zx wont start after running

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borriss
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zx wont start after running

Post by borriss »

anyone please... my zx 1.4i goes well untill you stop it, if you start it imediately it may go but after a few minutes it just wont start. eg going to get some fuel. i had it tested by garage and they said it needed a new single point but after fitting a gauranteed second hand one it's still the same. strangely after removing a wire/plug connected near the top of the injeactor it might go...
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uhn113x
Posts: 1161
Joined: 06 Jan 2004, 22:06
Location: Near Leeds, United Kingdom
My Cars: 1981 Dyane - on road all year round.
1982 GSA Pallas - on road April - September.
1997 ZX 1.9D Dimension.
x 1

Post by uhn113x »

Hi Borriss
You need to catch it in the act, and find out if it is a fuel or ignition problem, otherwise you will just be on the hiding-to-nothing 'diagnosis by guesswork' method - time consuming, expensive and will introduce more faults.
Is there anything (fuel) coming out of the single-point injector? Is there any spark?
Various things can fail when warm.
borriss
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Post by borriss »

thanks for the advice will do my best, I sort of figure that it thinks it's starting from cold so the choke if you call it that on an injection goes on, but what triggers that? is it on the injector body or is it in that jiggery pokery black box inside passenger side wing? anyone?
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uhn113x
Posts: 1161
Joined: 06 Jan 2004, 22:06
Location: Near Leeds, United Kingdom
My Cars: 1981 Dyane - on road all year round.
1982 GSA Pallas - on road April - September.
1997 ZX 1.9D Dimension.
x 1

Post by uhn113x »

Hi Borriss
Ther is no choke on an injection system. Enrichment when cold is done by the ECU lengthening the injection period by sensing coolant temp from a sensor somewhere.
I would do a general check on wiring, connectors, hoses, etc. first.
On my DS there is also a 'cold start injector' that gives an extra squirt when you operate the starter, but I don't think any SP injection systems have such.
borriss
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Post by borriss »

there is a sensor, temp i guess, on the top right of the radiator which looks a bit dodgy, is it possible this could be a problem, someone has covered it in silicone?
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uhn113x
Posts: 1161
Joined: 06 Jan 2004, 22:06
Location: Near Leeds, United Kingdom
My Cars: 1981 Dyane - on road all year round.
1982 GSA Pallas - on road April - September.
1997 ZX 1.9D Dimension.
x 1

Post by uhn113x »

Certainly sounds dodgy to me [:(] Wonder why they did that?
Measure its resistance when cold, and when the engine is warm. Dunno what it should be, but someone on this list will.
What, you don't have a meter? [:0] They are less than a fiver, and everyone should have one!
jeremy
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x 2

Post by jeremy »

Normally the only sensor you find in radiators is one for an electric fan which is usually near the output. Putting one near the inlet would I suppose be a fair way of getting one to tell when the thermostat opens which could be useful for a fuel injection set up. Incidentally for example BX (and I think ZX) have a fan thermostat which is about 1 inch in diameter and certainly on twin fan cars this has 3 terminals.
Most temperature sensors for temperature gauges have a single connection. sensors in radiators probably have 2 as there is no reliable earth. gauges and warning light sensors are usually somewhere around the thermostat, and I think it unlikely any fuel injection sensors are off the engine itself.
I expect there is a diagnostic plug somewhere - might be worth getting the codes read. otherwise try and find a description, work out what sensors there should be, find them, check their wiring and for example if they are temperature sensitive try and test them with hot water. If you have things like throttle switches these can fail - gaain careful testing with a meter should reveal the problem - ie you are looking for smooth changes with no jerks in action.
jeremy
borriss
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Post by borriss »

ok this is getting tough, Garage i went to said it needed new injector body and stepper motor, now I'm not a mechanic but that sounds slightly excessive considering the car is fine except when starting from hot. does anyone know if this sounds right and of any good garages/citroen specialists around london, south or otherwise?
jeremy
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Post by jeremy »

I suppose another cause could be fuel vaporisation? Engine hot - standing - heat soaks into components or pipework, fuel vaporises . . . As throttle body has been removed have all gaskets and heat shields been replaced? carburrettors often used to sit on 4mm or so of insulation with a gasket each side. Other possibilities are fuel pipes too near exhausts . .
Jeremy
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uhn113x
Posts: 1161
Joined: 06 Jan 2004, 22:06
Location: Near Leeds, United Kingdom
My Cars: 1981 Dyane - on road all year round.
1982 GSA Pallas - on road April - September.
1997 ZX 1.9D Dimension.
x 1

Post by uhn113x »

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">ok this is getting tough, Garage i went to said it needed new injector body and stepper motor, now I'm not a mechanic but that sounds slightly excessive considering the car is fine except when starting from hot. does anyone know if this sounds right <hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
Sadly, it does sound right for a garage. If you successively replace every part, charging the customer for your 'training' each time, chances are you will either cure the problem, or the customer will get fed up with spending money and go away.
Whatever happened to diagnosis?
Cynical, moi?
borriss
Posts: 7
Joined: 07 Jul 2004, 01:20
Location: United Kingdom
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Post by borriss »

thanks for the help anyhow, I'm going to try someone who's recomended in a dealer recomendations on this forum, will see how it goes.
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