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4.0 won't start

4.0 won't start

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Discussion

Marlboro

Original Poster:

636 posts

176 months

Wednesday 3rd October 2012
quotequote all
Hi,

My chimaera 4.0 '96 has decided to no longer start.

The battery is kept charged via an optimate charger so no problem there.

Checked dist cap and rotor arm, both look ok, no worn out contacts or carbon build up.

I suspect the ignition coil.

Any tips on the best way to diagnose this?

Is the best replacement the Bosch p/n PRC 6574

Regards
Brian

swallet

448 posts

48 months

Wednesday 3rd October 2012
quotequote all
Can you give us more info - is there any life in the engine? Does it turn over? etc

Marlboro

Original Poster:

636 posts

176 months

Wednesday 3rd October 2012
quotequote all

Engine turns over fine. Can smell fuel at exhaust, guess no spark.

Sorry for lack of info.

Was on my own today so could not check ignition spark.

Just looking for a few pointers.

Appreciate your help.
Brian


slideways

3,429 posts

126 months

Wednesday 3rd October 2012
quotequote all
Do you have a spark at the plug?

Marlboro

Original Poster:

636 posts

176 months

Wednesday 3rd October 2012
quotequote all
Sideways,

As said I was on my own.

Could not check.

I need to investigate further and rule out the basics.

Thanks
Brian
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slideways

3,429 posts

126 months

Wednesday 3rd October 2012
quotequote all
Open drivers door pull a lead off hold the lead against the engine and lean in and crank you should see a spark, but you may have flooded it so you might need to check the plugs

Naybr

209 posts

71 months

Thursday 4th October 2012
quotequote all
Can you hear the fuel pump prime when you turn the ignition/immobiliser on?

Kitchski

4,366 posts

136 months

Thursday 4th October 2012
quotequote all
Naybr said:
Can you hear the fuel pump prime when you turn the ignition/immobiliser on?
And if you can't, can you hear a click from the battery area shortly after you've switched the ignition on (before cranking it)?

Marlboro

Original Poster:

636 posts

176 months

Thursday 4th October 2012
quotequote all
Fuel pump primes as normal.

Will check spark tomorrow when I'll have some help.

Cheers
Brian

pb450

709 posts

65 months

Thursday 4th October 2012
quotequote all
Naybr said:
Can you hear the fuel pump prime when you turn the ignition/immobiliser on?
Immobiliser??? My 98 immobiliser has just gone on the blink and is currently being replaced. This forum has identified a growing number of flakey original Meta immobiliser/alarms, due to age.

Worth a check. First clue is when fuel pump refuses to prime after switching on ignition.

pb450

709 posts

65 months

Thursday 4th October 2012
quotequote all
Marlboro said:
Fuel pump primes as normal.

Will check spark tomorrow when I'll have some help.

Cheers
Brian
Sorry, missed this post whil typing last comment smile

Dr Mike Oxgreen

2,572 posts

70 months

Friday 5th October 2012
quotequote all
Note that the visible presence of a spark doesn't necessarily mean that your coil is okay. My failed coil was still producing a visible spark, but I believe it's much easier for a spark to jump a gap at atmospheric pressure than it is inside the cylinder at TDC, so you may still be getting no spark when the plug is back inside the cylinder.

debaron

697 posts

102 months

Friday 5th October 2012
quotequote all

If no spark, I'd think Ignition Amplifier (attached to side of dizzy on some models - others are mounted up by the plenum front)

Coils can go but the Ignition Amps are known for it.


HTH


Ryan

Marlboro

Original Poster:

636 posts

176 months

Friday 5th October 2012
quotequote all
Hi all,

Many thanks for the help.

Took a plug out today and have a spark.(plug looked good just fouled with fuel).

So there's a spark and fuel but no life at all when turning over.

Doesn't even missfire.

Confused

Brian

grayze

693 posts

73 months

Friday 5th October 2012
quotequote all
Marlboro said:
Hi all,

Many thanks for the help.

Took a plug out today and have a spark.(plug looked good just fouled with fuel).

So there's a spark and fuel but no life at all when turning over.

Doesn't even missfire.

Confused

Brian
See Dr Mike Oxgreen comment above. my plugs were sparking bur car wouldnt start, AA'd to the dealer who replaced the coil and fixed it.

try replacing the coil with a known good one or get it to your nearest dealer to fix before you throw any more money at it.

Kitchski

4,366 posts

136 months

Friday 5th October 2012
quotequote all
A spark plug finds it harder to create a spark under compression, so pulling the plugs out isn't always a sure-fire way of checking for spark. You really want an inline-bulb tester (Laser do a set quite cheap).
The other thing it may be worth checking is your battery. I've had EFi cars before which crank over fine, have a spark and have fuel. But the battery may be struggling to generate as much current as it did in it's youth and sometimes that being the case, the ignition amp and various sensors don't get the right amount of juice to function correctly. I had one car which was sparking, priming and turning over fine. Just wouldn't start. Every now and then it'd try to catch, almost tripping over itself...turned out the spark was erratic to say the least! So I'd try either charging the battery, or better yet switching it for a known good one to see if it makes any difference. Or boost it from another vehicle. You might find it makes no difference, or it might spring into life. Just look out for any difference however small to give you clues.

Hedgehopper

1,075 posts

149 months

Friday 5th October 2012
quotequote all
Maybe worth disconnecting the battery for 30 seconds or so and thus re-booting the ECU. This is always my fall back solution when something on the TVR decides to go pearshaped....surprising how often it works.

Naybr

209 posts

71 months

Friday 5th October 2012
quotequote all
Assuming nothing else has changed, my money is on the ignition amp. A pretty common fault & not a bad idea to carry one as a spare anyway. ECU reset first is a good idea though.

PRTVR

2,664 posts

126 months

Friday 5th October 2012
quotequote all
Might be worth pulling the fuel pump relay, and cranking the engine over, might just have flooded, this will help to purge out the petrol sat in the combustion chamber, leave it for a few hours do it again and then try it with the relay back in, but if that fails it would appear to be an spark problem.

Marlboro

Original Poster:

636 posts

176 months

Friday 5th October 2012
quotequote all
Guys,

Ordered a Bosch coil today and have disconnected ECU.
Battery is on charge.

Should have coil on Monday so no fun this weekend.

Thanks for the advice.

Regards
Brian