Intermittent Starting Problem

[ajones12 0]

Right, my new year's resolution is to get my 205 out of the garage and onto the road. It's a 1990 1.9 with 87,000 miles on the clock.

 

My 205 has been dogged by an intermittent starting problem that I want to sort out once and for all.

 

Here are the symptoms......sometimes when I go to start the engine and turn it over I sometimes get a "nnnnngggggg" noise as though something is shorting out. Sometimes the engine struggles to turn over and otehr times it turns over fine.

 

There doesn't seem to be any consistency when the "nnnngggg" noise occurs. The car is stored in my garage and doesn't really get started that often. When it does start the fuel pump seems to keep on after the ignition has been turn off - not too sure why, whether it's trying to pressurise the fuel system but the car has already run.

 

It's not the starter motor as this has been changed.

 

Any thoughts on how to diagnose the problem????

[Paul_13 212 1 Cars]

It could be the solenoid wire that goes to the starter, can cause all sorts of problems.

 

Sounds silly but is the earth present from gearbox to car body?

 

The fuel pump relay may be at fault, might be worth sourcing a replacement. (I think I have one spare )

[j_turnell 134 3 Cars]

I would check the condition of your 'brown multiplug' for the first issue, worth doing a search as there are loads of topics on this. The second problem will the the Tachymetric relay located next to the ecu under the dash on the drivers side.

[ajones12 0]

Many thanks to both of you for the replies.

 

What does the tachymetric relay look like??

[DamirGTI 329]

Like this :

 

 

It'll be down under the dash next to the steering column in the case of Jetronic car (on a Ph1 cars it's in the engine bay down the battery inside the black box) , if it's Motronic it'll be smaller yellow or brown relay next to the ECU ..

 

Damir

[Paul_13 212 1 Cars]

Like a black relay box (about 50mm x 30mm x 30mm) might have catier written on it.

 

It's located under the drivers side of the dash board near the ECU, have a look up through the cubby hole pocket near your right leg and you should see it

 

Beaten to it ^

Edited January 21, 2010 by Paul_13

[jengis 0]

Definately worth making sure the battery is in top conditioon as I have experienced both these issues, the fuel pump staying on, then not at all, getting more and more temperamental. This suggested tachymetric relay but replacement did nothing. Eventually, I got the battery fully charged off the car and it hasn't been a problem since.

[jord294 89]

Definately worth making sure the battery is in top condition. I got the battery fully charged off the car and it hasn't been a problem since.

 

totally agree with this ^^^^^^^

[ajones12 0]

Many thanks for the advice all. I'm hopefully going to get some Pug time in tomorrow (family permitting) to check these things out.

 

A colleague here suggested putting a jump lead from the negative battery terminal onto the engine block and if it starts consistently then this would point towards an earthing problem - any comment on this approach??

[ajones12 0]

Right - I've managed to get some Pug time in this morning (thanks Mrs Jones!) and have an update on the starting problem.

 

First time she fired up with no problems, left it ticking over for a couple of minutes and turned the car off. The fuel pump stayed on and I could hear the fuel coming up to the engine. Disconnected battery and gave it a charge. Conected it back up and tried starting but with no luck - I could hear a 'clicking' sound coming I think from the engine bay, but the car never turned over.

 

Had a look at the tachymetric relay. It's a Cartier model with a multiplug connector going into its base. The top is attached to some studding along with four black wires also connected to the studding. However, the back wires have been cut - is this a problem?

 

 

I've got the battery conectted and on charge and the fuel pump has been going for around 20 mins now - is this normal? Prior to today the car has last been run 2 months ago.

[ajones12 0]

Tried to start her again and had a slow sluggish turn over, next go she turned over ok and fired up and is now ticking over.

 

Given that initially it was a sluggish turn over this has got my wondering if it is either an earthing problem or maybe a power supply problem.....the battery seems ok or as someone suggested it could be the positive wire on the starter motor soleniod?

 

All I know is that it's very frustrating!!!

[DamirGTI 329]

the back wires have been cut

 

Which ones ? can you make us an detail picture of the wiring ?

 

If the wiring bit is sound , id try with another known good relay as i've had so far various problems with it .. the last time it caught on fire and it would do the whole car if i didn't noticed it

 

Damir

[ajones12 0]

The cut wires are on the top-middle of the picture and are fixed to the threaded stud using a round gold colouredspade connectors.

 

I had discounted the realy being the problem because of the sluggish turn-over, which is why I was thinking more on the power side rather than a relay.

 

Teh fuel pump remaining on is still a worry.....

[ajones12 0]

The cut wires are on the top-middle of the picture and are fixed to the threaded stud using a round gold colouredspade connectors.

 

I had discounted the realy being the problem because of the sluggish turn-over, which is why I was thinking more on the power side rather than a relay.

 

Teh fuel pump remaining on is still a worry.....

 

But the tachymetric relay could be a fault causing the fuel pump to remain on.....

[jengis 0]

On my car there were no wires conected to the stud - it is there just to hold the relay as far as I am aware - so could be other non original electrical items, alarm, stereo etc...???

 

Agree with your thinking that it is a supply problem as a good current spike is needed to work the relay propperly, and the starter clicking is a common symptom of a weak supply. But I'm no electrics expert, it's just I've been through something like this recently.

 

My process would be:

Check brown multiplug connection for corosion (as suggested by others)

Try another battery (is yours older than 4 years?)

Check alternator is working well and wiring is good (not too sure how best to do this though!)

 

erm...?

[jengis 0]

If the only problem now is that the pump is staying on, does giving the relay a light tap do anything?

 

If it is still cranking sluggish even after a charge then just try a new battery, even if its off a mates car.

Edited January 23, 2010 by jengis

[Paul_13 212 1 Cars]

If the only problem now is that the pump is staying on, does giving the relay a light tap do anything?

 

Give it a whack not a tap and you'll be surprised

[ajones12 0]

Thanks for all of the advice - it's really appreciated.

 

For my next Pug session I will look at:

 

1) The voltage drop from the battery to the starter and check the condition of the cable

2) Check the brown multipin connector

3) Check the earth from the gearbox

4) Replace the tachymetric relay

5) Fuel pump relay.

 

I'll do them in order as listed changing one thing at a time to see if anything solves the problem.

 

A couple of questions- can you get to the starter motor form under the car whilst it's jack-up or do you have to take the inlet manifold off?

- where is the brown multipin connector?

[jengis 0]

Thanks for all of the advice - it's really appreciated.

 

For my next Pug session I will look at:

 

1) The voltage drop from the battery to the starter and check the condition of the cable

2) Check the brown multipin connector

3) Check the earth from the gearbox

4) Replace the tachymetric relay

5) Fuel pump relay.

 

I'll do them in order as listed changing one thing at a time to see if anything solves the problem.

 

A couple of questions- can you get to the starter motor form under the car whilst it's jack-up or do you have to take the inlet manifold off?

- where is the brown multipin connector?

 

Bropwn mulitplug is usually under the Air Flow Meter, above the gearbox, between the battery and the thermostat. Best to remove AFM to get access to give it a good clean with a solvent/elec contact cleaner.

 

points 4 and 5 - fuel pump relay is the tachymetric relay.

 

Non of the things on your list is try a different battery, any reason for this? Also worth checking the conections to alternator are good.

 

I'm sure you will crack it soon enough.