strange splutter 8valve

[jasonO]

i drove it to work the other night and in the morning after my shift on startup it started spluttering and running like a dog. I seems to rev ok sometimes but under load it misses and splutters and carries on occasionally stalling..Before looking into fuel filter and plugs and ignition its a strange one because when i turn car off then on it kicks back into life for a moment occasionally acting normal for a moment, I checked engine bay as much as i could and i found on the right hand side towards back of engine near the manifold a metal bracket with what looks like an earth attached to it along with a crimp to clip on to cables or maybe hoses.this is flaoating loose.It meets up with some main cables and i think it was brown.could this be the cause of my troubles.at some stage the light flashed below the temp gauge..could this be a clue

[Blitzen]

Sounds like it is an ignition problem. I would be heading toward leads then plugs.

[Jarred]

First of all, check the timing, reset it to standard, then go from there.

[VwJunkie]

Have you traced the cable to see where its from? I know the ECU has a earth to the far right valve cover bolt... Maybe you fried the ecu... would explain the strange behaviour of your car... Try trace the wire. Good luck mate, hope its less severe and a easy fix!

[h100vw]

VERY important that the earth for the ECU is solid on these. Guessing digifant Aussie delivered. Also critical is the engine earth above the gearbox to the chassis leg and battery. Seen a few of these missed during clutch changes, first start up afterwards the starter earths through the ECU with disastrous consequences.

Another favourite for missfires is the metal caps on the end of the plug leads. They are there as heat shields but I have removed them on a couple of my cars in the past without any problems.

The ECU and fuel pump relay could be a culprit as well. I have fixed them up with a soldering iron. Can't remember the number but start the car and pull them out of the fuse box one at a time til the car stalls. You'll find 2 relays that cause this. Take the covers off and check them for bad solder joints, rework the joints regardless of what they look like though.

Hope that helps you.

Gavin

[sports racer]

Another favourite for missfires is the metal caps on the end of the plug leads. They are there as heat shields

Heat shields? What are you insulating, the plugs? the engine?

The metal shield is there to isolate stray electrical impulses which can affect a pacemaker. True. One of the obscure Japanese design rules of the 80's and 90's.

[jasonO]

Its a euro scirocco (kjetronic) The earths are fine now i have ruled out vacuum leak and relays.I might try replacing coolant temp sensor before panicking about the ecu. It was the brown earth fom the engine block that had come off has anyone experienced this coming off before.I can drive it for a couple of minutes and always get to same place before problems start.cheers for ideas

[jasonO]

Brown earth wire from engine.have put it back on to the rocker cover.

[VwJunkie]

Ok, dad used to have a scirocco in germany and had the same prob, ran like **** until you turned it off and it was fine for a few minutes... Turned out to be the leads, one of them was shorting out on the block causing the engine to run on 3 cylinders... check or replace them if you can!

[h100vw]

Heat shields? What are you insulating, the plugs? the engine?

The metal shield is there to isolate stray electrical impulses which can affect a pacemaker. True. One of the obscure Japanese design rules of the 80's and 90's.

If they were to prevent stray electromagnetic emissions, maybe they would be earthed?

Gavin