Golf Engine ECU?

Ebenezer_Scrooge_2

I have a VW cabriolet and it is not ticking over as it should, will not idle at 1000rm instead it cuts out if you dont keep your foot on the throttle.

I have been told by a mechanic it may be the ECU that is at fault or possibly an ecu that is attached to the carb?
I am going to vw to get a second opinion, does anyone have any idea? and will a second hand 1.6 mk3 ECU fit or is it diffrent for a cabriolet?

HELP Lots of pound signs flashing before my eyes :eek:

Browntoa

simlilar problem , different car was a dirty engine sensor on the bottom of the engine , ran like a pig , once it was cleaned it ran fine

totalsolutions

Def not the ecu. Check for air leaks at air filter and 'o' ring. Clean the maf, but be careful. Could also be the EGR.
Popped over to the tin shack but you were out.
Could be anything but you need a better rag monkey. Oil too thick to incorrect plugs/bad plug. What did the diagnostics tell you. I have a unit for testing error codes,

Ebenezer_Scrooge_2

Thanks very much guys

So the ecu is not an easy thing to damage?
i say that because when i charged the battery and reconnected it there was a lot of clicking noises when trying to start the car, (although at first the terminals were not tight).

What is an EGR?

Ebenezer_Scrooge_2

The ECU has not been tested total, but hes says "may" be that.
I dont know a great deal about cars and want to avoid being done over so to speak

raptorman

Ebenezer_Scrooge wrote: »

The ECU has not been tested total, but hes says "may" be that.
I dont know a great deal about cars and want to avoid being done over so to speak

Might be worthwhile signing up to a VW owners forum, maybe
someone there could recommend a decent mechanic in your area
who has a good reputation.

Try googling 'vw golf owners club', there seems to be lots for the different
models/years.

Ex-Spendaholic

I have a MK2 Golf cabriolet and a MK4. The MK4 has the engine management light on more often than off. Having been through the mill with this car (which I'm now looking shot of) I would suggest that it is one or other of the following:

02 Sensor - also known as the lamba sensor
EGR Valve - emissions gas regulator
Air Mass Meter

We have had all 3 replaced. The 02 sensor was replaced by a mechanic who told us that EGR valves don't go on Volkswagens. Funny that - so why do they sell them. :rotfl: My OH bought and fitted the EGR valve and air mass meter himself.

Good luck in getting it sorted.

ktuludays

have you tried cleaning the throttle body?

this is common the mk3 for causing idle problems.

get yourself over to http://www.clubgti.co.uk/forum/

there are loads of knowledgeable and helpful people on there.

just up your car details and problems and someone will be able to help.

totalsolutions

Will try to explain how it all works. The engine management is in a Closed Loop. All things working well the engine will be fine. The ECU allows fuel into the cyclinders and for this uses a look up table in the ECU memory. It must take into consideration many factors to get peak performance and low emissions, and so to do this the ECU needs infomation in and gives the correct info. out.

Lets see now, for a given speed we need to know the excelarator pedal position (Throttle position sensor) and air being drawn in (MAF), also other things like engine speed, load, air temp, water temp, engine timing and knocking under load, and what is coming out of the exhaust (o2) then the injectors fire in a small correct amout of fuel. If any sensor is playing up then the fuel going in is wrong so the engine stalls/whatever.

You need to look at diagnostics error codes (if any) if none then the ECU is with in operating limits and cannot see a problem, but you can. So try to think like an engine with an ECU (much like a computer or a human mind playing tricks).

Look at the problem from different road speeds and gears it all needs to be reviewed. If only at tickover a faulty plug or spark cable. Even the incorrect plugs fitted. Look at the parts you have had changed receintly. Change all the air filters and fuel filters. Do you have moisture in the tank? Tescos fuel? Does it only happed on an empty tank or a full tank? Have a think about the fault when it happens and get back here.