Hi guys, i have just joined the site. I am looking for some help and advice regarding my A4 B5 1.8 20v SE. It's a 1999 model with the APT engine. The car has always felt very under powered and sluggish. It will hesitate badly when cold.

If you blip the throttle it will backfire, and you can hear popping in the air filter housing. When you attempt to rev the car it will hit about 5000rpm then start spluttering and won't rev any further, almost as if the rev limiter has been hit.

I got the codes read recently. P0130 was the only one. After the garage read the fault codes, he erased them. Immediately after this the car was running far worse than ever before. It would barely hit 4000rpm and would barely take any throttle.

I took the coil pack off and checked the condition, tested it, it was fine. I disconnected the injectors one by one and each of them made a distinctive difference to the running of the engine. This tells me that all cylinders are firing.

All plugs look similar and are evenly coloured. There is a little black soot which indicates that the engine is running rich. The recent emissions test confirms this with a CO reading of 0.18% against a maximum permissible reading of 0.20%.

The last thing i tried was disconnecting the MAF sensor. Voila! The engine is running perfectly without it! revving right through the range free as a bird! The car has more power than i ever knew it could have. It pulls like a train. It gets to 4000rpm and hits that well known 20 valve power band.

This would indicate that the MAF is at fault. The car idles perfectly with the MAF connected, but disconnected it will not idle at all. I have to rev it to keep it running. I am not 100% convinced though, because the posts i have read indicate that the car should still idle without the MAF connected.

Any thoughts on my situation would be much appreciated! Thanks, Al.