HELP!!! lack of power

[evie]

hi i posted a thread a while ago, i lose power momentarily and it (1991 1.3lx maestro) almost miss fires when i accelerate. not to bad when cold but gets worse when warm.this is what ive done so far.new plugs.leads.rotor & distributer cap and all filters and oil etc.new vacume pipes alround, stripped carb down cleaned and topped up dash pot. removed ,cleaned distributer and reset timimg. still no joy this just started late last year . car isn.t used much am now wondering if it could be a crack in the head but this only happens when you put your foot down and after it has settled it is ok so not sure about head any suggestions please as my wife will not drive "evie" any more and wants me to scrap her but i'm getting attached now and don't want to break her. thanks mick!

[awol]

Were any of the new plugs, leads, rotor, dissy cap fitted PRIOR to the problems? its not unknown for them to be faulty. the other thing id check would be the connectors on the coil, or perhaps a different coil. im not sure what else to check, but ill have a peruse of my tech info and see if i can find anything else.

could even be sticking valves - how many miles is it on? - a de-coke could help, though obviously that involves taking the head off.

also, i've NEVER known an A+ series head to crack unless heavily modified. head gasket might cause it perhaps, but taking the head off and having a look may not be too bad, fairly easy job, and gaskets are cheap..

[G Force]

Hi, Mick. Have you been able to set the air / fuel mixture setting at all? The symptoms suggest that the mixture setting could be lean. If you dont have access to a CO meter (gas anyliser) then you could give the following method a go.

Slowly turn the CO adjusting screw anticlockwise until engine speed drops and stumbles, screw the CO screw clockwise until engine runs its fastest. Then turn CO screw anticlockwise until engine speed just slows slightly (turn screw very slowly and listen to engine note carefully). Then turn CO screw clockwise no more than half a turn from this point to achieve the smoothest fastest idle speed.

A compression test will tell you if the head gasket has gone, usually if the gasket goes it will fail between two cylinders usually 2&3 (but not always) so both of these will show up low.

Other things you could look for are, Check and set valve clearances, Check the carb damper rod is not bent. Check for inlet manifold air leaks. Check vacuum advance diaphragm is not split.

Regards Gary :)

[nicksmaestro06]

My maestro does exactly the same thing my maestro is fitted with an automatic choke which i think may be the problam wen i put my foot flat on the accelorator if studders and takes a while to get any power so i think when i fit a manual choke it will fix the prob

[ChrisM]

My maestro does exactly the same thing my maestro is fitted with an automatic choke which i think may be the problam wen i put my foot flat on the accelorator if studders and takes a while to get any power so i think when i fit a manual choke it will fix the prob
I wouldn't be so sure that the auto choke is at fault, although they are more trouble than they're worth! The first thing I would do is put some oil in the carb dash pot. That usually cures the flat spots on my A+ series cars.

[evie]

it's already got a manual choke and the oil in the carb is topped up this is why it's a mystery. i know quite a bit about cars after owning several triumphs, this is why i'm flumoxed as i cannot find the problem as i think ive checked most things apart from dismantling the head but i don't think the problem is that serious i think it's something niggly!

[G Force]

My maestro does exactly the same thing my maestro is fitted with an automatic choke which i think may be the problam wen i put my foot flat on the accelorator if studders and takes a while to get any power so i think when i fit a manual choke it will fix the prob

Hi mate, try not to give in so easy by fitting a manual choke ;) and the chances are by fitting a manual choke you may improve things but only by masking over the real problem.

The Ignition system if not in good condition can cause problems of the nature you describe, so its important to make sure the spark plugs, distributor cap & rotor arm are OK. HT leads are notoriously unreliable this weather, a brand new set of genuine leads can solve poor starting, misfire and hesitation.

On the fuel side of things the ORFCO valve sticking open and a split in the vacuum switch diaphragm can cause your simptoms. Have a read in FAQ,s on the subject and on tuning and fault finding.

Cheers Gary :)