Zed's dead boys and girls. ECU reporting error codes 12 and 53. This is the MAS sensor and the right hand O2 sensor.

 

Car starts, stumbles a bit, then dies. Throttle doesn't appear to do much apart from make it die quicker.

 

Now I have had all the boost stuff off on the right side to fix a water leak. When I put it all back on, car was fine for about 100 miles then died. Car was reporting just an error code 53 at the time so I presumed I'd left a leak in the intake side. I've just had all this off again this morning and put it on again but the problem's still there. And the error code 12 has just appeared as well.

 

Any thoughts? And any MAS sensors out there?

MAFS are like rocking horse shite. :(

 

They are used as an upgrade by the 200 boys, and I gather the scoob boys use them as a more reliable replacement than their stock one.

 

Have you tried getting a multimeter on the ECU loom to make sure there is continuity for the MAFS?

 

Perhaps timmy's mouse has moved in to your bay.

 

Or try resoldering hte hotwire if that fails, MACs and a 200sx mate of mine went and they jsut resoldered the hotwire AFAIK, perhas ask the MAC.

Cheers mate.

 

The car's still doing the same, stumbling and hunting while idling then cutting out. But the ECU's now reporting 55, i.e. no error. ???

Hi Mike,

 

The error codes you did have would not cause any stumbling problems, if you disconnect the mas and the 02 sensors tick over should be in the main uneffected, look for other causes like a cylinder not firing could be a bad connection at the ptu or such like.

 

If you want any further help give us a bell after the bank holiday and will talk you through a few things whilst your in front of your engine, it tends to make more sense that way.

 

 

Jeff TT

 

07974 051196

Cheers Jeff

 

I agree entirely with what you're saying. The error codes would not cause the engine to stumble as it was. If the MAF was deemed faulty by the ECU, its data would not be used and the engine would not go above 2500rpm, etc.

 

However, it now appears that it is the MAF sensor after all. It was only that one time that I got the error codes. And, at the time, the engine was sometimes running ok for short periods. After that I wasn't getting the error but the car was running like a whore.

 

Your advice was invaluable though as it got me thinking. So I just disconnected the MAF sensor and problem solved, in a manner of speaking. Car's not running above 2500rpm and is underpowered etc, showing all the symptoms of a totally failed MAF. But, it now idles and doesn't stumble and stall. When I reconnect the MAF, the idle's all over place and it eventually dies on me.

 

So it appears that the MAF was not giving readings that were out of limits (apart from the once when the error code appeared) but was giving readings that were very inaccurate. Hence the error code not appearing and therefore the car continuing to use the MAF's erroneous data.

 

So, anyone know where I can get one or how to fix one?

Aha! Mike you have found the intricacies of the zed engine and its ability to perform scientifically impossible acts!!

 

The mas I assume now was not been ingored by the ecu as is usually the case when outside certain parameters but was somehow corrupting other signals, have seen other parts of the zed engine electronics do this, that way they appear to be working ok but are corrupting signals to other sensors etc and it can lead to some very strange faults, the ConZult system is very good at picking these interference signals up mistakenly but if you know how to identify their presence it helps to identify which sensor is causing it.

 

This is a problem vehicle manufacturer`s are well aware of, Impreza`s and Celica`s had recalls for the very same problems and lots of earth braiding and improved s(screened) sensor leads seem to have been the only answer.

 

Trouble is it seems if you take a sample of identical cars they do not all have the fault and there is no traceable reason why

 

 

Cheers

 

Jeff TT

Doh! Spoke too soon!

 

Just started it this morning without the MAF connected and the same problem's there. It ran fine for a minute then stumbled and died. Now when I start it, it idles all over the place then dies.

 

Without the MAF it should still idle, so I think I can rule that out of the equation. Also, I presume this means an induction leak can also be ruled out as the measured quantity of air is no longer being used in the fuel calculation. I.e. it doesn't matter where the engine gets its air from as long as it gets it. The fuel will be calculated from the TPS.

 

I also presume (rightly or wrongly!) that this must be a "global" problem and not due a single cylinder or bank of cylinders. Even if one is functioning it should be able to keep running.

 

 

So I'm thinking it may be:

 

Engine sensor.

Fuel problem (blockage, pressure, etc).

CAS

 

 

And I'm thinking it can't be:

 

Not head gasket or top end related as this would only affect one bank.

Not ignition as this stays fairly independant up to each spark plug.

Not TPS as I've tried it with the MAF connected but the TPS disconnected. The problem stays if I do this.

 

 

Any other ideas anyone? Getting really lost with this one.

Oh and here's some more info. When I ran it this morning, it was stumbling all over the place. A sure way to stall it was to press the accelerator.

 

And, thinking about it, it can't be the CAS if pressing the accelerator affects it. Doesn't sound like an ignition or timing problem. Sounds like an air/fuelling problem. But then again, what do I know?!

Help!