Mis-fire... Valves? Flames!!

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barkin
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Mis-fire... Valves? Flames!!

Post by barkin »

Hi all,

Hope you can all help again, as you all seem to have been very helpful in the past...

I have an '81 2.8i cologne...

As your looking along the engine the n/s / right side seems to be firing fine (cylinders 4, 5, & 6). However there is a mis fire along the left side (cylinders 1, 2, & 3) and every once and a while there is a flame out of the exhaust from this side. There also seems to be an irregular popping sound also from this side...

We've checked the valve clearances and all the spark plugs are sparking back to the dizzy. Timing hasn't been changed however I don't have a strobe to check this. Valves looked ok when we had the rockers off...

Any idea's suggestions? All help is greatly appreciated

I'll look forward to hearing from you all.

Barkin



mfw898y
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Post by mfw898y »

Have you done a compression test?

barkin
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Post by barkin »

Not yet... I think one of the piston rings is shot as I'm only getting about 40degrees out of that exhaust port.

I can't use the tester I've got because of the angle of the engine so I'll need to borrow a friends.

I'll let you all know how it goes when I've tested. Thanks.

mfw898y
Junior
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Post by mfw898y »

If you've been running it like that since the first post, its probably totaly FUBAR by now :?

barkin
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Post by barkin »

I'm not that silly... I've been working on the body since. Thank you for the concern tho.

I'll probably be looking to take it into a garage. After having re-built the car and engine from the nuts up I'm starting to lose patience...

Barkin

Coops
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Post by Coops »

are your injectors fine?
my mate had a similar thing on his 2.8 after he started using unleaded fuel,
turned out to be valve seat recession,
double check your valve clearances and as mentioned before do a compression test.
Regards Tony C (COOPS)
Image
MS2 V3.57 Ecu mapable efi and wasted spark ignition.
Rotrex C38-91 supercharger and Cossie RS500 Intercooler @ 14psi of Boost.
Sponsored by: www.extraefi.co.uk & www.interpart.biz & www.caprisport.com
Web site: http://www.capriracing.co.uk

barkin
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Posts: 25
Joined: Sun Feb 11, 2007 1:56 am
Location: Medway

Post by barkin »

Thanks,

Injectors have a good spray, valve clearances have been checked, adjusted, checked and checked again...

I'm using a leaded additive which protects the valve seatings from recess.

When I get round to it, it'll be a compression test.

Thanks again all for your suggestions.

barkin
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Joined: Sun Feb 11, 2007 1:56 am
Location: Medway

Post by barkin »

Did a compression test last night.... I'm getting around 170psi (12bar) on all cylinders.

Took the dizzy cap off again and cleaned that up and checked all the ht leads (which have been replaced recently).

Changed the fuel filter as it needed doing and a couple of fuel lines to move the filters mounting.

When I ran it after the compression test it ran without the cold start. Revs slowly rose to 800rpm then dropped back down slowly and stalled... same thing each try.

Still perplexed as to what the problem is. Replaced pretty much everything that couldn't be tested. All it could be now is Timing, could check valve clearances again, throttle body?? Don't know. I think I've checked everyting maybe I've missed something.

Any suggestions greatly appreciated.

Barkin

Coops
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Post by Coops »

what plugs you using?
and are the leads new?
flames out the exhaust indicates unburnt fuel, along with popping.
Regards Tony C (COOPS)
Image
MS2 V3.57 Ecu mapable efi and wasted spark ignition.
Rotrex C38-91 supercharger and Cossie RS500 Intercooler @ 14psi of Boost.
Sponsored by: www.extraefi.co.uk & www.interpart.biz & www.caprisport.com
Web site: http://www.capriracing.co.uk

barkin
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Posts: 25
Joined: Sun Feb 11, 2007 1:56 am
Location: Medway

Post by barkin »

I'm pretty sure the plugs are bosch and the leads are definately new as are the plugs. We came to the same conclusion about the unburnt fuel.... but as to why we are still to determine.

For some reason the problem I have now is I've ran out of fuel so the tank will need topping up... Could have inadvertantly solved the problem last time we took it all apart tho as it ran briefly fine with no popping etc.

I'll keep you all informed. Barkin.

jamesok
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Location: Liverpool

Post by jamesok »

Check your metering head

Is the rubber shroud tight around it,check that the flap is free moving

barkin
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Post by barkin »

Metering unit is fine, sealed with free movement on the arm...

The car is garaged until the weather gets nice again, so haven't posted about it in a while...

Thanks for all your support.

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