use dipetane. I haven't used any, although I do fill the tank with a 90/10 diesel/petrol mix once a year before the NCT smoke test and give it a good hard motorway run keeping an eye on oil temperature to burn off any soot or carbon.

[xantiagreen]

Thanks for replying, How do I get the rpm's attended to and the 90/10 mix is that diesel first then petrol, and what's the advantages and dis-advantages of that.

Thanks

[Northern_Mike]

All putting petrol in it will do is reduce the temperature it burns and and won't do any good at all. I've put petrol in with veg oil to thin it in winter (don't run yours in veg. Hdis don't like it) but never in a HDi.

Some people swear by Forte fuel system cleaner every so often. I've never used it or Redex but I've I've never had a problem.

Sent from my GT-I9300 using Tapatalk

[isisalar]

I've found that Slick 50 fuel system treatment is very effective as far as additives go, have used it many times. Gave the HDI a dose a couple of months ago, combined with some spirited driving and as expected performance improved immediately tailing off a bit as it was used up.
Interestingly, I used Shell V power, and, as an experiment, have continued to do so ever since. The performance is improving with every fill as if the continued use is slowly but surely cleaning everything up, seems more economical too.
Journey home last night it went like a rocket.
I'll be continuing the experiment.
Cheers
Paul

[wellad]

Thanks for replying, How do I get the rpm's attended to and the 90/10 mix is that diesel first then petrol, and what's the advantages and dis-advantages of that.

Thanks

The RPM has no manual adjustment, it's all ECU controlled, so you possibly have a bad sensor or a fuelling problem. The EGR doesn't affect idle, but it could cause a smokey idle. I've heard a few cases where the throttle sensor plug gets a bit corroded or gummed up, causing a higher idle. It would do no harm to unplug, clean and replug any sensors you can find anyway.

Someone into Xantias might be able to confirm or deny this, but I think the Xantias had three coolant sensors, one for the gauge, one for the ECU and one for the coolant fan relay. If the ECU one went duff, this could cause a high idle and a bit of smoke, but the gauge would appear fine. I'm not 100% if this is the setup on a phase 2 HDI.

All putting petrol in it will do is reduce the temperature it burns and and won't do any good at all. I've put petrol in with veg oil to thin it in winter (don't run yours in veg. Hdis don't like it) but never in a HDi.

Would petrol not burn hotter Mike? I was under the impression petrol was more inefficient as a fuel, and generates heat as wasted energy (good for burning off caked in carbon, bad for the MPGs). I figured this was true since diesels take an age to warm up compared to petrols. I haven't done before and after tests, but I consistently score 0.1 / 3.0 m³ on the smoke density test using the petrol

[xantiagreen]

Sorry my mistake checked the RPM and its it is bang on 800rpm, I do get a very, very small amount of light haze on idle occasionally would that be because of the 5/30 total oil used should I have gone 10/40 total, previously owned 2.0 16v xantia 1997 hatch and I used millers 10/40 never had a problem with smoke or consumption, not that the HDi is consuming any (dipstick level is the same as it was back in oct last year.)

So I should steer clear of adding small amount of petrol to tank? My biggest fear is I'll be causing more problems in the long run as this car only does the school run and after club run total of 11 miles a day 2 in the morning and 9 miles in the evening then its parked up ready for the next day. Any ideas to help prolong life of this beaut.

Thanks to all..