Engine Sensors

ibiza owner

IBIZA Mk3 1.0Ltr MPi
m0rk said:
Inlet air temp, or manifold air temp sensor that is.....

If it's faulty it will log a fault - shouldn't be too dear at all really

Right, after more searching I am coming up with that people who have had problems with their MAF or Air Mass Sensor (I gather its the same thing?) have had a problem where it cuts the engine whilst driving then restarts the engine (if your moving along) but then you hit a flat spot at 3,000rpm and cannot go faster than 3000rpm. This seems to be the exact same problem that is happening with my car frequently now but I am at a loss to why no EPC light is showing on my dash and if it is a MAF fault why hasn't it shown up on the test equipment when I have taken it into the garage? - its all very strange. The code that was logged was an intermittent/implausible G28 engine speed sender which is totally different from the MAF pictured above.

Some people have said that if the MAF open circuits or shorts then the code goes back to the ECU and then it just reads the values of the potentiometer above the accelerator pedal inside the car just to keep the car going but wont rev over 3000rpm then (which indicates to me it goes in a 'get home mode' or 'limp mode') can anyone throw any light on this please?

Thanks.

Andy.
 

ibiza owner

IBIZA Mk3 1.0Ltr MPi
m0rk said:
standing in front of the car.

It will be on the lower right side of the engine block, very close to the gearbox - it will take it's readings from the crankshaft.

it might be worth removing the sensor & cleaning it up a bit - when mine logged that fault it was all covered in bits of steel shards that had been drawn to it. I also WD40'd all the connections I could.

best to get at it from under the car, most likely obscured by the front engine mount.

Right I finally got around to removing the G28 Crank/Engine Speed sensor. It was a pig to get to. I had to take off the whole Inlet Manifold, remove the Starter Motor and there it was tucked away and i could see it fully after I removed the starter motor from the top of the engine.

I removed it. It didn't have any steel shards on it but there looked like a dead fly and some cobweb! - I cleaned it all up and sprayed the connectors with WD40. Put all back and have been driving the car for a week without it playing up at all and now going over 3000rpm all the time now. Very Happy:D

The only outstanding thing is that when I had the starter motor off I gave it a clean and sprayed on some spray grease and what is happening is that I reckon the inertia inside the starter motor is sticking now as I seem to turn the car over and I just get whirring sounds of the starter motor and about after the 3rd time the starter motor finally engages with the engine to turn the engine over. One day I shall have to remove the starter again and clear off all the spray grease now.

Just thought I would report back just in case someone else is having the same problem. So it didn't turn out to be the MAF at all causing the problem it turned out to be this G28 Engine Speed Sensor.

Even though the problem is fixed now I have not taken it into a garage to have the G28 fault code cleared by VAG com - do you think I still need to do this or could I clear it by having the battery disconnected over a couple of days?
 

teknow

Active Member
Feb 10, 2007
138
0
Great Wyrley, Walsall
just read it properly :doh:

Looks like it was the G28 Engine Speed sensor that was limiting you to 3000rpm.

Can you confirm? Did you have any problems afterwards?

Thanks
 

ibiza owner

IBIZA Mk3 1.0Ltr MPi
just read it properly :doh:

Looks like it was the G28 Engine Speed sensor that was limiting you to 3000rpm.

Can you confirm? Did you have any problems afterwards?

Thanks


yep, glad you read it properly in the end :D

Absolutely no problems at all since - it seems that sensor must have been sending back wrong signals to the ECU and when I cleaned it that cured the trick. Wasn't easy place to get to but well worth the time and effort to clean it because it fixed the problem.

beware though because in your case it could be something else and not the G28 sensor it might be some other sensor thats putting your car into 'limp mode'

Cheers,

Andy.
 

teknow

Active Member
Feb 10, 2007
138
0
Great Wyrley, Walsall
Well - I've had the G28 sensor cleaned up and put back ...

... the car has the diff bearings replaced on the weekend - turns out the whining noise was the diff and not the gearbox but both sets of bearings have been done anyway!

Will keep posting here to let you all know the results.

Thanks to "ibiza owner" for his help (and the rest of u!) on this one.
 

teknow

Active Member
Feb 10, 2007
138
0
Great Wyrley, Walsall
Urrrgghh ....

Despite the silky smooth ride into work with my now very smooth and quiet gearbox (hurrah!) the car died again this morning ...

a beep, followed by lots of warning lights (but not EPC) and the RPM dropped to zero.

I need to get a cable and Vagcom I've decided .....

.... which cable do you buy for a 2000 Ibiza 1.4 Cool/S?? Are there different ones?
 

seatdude

Active Member
Dec 2, 2006
160
0
hi chaps, right i have the same problem i have a 1.4 mk3 ibiza vibe mpi engine , the epc light came on one day and then i drove it and it went off, so i never thought anythink of it , i went on a long drive and then stopped of at the services and then as i gone to start the car it woudent start so i put it in 1st n got it goin, it dont start after the egine is warm , i plugged my m8s vagcom in and it said its the crank sensor but i changed it and still the same its getting worse now as im driving it will cut out and ill have to start it , also it back fires , whats the problem ? what next
 
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