Advice req'd on ISV

[gor123don 0]

1) If the ISV unit has failed will the engine still start and run?

 

2) When the ignition is switched on (prior to the starter being operated) does the ISV "buzz" and if so is it loud enough to hear inside by the driver?

 

3) If not the ISV what else can "buzz" in the engine compartment when the ignition is switched on and can be heard inside until the starter is operated?

 

Reason for asking is I broke down two weeks ago when engine just stopped-had to be towed home.Have checked fuel pump,injectors,plugs are sparking all ok but engine will not fire up.

Used to get "buzzing noise" when ignition turned on and engine started but this dose not occur now and engine will not start.

 

Any advice will be greatly appreciated.

[VR6 South 0]

ISV's don't usually buzz loud enough to hear. If you hold the ISV you will feel if it's running, mInd you that's not always a sign that it's working OK.

[fla 9]

buzzing might be the aux cooling pump, just to the right of the engine block.

[Erny 0]

What engine? Is your engine even trying to start? (eg if you give it a little gas will it fire up) what exactly happend when it just stopped? Did it stall? You can set you throttle bodie open alittle to bypass your isv if you want,

[gor123don 0]

The engine is not even trying to start. It just died when stopping at cross roads. Someone mention to me that it maybe failure of the transfere fuel pump in the petrol tank - is this possible? The 9A 2ltr 16valve.

[Erny 0]

You could loosen the fuel feed to the metering head and see if anything is getting up there when u try firing it up, you generally get alittle warning when your fuel pumps/filter are getting tired, the car tends to feel like it's got a lack of power like getting starved of fuel and jumpy like a missfire on full throtle,

[Yandards 0]

1. Check the fuses.

2. Check the relays are seated ok.

3. The ISV will buzz with the ignition in the run position, you can feel it if you touch it with your hand.

4. If the ISV is not buzzing then either the wiring is dead or the ECU has no power (check by looking for volts at ISV plug with ignition on)

5. With ignition on you should also hear the fuel pump run for a short while then cut out.

6. The engine will run with a broken/non functional ISV - just not very well.

7. If you keep popping fuse 18 then unplug the lambda probe plug, it's on the same fuse as the fuel pump and if the wiring is shorting out it will blow the fuse.

[gor123don 0]

Thanks to all of you who responded to my engine problem.Now to update you on my experiences in getting the engine running again.

You may recall at the beginning of September that my Corrado (1992 2ltr 16v 118500miles) engine just cutout when stopping at a crossroads and would not fire or startup and as a consequence I had to be towed home.

When home I contacted a mobile mechanic who came to the house and the first thing he does is turn on the ignition and try to start the car and of course it did not fire or start.He then :-

1) Took out the four plugs and checked they were all sparking,said there was petrol in the bores (after shining a light down them) and then replaced the plugs.

2) Took out one injector turned engine over on starter motor and demonstrated normal spray pattern-replaced injector.

3) Took off cam belt cover and checked timing -all correct and replaced cover.

4) Disconnected air duct from metering unit at manifold and squirted "quick start" directly into engine air manifold and then tried to start engine without success.(It did not fire at all)

5) Checked all fuses and pushed all relays and tried to start the engine again -no luck.

6) Finally said he did not know what the problem was .Paid him £30 and he left.

 

One week later I found another mechanic who said he had worked on Corrado's when new at a Vag dealer.He arrived and the first thing does is try and start the engine without success.

Then he says I will try one thing before trying to read any fault codes! Where upon he unclips the metering/air filter housing and lifts up sufficiently to spray "Quick Start" into the air filter. Leaving the filter not fully rehoused he turns the engine over and it fires first time and continued to idle smoothly. He then pushed the filter assembly fully home and does up the clips.He switched off the engine and restarted it five times on each occasion starting first time.

He took the car away to use for a week and check to see if he could find any sensor faults.He brought the car back last week could not find any faults whatsoever but had fitted a new fuel pump relay.He remembered that when the cars were new that they had problems with the relay but he could not say that this was the reason for my engine cutting out. Cost £123 including £18 for new relay.

 

The car seems to be running better than ever. What do you guys think will happen again? (Remember all the sensors and relays are 18 years old - I have owned the car for 11years) or is there some other reason?