Help Please!! VW Cold Start Issues

Gavin1

Hi,
I recently purchased a 2.0 VW Golf Cabriolet. Since I got it I have installed a Clifford alarm(may not be related).

The issue is with starting the car cold. The car starts and then dies. It then takes a number of attempts and some serious right foot accelerator action to get it started. After it has warmed up it starts and idles normally no problem. It just seems to be the inital cold start.

When I open the door I can hear the fuel pump prime, I have been told that my fuel sender is knackered as it never reads full and drops to empty when it should not etc.

Any ideas as this is doning my head in as well as the ususal "I told you to buy it from a garage" abuse. Any help would be much appreciated.
Thanks

mike65

Some fuel is left in the injection system which get used the moment you start up then it dies and cranking manually draws fuel through the system. On a warm engine the fuel won't have had chance to drain away fully so if its fine on warm start that suggests the check valve is okay, you can hear the pump prime so that means relay works I presume. How old is the car?

fuel pressure regulator might be the cuprit.

The sender only measures fuel in the tank, nothing else so thats won't be a factor.

Mike.

Gavin1

Thanks for the reply.

The car is 2000.

zuutroy

I'd guess it might be your idle air control valve, or depending on how old it is, you're carb might be knackered (dunno when VW went to EFI, sorry). Best bet if you're in Dublin is to book it in to McNamara's. They're very good, if slightly pricey. It'll save you the headache of troubleshooting yourself.

crosstownk

A lot of VWs of that year give problems with the engine temperature sender. When the engine is cold it sends an incorrect 'warmer' signal to the ECU and the engine does not start - the fact that you have to give 'serious right foot' is indicative of this. The sender is quite cheap to buy - even from a main dealer. If it is faulty it wont show as fault if the fault memory is checked by a garage because the temperature reading is within the max/min range of the sensor but is wrong for the ambient conditions. Get it checked before you spend a fortune having fuel pressures etc checked which would be the next logical step.

mike65

Hmmmm, I had that problem on me old Merc and the symptoms were slightly different to described as the initial start was the bugger, once it was going twas grand. Also it was harder to start according to the ambient temp (warmer=harder). Changing the water sender fixed it.

Mike.

junkyard

Cold start injecter?

AMurphy

definitely not the cold start injector(s) as it starts.
a). The cold start injector, if fitted, is used for the first few rotations of the engine to get it started, and we are told it starts.

b). On Modern EFI systems, the cold start injector is not there, the std 4/6/8 injectors are energized in a manner as to serve the same purpose and deliver excess fuel in order to start the engine.

However, I would ask if it starts without any problems and then refuses to run normally or if it is also slow to start also.

So do you have the same number of injectors as cylinders or Cylinders +1.

Typically, the amount of gas required to start a cold and hot engine are different, but excess is required in both cases, and if it starts quickly and perfectly both when hot and cold, then I would be inclined to think the temp sensor is reporting correctly.

Does this one have a fly-by-wire throttle.

Nonetheless, I'd definitely look at the posibility of a failed or maybe disconnected EFI temp sensor, which may be seperate from the Gauge sender. Easy way to find out, How many temp sensor like items screwed into the water jacket of the engine.
disconnect items that appear to be temperature sensors and see what responds.

check youir air intake for any airleaks, cracks, split vacuum hosing, etc.

junkyard

Ok, I'll stand in the corner then.:(

Gavin1

Thanks for the responses.

I have been away so sorry for the late response.

As far as I know it does not have a fly by wire throttle.

I must check the rubber hoses. How many are there typically? There are two on top of the engine and when I compress one the engine struggles.

The start up is as follows:
Intial start fine revs very briefly and dies.
Leave it for about 10 seconds then crank it pressing the accelerator as it goes then it catches and no issues.
After that it starts on the first or at most second turn.

Kimbot

This is only if all the above is ruled out!!

Does the clifford happen to have the Remote start option??? This could cause problems like that where one of your wire is not connected correcly if I remember rightly!!

crosstownk

I'll stick with my temperature sender diagnosis - I've seen this thousands of times with VWs. If the problem only occurs when cold then it is obviously related to the temperature. If you know a garage with a VAG diagnosis machine (VAG 1551, VAG 1552, VAG 5051, VAGCOM or similar) then you will be able to see the temperature reading at start - if will be obvious if the temperature reading is wrong.

AMurphy

Gavin1 wrote:

Thanks for the responses.

I have been away so sorry for the late response.

As far as I know it does not have a fly by wire throttle.

I must check the rubber hoses. How many are there typically? There are two on top of the engine and when I compress one the engine struggles.

The start up is as follows:
Intial start fine revs very briefly and dies.
Leave it for about 10 seconds then crank it pressing the accelerator as it goes then it catches and no issues.
After that it starts on the first or at most second turn.

Just look at the throttle body, is you see a cable, it is cable if you see wires and no cable, it is FBW.
And while you are at it, check how many injectors you have 4 or 5?.

What happens if you press accelerator on the 1st attempt as you do on the 2nd attempt.

How soon after he 2nd attempt, does it have to be when it returns to normal.
ie if you simply got it running, ideling for a few sec or whatever it takes to get over the hump and switched it off immediately.
Would it restart normally on the 3rd attempt, or do you have to leave it ideling for a (much) longer while, ie till it warms a bit.

here is something you could do to see if it may be fuel supply related.

turn on teh ignition to RUN, till you hear the pump fire off and stop again.
do not turn to START, but switch it off and back on again after about 5 sec. or whatever duration it takes for the pump prime timer to reset, usually between 2 and 10 sec.
Do this a few times to initially prime the circuit.
Then attempt to start it.

if there is a change, as in it starts with no problem, you may have a fuel supply problem. If no change, we can rule out the supply side.

btw, do you know how many pumps that cas has, 1 or 2. And any problems or spluttering/dying on going up steep hills.

How many hoses, I have no idea. Just check any hose that is attached into the air intake and make sure they are not leaking or cracked, that includes the main intake hose pipe (2~3" in diameter) between the MAF and the throttle body as well.

Any semi deasent OBD tool would do to test the engine temp sensor.
and I don't think your gas gauge sender malfunctioning has nothing to do with this problem, UNLESS, it is due to damaged wiring or connectors and your in-tank pump is not also functioning.