Hmmm, think I found the cause of the misfire.....

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Kitch
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Hmmm, think I found the cause of the misfire.....

Post by Kitch » Sat May 06, 2006 6:02 pm

I've had a misfire recently.....well more than that, its actually refusing to rev hard at all when hot.

I changed amp, coil and cleaned every socket on every plug etc.

Thought I'd change the leads for some new super duper ones and took the cap off to clean the contacts at the same time, as its only year old I didn't think it would be worn.

It wasn't worn, it was f**ked.......

Image
Image

Rotor arm must have been clinging on for dear life at 7000rpm at times with a screw missing :lol:

Still, happy days! Lucky I bought a new one just incase really!

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Post by Way2go » Sat May 06, 2006 9:23 pm

Well done Kitch, I think you can safely say that you got to the root cause of the problem there! :shock: :D
1991 BX19GTi Auto

st gilles

Post by st gilles » Sat May 06, 2006 11:16 pm

It so often pays to start at the simple stuff.........I had a problem with a Rover 2000 for ages and that turned out to be a cracked Dizzy cap that tracked between two contacts. I had discounted it owing to its recent fitment from new but it was that in the end after weeks of sodding about and quite a bit of expense.

AlanS
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Post by AlanS » Sat May 06, 2006 11:34 pm

This explains why the official Citroen "book" says they should be coated with Loctite when refitted after a top end overhaul.
I'd also be looking at running a tap through the thread before I refitted the new screw too in case its damaged the thread on the way out.


Alan S
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tim leech

Post by tim leech » Sun May 07, 2006 10:13 am

Or if your lazy like me buy a new one!

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Mike P
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Post by Mike P » Mon May 08, 2006 9:54 am

Kitch,

Is that an OE part or an aftermarket part. It's just that I've never had any confidence in anything but genuine Citroen caps for years, after a car did 3 non OE caps in a row.

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tim leech

Post by tim leech » Mon May 08, 2006 10:17 am

My local citren specialist said the same thing, use a genuine cap everytime.

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Post by Ian_Fearn » Mon May 08, 2006 5:16 pm

I've replaced the cap, it has made some difference but the car still runs like a sack of sh*t
Last edited by Ian_Fearn on Mon May 08, 2006 5:56 pm, edited 1 time in total.
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Post by Way2go » Mon May 08, 2006 5:34 pm

Ian_Fearn wrote:I've replaced the car, it has made some difference but the car still runs like a sack of sh*t
I think I am repeating advice here but I believe this is down to injectors from my experience. Industrial ultrasonic cleaning (externally) will not solve sticking injectors, they need to be pulsed through the 4 spray patterns at the same time as solvent is passed though the injectors with their tips in the ultrasonic bath. A metering test then follows to ensure they each pass the same volume of liquid per unit time. If not more cleaning until this balance is achieved.

Do you know that your injectors are internally clean & balanced?
1991 BX19GTi Auto

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Ian_Fearn
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Post by Ian_Fearn » Mon May 08, 2006 5:58 pm

My injectors were put through the ultrasonic tank at work. We do not have the facilities for putting them through their 4 spray patterns.

When the engine is at anything over about 1200 revs it goes fine. The problem is its erratic idling. Its undriveable.
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Post by Way2go » Mon May 08, 2006 6:19 pm

Ian_Fearn wrote:My injectors were put through the ultrasonic tank at work. We do not have the facilities for putting them through their 4 spray patterns.
When the engine is at anything over about 1200 revs it goes fine. The problem is its erratic idling. Its undriveable.
That's your problem, you have injectors that are externally pretty but internally sh*tty.

I've been through this and the injectors when serviced by the Lucas Centre with the proper machine gave me an extremely smooth and responsive engine.

I took the injectors off the car and in to them. Just looked up my receipt of 3 years ago & the charge was £51 +vat =£58.93 total for the 4 injectors.
This has to be the most effective and instantly noticeable remedy ever applied to the car.
1991 BX19GTi Auto

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Ian_Fearn
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Post by Ian_Fearn » Mon May 08, 2006 6:28 pm

Why would the engine rev ok but not idle correctly??
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Post by DavidRutherford » Mon May 08, 2006 6:32 pm

Maybe:

When an engine is idling, it's a fine-line balancing act to keep the mixture correct, and supplying only just enough fuel and air to keep the engine running. When you rev the engine, and put it under load, the balance is far less critical. Mixtures need be less accurate, and if the volume is off a bit, then the engine will just generate a bit more or a bit less power.

I have to agree that this does sound like poor mixture control at idle.
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tim leech

Post by tim leech » Mon May 08, 2006 6:41 pm

I have some industrial strength injector cleaner Ian you can have free gratis if that will help!

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Post by Ian_Fearn » Mon May 08, 2006 6:43 pm

I think i'm going to scrap this car, its p1ssing me off to an unbelievable level.

I thought it would be the transmission that gave me the grief!

Anybody want to swap a BX 4x4 for a BX that works?
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