Latest Tale Of Woe...

[AdamF 19 1 Cars]

Hey guys,

 

After a very lovely Summer of 205 GTi6 driving it appears that Winter has some curveballs in store.

 

So...

 

I was driving up a hill two days ago and put my foot down, revs got to about 4k at which point the car lost power, spluttered and the battery light kept flashing. I just about managed to get it home. It idled fine.

 

Next up was a trip to see local 205 expert (in my eyes) Justin who's a member on here and who lives down the road. We put a meter on the battery and alternator which all looked to be fine. We then removed the plastic coilpack cover and the problem presented itself, one of the coil packs had rattled loose. Easy we thought, tighten it back up and jobs a good un. We did just that and I drove home except I noticed it was now misfiring on idle but good on full load.

 

I wondered if the spark plug had been damaged so replaced it and started the car up no problems and appeared to idle properly, I then bolted on the plastic cover and went to start it up again but no joy, it would just turn and turn but not catch on.

 

I figured the coil pack was maybe damaged, so I bought a new one from ECP and replaced that but same problem. Engine wont catch on.

 

Fuel pump is priming, fuel is getting to the rail above the engine.

 

Completely baffled.

 

Help very welcome.

 

Thanks

 

Adam

[dcc 855]

CPS might be loose - 10mm bolt holding it on top of gearbox

[dobboy 231 2 Cars]

Could you not measure the resistance of the other coil packs, and see if the one you thought was goosed is actually ok? Or is it physically broken?

 

Were the others tight enough?

 

Is the wiring still ok to coil pack/plug?

[Anthony 1,003]

Should still start fine even with a totally dead coil, just on three cylinders.

 

The battery light flashing on when it was misfiring/spluttering before has alarm bells ringing for me, as a failed coil won't do that, other than it idling so low that the alternator isn't spinning fast enough to charge.

 

Obvious thing to do next is to remove one of the spark plugs and check to see if you've got spark and whether or not fuel being injected (you'll see the fuel mist being puffed out and the open cylinder will smell strongly of fuel - plus plugs should be moist).

 

I'm assuming btw that it still sounds like it has compression when cranking over - ie a whirr... whirr... whirr... sort of sound?

[dobboy 231 2 Cars]

Anthony, "whirr....whirrr.....whirrr" ?

 

Mines is more like "mahhoom....mahhoom....mahhoom" ????

 

Could it have been cutting out and bump start itself when the light was flashing?

[AdamF 19 1 Cars]

CPS has yet to be checked.

 

Spark has yet to be checked.

 

Resistance of coil packs was measured and they all came back good. Replaced plug and coil anyway as we thought there was a chance they could've been damaged from bouncing around/arcing etc.

 

Sounded like it had compression.

 

Does this sound anything like a alternator problem?

[dcc 855]

no. it sounds like a spark/fuel issue. check the cps.

[kyepan 291]

I hope adam doesn't mind me posting a little update.

 

Last night we checked the:

 

• CAS, plugged in, and solidly mounted
• Gearbox earth
• Shunt box connected
• Inner wing earth
• Sensors on the throttle body are plugged in
• Sensors on the water distribution block are also plugged in

 

Are there any more earths that i have missed?

 

What can we back probe on the multiplug to help us diagnose if it's a wiring issue in the cabin?

How can we tell if the ecu is getting power (other than we can hear it primingW

[Anthony 1,003]

If the fuel pump primes, the ECU is getting power. You should get an engine check light on the dash too if that was wired up during the conversion.

 

Obvious question is whether there is spark and fuel being injected or not.

[dobboy 231 2 Cars]

There's the camshaft sensor over at the timing belt area too.

 

The conversion wiring guide might be handy, as it also had the 16v diagram.

[kyepan 291]

From what i can deduce, it's a tidy install, all of the joins in the loom have been done at the under dash drivers side multi-plugs, with neat soldered and shrink-wrapped joins.

Ecu is mounted behind the battery...

 

Spark and fuel next, he's charging the battery today, and may be able to look into those things tonight.

[Paul_13 212 1 Cars]

Unplug and plug the double relay a couple of times. Might be corrosion on the pins.

Or get a replacement to be sure

 

Just a thought is the inertia switch still wired in?

[dobboy 231 2 Cars]

The fuel pump shouldn't prime if the inertia switch had tripped.

 

(I wont be surprised if it starts with a good battery)

[cheesegrater 43 1 Cars]

Any chance you can get it up near Aylesbury on Saturday?

[AdamF 19 1 Cars]

Hi guys,

 

Thanks for all the posts. I have good and bad news, after replacing the coil, spark plug and charging the batt for 24 hours I got it running again! The misfire on idle has gone but the same kangarooing on full load.

 

I've had a thought and a few weeks ago I replaced the rubber fuel hose that comes from the bulk head area to the injector rail. The old perished hose was 8mm internal diameter and the replacement was 7.6mm, is there any chance this could be causing a bottle neck at full load and causing the kangarooing?

[Paul_13 212 1 Cars]

Have you checked the voltage when the engine is running?

[dobboy 231 2 Cars]

Has the alt warning lamp disappeared now? Or still on when kangerooing?

[AdamF 19 1 Cars]

Ok so the latest:

 

It turns out there was a loose connection on the fuel pump kill switch which was why the engine wouldn't start and could possibly explain the kangarooing.

 

The battery light is still coming on when it feels like it, at half brightess. The heater control acts as a dimmer for the battery light which is weird. Despite that it's running ok...

[Paul_13 212 1 Cars]

Have you checked the voltage when the engine is running?

Have your checked the voltage of the alternator when the engine is running?

 

Is the fan belt tight?

[Anthony 1,003]

The battery light is still coming on when it feels like it, at half brightess. The heater control acts as a dimmer for the battery light which is weird. Despite that it's running ok...

That's far from unheard of on 205's, typically at night when you can see the light clearer as it's usually quite dim

 

Basically from what I've seen, it's a voltage drop so you've a difference between the alternator output and the interior of the car, causing the light to come on dimly.

 

Check carefully the main positive battery cable connections on the battery and alternator as this has been seen when one of those connections is going bad and about to break, and worth checking the shunt box wiring/connections too as that could cause it, but on other cars there's been no obvious reason and they've carried on for years like it.

[kyepan 291]

mine glows dimly at night when on the motorway, two separate cars, whole new proper loom... very unexplained

[Paul_13 212 1 Cars]

Didn't mean to be the bringer of too much bad news last night.

 

Your alternator is definitely on the way out.

 

The engine does sound like a tapper

 

Also I'd sort out that fan wiring loom. The positive cable was loose on the positive terminal

[AdamF 19 1 Cars]

Thanks guys, good to meet you all last night.

 

Will address mentioned problems!

 

Thanks

 

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[kyepan 291]

You just need a nice non tappy engine with some cams in now... and throttle bodies! bwarp

[cheesegrater 43 1 Cars]

And then sack the ITBs off and get a supercharger