Apparent MAF Fault

[chrisp]

The engine warning light on my '93 Cav V6 started flashing on, then immediately off, as I was driving. I did the paper clip test and this showed "mass airflow meter low voltage". This got me looking online for MAFs and they are still available for the V6 engine - but with prices varying wildly from as low as £15 to as high as £400!
I thought I'd investigate a bit further though, and took off the MAF and its associated trunking between the air filter box and the throttle body. I could then see that the trunking had a split in it in one of its corrugations. Clearly this was opening momentarily as the engine shifted on its mountings, letting in air which bypassed the MAF and was leading to its low reading.
So now it was an online search for a new piece of trunking . This is a specific design for the V6 (GM part number 90411203) and has some custom bends built into it and an attached engine breather connection as well. It was not available from any of the usual online sources but one source did list it - www.online-parts.co.uk - which, despite its uk web address is located in Germany. The total price quoted of £80, including shipping & customs duties made me gulp a bit, but I've gone ahead and ordered it. Although I could probably seal up the split in the trunking, it will probably split somewhere else pretty soon as I guess the rubber is getting perished. This could lead to a complete sudden engine failure on the road, so I guess £80 is a small price to pay to avoid that happening.

[Mk3alan]

Hope your new trunking is up to the job, I replaced my CD's as it had split like yours but the new one, although doing the job, in my mind it needs to be of a softer more flexible material.

Alan

[Robsey]

I would expect that any rubberized material would soften and settle with the heat and vibration of the engine bay over time.

Oddly, when I bought my C20NE corrugated rubber air intake trunking, it was from an ebay based Jaguar specialist.
Strange but true.

[ilovedmymantas]

Hope your new trunking is up to the job, I replaced my CD's as it had split like yours but the new one, although doing the job, in my mind it needs to be of a softer more flexible material.

Alan

Funny you should say that. The replacement I bought last year (with breather connection) is soft and flexible, albeit very thin. It's more like vinyl than rubber. I thought the quality might be lacking but I've still to find out.
The original had cracked at the jubilee clip and is wrapped with self amalgamating tape and is still doing the job

[vexorg]

Samco, or one of the custom pipe people, make them for the v6

[chrisp]

Thank you for putting me onto Samco and I have contacted them to see if they can help. This is opportune because I've just received an email from Online Parts to say that, although they list the item on their website, it is no longer available.
So, also, if anyone has a new or used one of these lying around please contact me. It is for a 1993 Cavalier V6, and the same trunking is also fitted to the early Calibra V6s. GM part no. 90411203
I have a picture of the existing trunking currently patched up with some sealant, but I can't remember how to attach it to this message. The "insert image" button just adds to the message and dragging & dropping the jpg image onto this doesn't work.

[vexorg]

Might be Roose:

[chrisp]

OK thanks, that is certainly the one I need - though without the corrugations of the original part. I suppose the material is more flexible. I've previously sourced the odd shaped top radiator hose for the V6 from Roose. They are eye wateringly expensive but I guess needs must. I'll try them.

[chrisp]

Induction air hose kit ordered from Roose Motorsport, though I've gone for conservative black to match the MAF sensor. It was, as I feared, eye-wateringly expensive but it looked as though I had no choice with no original parts available. Will report back when i get it and have fitted it.

[vexorg]

I seem to remember the entire kit for the v6, air and waterpipes wasn't far off £1k, several hundred anyway.

Not so much of a problem for the v6, but the turbos need better clamps as the silicon is a bit slippy and standard jubilee clips pop off quite easily.

[chrisp]

Ah well that make me feel a little bit better about the £140 or so that I've just dropped on the induction pipe kit!
This does at least include the pipes each side of the MAF sensor with one of them including a temperature sensor and the other a rather good looking stainless steel connector for the engine breather.
Looking at the order confirmation it seems these kits are made to order in the UK, so I guess the prices are not too outrageous.

[chrisp]

Well, the new trunking to connect the MAF sensor to the throttle body on my V6 has finally arrived - I think Roose Motorsport must make these items to order. Unfortunately, it doesn't really fit. Because it has no corrugations it isn't very flexible and is also slighly the wrong shape. So it seems almost impossible to squeeze it into the gap between the air cleaner box and the throttle body. I've loosened the air cleaner box to see if this helps but its air intake threads into the bodywork below the headlight so it needs to be seated on its mountings before the trunking is attached, otherwise you can't thread the air intake back into the bodywork. Ho hum! As it happens, the temporary glue and sealant repair that I made to the old trunking seems to have held quite well - I could examine it inside when I removed it today. So I think I'll just go with that for the time being. If anyone hears of a Cavalier or Calibra V6 trunking (new or used) for sale, please let me know!

[vexorg]

I'd get back in touch with them over it, for that price they should make it fit.

[Robsey]

I agree, Roose are a premium brand, with a premium price tag - not a cheap Chinese copy.

I would want a part that fits or a refund.
But, I am a tight git.

[chrisp]

I've now made the trunking fit - mainly by twisting the steel breather tube so it had better alignment with the rubber breather pipe from the crankcase that it connects to. This allowed the main trunking to sit at a better angle, and I then was able to connect it first to the throttle body and then to the air filter box, via the MAF unit, by temporarily removing just the top of the air filter box and then manipulating it back into position, taking car to make sure the filter element was properly seated. Not a simple job and, since the steel breather tube was originally glued in, and twisting it into better alignment has broken this adhesive, I'll need to reseal it with something - otherwise it's another potential leak of air into the throttle body that would bypass the MAF. That was, of course, what I was trying to eliminate by replacing my original split trunking! I'm not that impressed with this item for its elevated price, but I didn't really want the hassle of returning it, especially since I'm not convinced that a replacement would have been any better.
I'm still in the market for an orginal equipment piece of trunking, either new or used!