Festy a little sluggish, need help diagnosing the problem?

[Click_It]

Hi guys,
I've just changed the oil & oil filter on my car as it was overdue anyhow but the car is (still) running a bit sluggish. I'll try to explain... It's worst when I start cold, bare in mind its Summer here and well over 30c / 86f most days so even cold starts are not really temperature cold, that said I always let it idle for a minute or 2 before before I take it out for the day. I reverse up my steepish driveway, nothing a festiva can't normally handle but lately I need to have 2 or 3 attempts to get up there. What happens is the car just bogs down and has nothing to give me, so I have to go back, get a run off, up the revs and go again. Most of the time after this it's okay by sometimes at a set of lights I can experience it again although rare.

It's been babied and is in otherwise great nick, new clutch etc.

So what could be the problem?

I'm thinking carburettor needs a tune personally although before I act I'd like some second opinions in case I'm totally wrong.

Could it be the plugs & leads? Or something else? I've never really experienced misfiring first hand but it doesn't feel like that, it just feels poorly tuned suggesting the carby fuel mixture needs some attention. The air filter looks fairly clean although it probably wouldn't hurt to replace it. Next time I go out I will remove the air filter and test it out, that should tell me straight away if that's the cause. But beyond these I can't think of anything else.

[Click_It]

Took it for a spin just now without the airfilter and makes no difference. Furthermore the sluggish performance is becoming quite noticeable in all areas of driving. I put the foot down and it has to think for a few moments before finally going. Feels like its momentarily flooding or something.

I'm now convinced it's just the carby needing a tune. I used to tune an old carby on my very first car 13 years ago but I haven't been near one since. Pretty rusty. How much do I have to pull off to get to it?

[JohnGunn]

Spark Plugs are often where it's at.

The most obvious, easiest, and cheapest place to start is with new spark plugs. After that, cap and rotor as a matched set. I've never had a problem that was helped by new spark plug wires, but I've heard tell they can sometimes help. If you are still short on power start working on the less obvious possible causes which, if addressed before the above suggestions, are very likely to be a terrible waste of time and money.

This happened to me just recently when I trusted a set of Bosch Platinum IR Fusion plugs with only a few thousand miles on them. They were after all the best, most expensive plugs Bosch makes and should be good for 50,000 miles at least. Big mistake. Started replacing emission components to no effect until there was nothing left to suspect but those expensive plugs. Ten dollars for 4 NKG V-Power plugs plus a pleasant 30 minutes installing them and all was well again. Those plugs were at fault the whole time. Thus my new approach to auto repair.

"Always start at the heart of the problem and work out from there, holding nothing above suspicion."

John Gunn
Coronado, CA

[TominMO]

The most obvious, easiest, and cheapest place to start is with new spark plugs. After that, cap and rotor as a matched set. I've never had a problem that was helped by new spark plug wires, but I've heard tell they can sometimes help. If you are still short on power start working on the less obvious possible causes which, if addressed before the above suggestions, are very likely to be a terrible waste of time and money.

This happened to me just recently when I trusted a set of Bosch Platinum IR Fusion plugs with only a few thousand miles on them. They were after all the best, most expensive plugs Bosch makes and should be good for 50,000 miles at least. Big mistake. Started replacing emission components to no effect until there was nothing left to suspect but those expensive plugs. Ten dollars for 4 NKG V-Power plugs plus a pleasant 30 minutes installing them and all was well again. Those plugs were at fault the whole time. Thus my new approach to auto repair.

+1 on the NGK plugs, and plug wires as well. The wires should be replaced every 100K miles (every other tuneup) on general principles; they do go bad.

I'm not really up on why the "best" plugs don't work well in all cars; I guess it relates to the characteristics of the ignition. But the NGK V-power is a good all-purpose plug.

Edit: pour a bottle of carb cleaner into the gas tank; that might fix it if you're lucky.

[MONSOON]

Fuel filter.

[Click_It]

Fuel filter.

Thanks guys, I'll take all these suggestions on board. And this last suggestion sounds like it could be a big contributor to my problem, will replace that as I have no idea when (if ever) it was last done. I'll do the plugs & leads for the same reason. $15 or whatever for some carb cleaner probably wouldn't hurt either. I know for a fact I picked up some dodgy fuel a few tanks back, I tried to rectify the problem by filling the following few tanks with the highest octane fuel available to me but it seems to have only partially fixed it. Pointing back to the fuel filter I guess. But all are worthy suggestions will I'll take on. Thanks guys.

[FestYboy]

if you find the plugs not very worn, replace them anyway, and then at least clean the cap and rotor, and then install a new (performance) coil (Scrappy had the same issue, top speed of 100km/h before i replaced the coil). having a tank of crappy gas won't be fixed by using a higher octane fuel. use what's recomended, but switch suppliers for a few tanks (different mixes of additives/detergents).

[sanjeet]

A real pain is the carb choke-breaker, this has a vacuum connection to the choke and if the diaphram fails the engine will run like dog until it warms up and you will see black smoke.

Been to the auto wreckers twice now 3 years ago and yesterday for this small but very important part, you can check it by sucking on the rubber hose, if it doesn't move its knackered.