306 Hdi Air Flow Meter

[Rob Turbo 3]

Just picked up a 2001 306 hdi fairly cheap, it's a bit rough but it was cheap enough!

 

Got it home, plugged my pp2000 in and found fault codes for the air flow meter/air temp sensor, checked it and it wasn't plugged in, with it plugged in it's flat as a fart, unplug it and it flies! Investigated the management light, it was taped over , Now the bloke I got it off seemed open enough about the faults with it so he may not have known about it himself (probably did though), I didn't notice the AFM plug when I was looking under the bonnet, I wasn't really interested TBH, it drove ok!

 

Anyhoo, seeing as though it seems fine without the AFM, will there be any difference with a new one on and connected up? I'll be getting one, only about £30 IIRC, but not for a few days at least.

 

The airbag light was taped over as well though, and there was no faults with that, the light goes out by itself just fine!!

[Anthony 1,003]

Does it rev and boost fine with the MAF unplugged then?

 

On mine (99/V on Bosch management) it won't rev beyond 2200rpm with the MAF unplugged when I tested it a week or two back for Hexhamstu on here who's having problems. His (also a 99 IIRC) has a MAF code logged and does the same as mine with or without the MAF connected.

[Rob Turbo 3]

Yep, with it unplugged it drives perfect! It's a 3 plug EDC15 ecu, maybe that makes a difference? With it plugged in it revs still, but it's very flat, as if there's no turbo.

[pug_ham 244 3 Cars]

I'm sure I drove mine with the MAF uplugged before when I was trouble shooting a sudden drastic increase of black smoke & it drove fine, just like normal in fact like you say yours does but mine is also a single plug ecu like Anthony's.

 

Check the plug for any broken wires pushed back pins, iirc because of the awkward location of the plug this has been known to happen which could explain why it sulks when plugged in but is fine without.

 

I have a three plug professionally remapped ecu for one of these thats no good to me if you're interested?

 

g

[Anthony 1,003]

I'm sure I drove mine with the MAF uplugged before when I was trouble shooting a sudden drastic increase of black smoke & it drove fine, just like normal in fact like you say yours does but mine is also a single plug ecu like Anthony's.

Are you feeling sufficiently intriged/bored/enthusiastic to pop outside and try it? Don't even need to drive it - just rev it at idle will suffice.

 

If yours does behave itself with the MAF unplugged, I wonder if that points at a second, non-critical sensor failure on my own car?

[Rob Turbo 3]

After I found the problem I did a google search and found someone else describing the same problem, someone suggested unplugging the MAF, when they did it ran fine, so they replaced the MAF, but I remember a while ago, a neighbor had a hdi partner van, an 02 I think, that went flat, he unplugged the MAF and it stayed the same, but replacing the MAF sorted the problem, so it seems a bit random weather your car will run without it or not!

 

I've ordered a new one, I'll report back when I get it.

 

How much do you want for the ecu? I was planning on doing my own remap but it seems it's already been done, I don't know how good the map is, I haven't had chance to put it to the test!

[pug_ham 244 3 Cars]

quote name='Anthony' timestamp='1311868214' post='1184339']Are you feeling sufficiently intriged/bored/enthusiastic to pop outside and try it? Don't even need to drive it - just rev it at idle will suffice.

If I'd seen this earlier i wouldv'e done but to late now.

 

I'll try it when I get a chance next though.

 

How much do you want for the ecu?

Ermm, duno, I'll think abut it over the weekend & let you know.

 

This remap was done by a company in northampton iirc, can't think of the name atm but I'll post it when I do.

 

I removed the ecu in the unlocked state but haven't been able to test it definately is unlocked, although I've no reason to believe it isn't.

 

g

[Rob Turbo 3]

Another twist to the story!

 

I was talking to the neighbor that had the partner van the other day, he gave me his old MAF, he said he didn't know why he kept it, but I put that on my car and it runs spot on! Engine management light is out and no running problems at all! He said it was definitely the problem on his van because after changing it the problem went, he still used the van while it was broke, and tried it both unplugged and plugged in, so can't have just been a bad connection.

 

Then the next day the brand new one came! I'm going to put the new one on just to make sure it works, then put it back in the box to keep as a spare!

 

Also did myself a bit of remapping, first I did one to give it a bit (lot!) of poke, then another with less than standard at low/mid throttle, but a little bit extra at full throttle and over 2.5k, so I get better MPG while pootling about and a bit of extra performance when I want it!

[Flozman 4]

Believe it or not I'm having HDI nightmares also, bought a Xantia 110 HDI the other day.

 

It started with feeling a little slack on the way home, no throttle response. NO power whatsoever in 1st> 2nd nothing until 3000rpm and huge surge for 500rpm> 3rd, 4th, 5th pretty flat but went. Ha ha I thought its got a boost leak no worries...how wrong I was!

 

The next day I went to see my brother at "the Garage" to use the diagnostics and it spat out some random codes P06060 P1112 "whatever" of more interest to me was the live data which showed it was down on turbo pressure (expected) but also the fuel pressure was down.

 

Anyway I did a google and it came out with many people having the same problems with endless possible causes. Great. First things first I sprayed all the charge pipes with a fairy liquid solution and found a small leak at the at the join with the inlet manifold.

 

Just to make sure I pulled all the hoses off and took them up to the Lab (kitchen) for pressure testing (blowing down one end whilst covering the other) I replaced all the the hose clips with new items and sealed the leak at the manifold. Sorted I thought, the test drive revealed that 3 hours in the dirt working was hardly worth it.

 

Next up was the EGR, seemed to be working fine so I chucked it. > Vac pipe to the turbo is also fine. So we have boost pressure for sure.

 

I pulled off the plug out of the MAF and the engine light came on and the 2100rpm limp home mode. I cleaned the wires in the MAF with some alcohol and cotton buds and managed to break them doh! Which is a shame as it looked like the original factory unit. I thought what the hell lets see if it does anything, on start up it will rev normally for a few seconds until the ECU see' the damage and bumps in the limiter so I had a few sprints up and down the road and managed to hit 3rd gear once suddenly WOOSH huge surge of speed a 3000rpm and gone again.

 

So I'm after a MAF tomorrow from a reputable brand and Ill see of that does anything, but I have a feeling this will not cure my overall problem. God I wish id got a XUD!

[feb 47]

They are not that bad (compared with e.g. Bosch ones Japanese cars use)

http://www.ebay.co.uk/itm/CITROEN-XANTIA-2-0-HDi-MASS-AIR-FLOW-METER-SENSOR-MAF-/110644248782

I know it's too late now but you should never touch the MAF wire, just clean it with brake cleaner if needs be (others say that even that should not be done).

[Flozman 4]

They are not that bad (compared with e.g. Bosch ones Japanese cars use)

http://www.ebay.co.uk/itm/CITROEN-XANTIA-2-0-HDi-MASS-AIR-FLOW-METER-SENSOR-MAF-/110644248782

I know it's too late now but you should never touch the MAF wire, just clean it with brake cleaner if needs be (others say that even that should not be done).

 

Vielen dank, I cant really wait for it to be posted from ebay land, the last time I bought the cheapest Air flow Meter off the net for my old Merc C200 it didnt work! This was to get around the Slightly pricey Bosch unit which I think was something like £170.

 

I have never tried to clean one before It was just a move of desperation, had it not been after 5pm id have bought one from the local auto factors just to eliminate it from the list of suspects.

 

I hope it will help but I suspect a more serious fault.