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A real diesel dilemma

I took the astra to the vauxhall dealer for fault diagnosis yesterday as the spanner light had been occasionally illuminated.

The technician determined that the air mass meter was the culprit, he removed it and showed it to me, and I noticed that the internals were all covered with a thin film of oily dirt, presumably blow-back from the crankcase breather.

A new one costs about £200, but after looking at it a bit more, and some paperwork, the service manager declared that it is a known fault and hence they could replace it with the modified version under warranty, even though the car is technically out of warranty (but only just).

The bad news is that the recommended procedure involves upgrading the ECU software, which I had made it clear before must not be done without my permission. He asked me whether or not I wanted to have the job done. I asked whether or not it would work without the software update, but understandably he didn't know.

I'm not willing to have the software upgraded after what heppend to the petrol astra's driveability and performance, therefore I have only two options to consider

1)I've heard that careful cleaning of air mass meters can sometimes fix them. Is this true? 2)I could ask them to try the new part without the software update, but if it doesn't work I might have to pay for their time.

Or should I just put up with it as it is, given that it doesn't seem to be suffering from poor performance.

The Dervboy

Reply to
DervBoy
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go with the software update. They wont tell you this but it would be possible to upload an older upgrade if they have it to hand. Generally though the upgrades available now are far better qualitty than they were a couple of years ago. I assume the upgrade you had done on the last car was a petrol ecotec.. XEV engine which *never* worked well anyway ( not until very much later in life ).

The air mass meter is a common problem and the bane of all cars

You can clean it - meths, or some other solvent and cotton wool buds. Its not always successful and more than often only a temporary solution.

They are giving you the modifed MAF for free, take it while you can - dont worry about the s/w upgrade, the adaptive learning will take up the slack. If you leave it it'll only get worse, and then cost you £200. The new part is obviously designed to work with the new software, so running old s/w with new part would probably not work too well.

Reply to
Mark Craft

Have you had it reprogrammed or something????? If so ring the company that did it and they might re-do it for free (or a labour only charge) after the fix

Reply to
Tim S Kemp

No, it's standard at the moment. As was the petrol astra. The "upgrade" made things far worse on that than the original software. Then they told me there's no way to go back to the original software.

That's why I don't want it upgraded.

The Dervboy

Reply to
DervBoy

Twas Fri, 25 Jul 2003 16:37:55 +0100 when "DervBoy" put finger to keyboard producing:

If it ain't broke.....

-- Regards. Mark.(AKA, Mr.Nice.) ___________________________________________________________ "To know the character of a man, give him anonymity" - Mr.Nice.

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Reply to
Mr.Nice.

It is, that's why he has taken it to a garage to be looked at..... ;-)

Anthony

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Reply to
Anthony Britt

Twas Fri, 25 Jul 2003 21:17:59 +0000 (UTC) when "Anthony Britt" put finger to keyboard producing:

He said he's got a light lit up but it's not affecting performance... how broke could it be?

-- Regards. Mark.(AKA, Mr.Nice.) ___________________________________________________________ "To know the character of a man, give him anonymity" - Mr.Nice.

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Reply to
Mr.Nice.

The ecotec engines work fine, they just have a crap management system. They work very well when fitted with multiple carbs...

The adaptive learning you speak of deals with fuel mixture and ignition timing (both of which are irrelevant to a diesel as it has no lambda sensors nor knock sensors).

The problem is with the "driveability features" in the newer vauxhall software. These include: Disabling overrun fuel cut-off completely when cold and below 2000rpm when warm, thus no engine braking under these conditions. Addition of a delay between removal of throttle and the overrun cutoff becoming active.

In the 1.6 astra (Z16XE?), there was also reduced performance below 3500rpm and increased fuel consumption after software update. You should have seen the rolling road plot - there was as much as 6bhp jitter beween 100rpm points. Yes, thats right, power would actually *decrease* by up to 6bhp when the revs had *increased* by 100rpm. After the superchip upgrade it was smooth again, but the "driveability features" remained.

My fathers cavalier (X20XEV) also needed a new air mass meter a few months ago. It too was given a software update. It ended up withe the same features as the Astra, just much more severe. On that the revs hang for 1-2 seconds after the throttle is lifted.

It's clear from these cases that vauxhall have recently employed some incompetent geeks for writing their software and engine maps, so one could assume that the diesel software will be equally bad. Hence my reluctance to have a software update.

This crap software is the only reason I sold the petrol Astra and bought this one. If the same happens to this car I'll hate that too.

That's what I thought, but it's got to be worth a try without the software update, provided that they'll allow that.

One things for sure though, I'll never buy another vauxhall as long as I live! In future I'll just buy classic[1] cars.

[1] Old bangers which have carbs or mechanical diesel injection systems.
Reply to
DervBoy

Twas Sat, 26 Jul 2003 17:15:35 +0100 when "DervBoy" put finger to keyboard producing:

That sounds like the way to go. If the software update causes problems could you speak to a company like superchips about redoing it?

-- Regards. Mark.(AKA, Mr.Nice.) ___________________________________________________________ "To know the character of a man, give him anonymity" - Mr.Nice.

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Reply to
Mr.Nice.

As an aside, both the Ford TDci's and renault DCi's and some PSA Hdi's do use knock sensors, slightly different to the petrol engine sensor, but used by the ecu to reduce diesel knock in its adaptive learning function by altering injection timing slightly from its preset map.

Tim..

Reply to
Tim..

Well, if you've ever heard a vauxhall DI (excepting the new CDTI) you'll realise that they have no knock control system :-)

When a neighbour first got his Vectra DI, it used to wake me up every morning! The neighbours must be going potty now there's two of them about :o))

-- The Dervboy

Reply-to address is valid as required by my news server, but is a spam box and is never read. My real e-mail address is thedervboy{at}btopenglobe{dot}com (substituting "globe" with "world").

Reply to
DervBoy

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