hi i have a 1.4 felicia estate 1998, it has just gone through the mot with no advisorys so very happy with it,  appart from bareley makeing emmisions which passed in the last 4 seconds, before the mot i fitted a new center and rear exahust new plugs and cleaned out the throttle body was a bit oily, now the car is really struggaling on hills some even needing 2nd gear the clutch is slipping but its not revving up hill yet i will be changeing that in the next month, but the power loss is confusing me it also missfires/backfires for the first 5 mins in the rain/damp weather,, i know they are not the most powerfull of engines but i had alot of favorits in the passed and they had alot more go than this does,

any help or sugetions would be helpfull thankyou

If the power loss was sudden after replacing the silencers, I suspect the catalytic converter has collapsed. That would explain high emissions too. Other than that, the ignition transformer needs a thorough visual inspection for cracks, arcing burns, dirt, rust, etc.

thanks for the reply that was my thought aswell would it be worth changing the 02 sensor too ? by the ignition transformer do you mean the rail that goes across the spark plugs ? hope that dosent sound silly but this is the first car iv ever had with no ht leads so all new to me iv always stuck with older cars haha

would it be worth changing the 02 sensor too ?

 

First you need evidence it is faulty. I am against changing parts blindly. You need to hook up a VAG-COM scanner to see how it's working the sensor.

 

by the ignition transformer do you mean the rail that goes across the spark plugs ?

 

Yes.

Were they the correct plugs? since you have disturbed the ignition system recently i wouod start looking there first for your troubles.

cheers so am i will be getting it plugged in this week and yes correct plugs corrected most of the miss fire appart from first thing in the morning after rain,

cleaning the throttle body gave back some power but the main powerloss was after replacing the exahust parts

the car had a full skoda service history untill i brought it 9 months ago and have had a good read through and checked the coil and its original to the car like most parts seem to be

Do you still have the old plugs? If so, then replace each new plug in turn with the same old one, and if the running improves you've found a bad plug.

Exactly with Ken on this, I think it's ignition related.

Umm... how big are the chances that new, correct type spark plugs are faulty? Pretty much null except if you drop one on concrete or crack it from an overtorquing. I understand you are thinking about a severe misfire that led to high HC emissions during MOT, but the OP said the engine misfires only a few minutes after a cold start and only in humid weather (on 2nd thought, isn't that all the time in there? ). I hope he can recognize a smooth idle from a rough idle. If not, a video shared in here might clear things up.

Edited 22 April, 201511 yr by RicardoM

Yes, i have seen new spark plugs out of the box that didn't work properly.

its deffinetly a rough idle and when driving off the engine holds back and barely rolls foward like fuel starvation and if try to accelerate in any gear it holds back to nearly cut out then it cleares and after 2 miles its gone sometimes thers a loud backfire through the air intake, sometimes it cuts out compleatley and takes a while to restart as if no spark normally id take each plug and check for a spark not sure on how to do tihs with the coil,

im can do almost all jobs on the engine/car iv never used a garage for anything appart from mots/fault coads obviously, but as i said im not used to all the electrical side of the newer old engines

im now sure the cat is the fault on emmisions so will be ordering a new one now, maybe its collappsed as someone said before

Umm... how big are the chances that new, correct type spark plugs are faulty? Pretty much null except if you drop one on concrete or crack it from an overtorquing. I understand you are thinking about a severe misfire that led to high HC emissions during MOT, but the OP said the engine misfires only a few minutes after a cold start and only in humid weather (on 2nd thought, isn't that all the time in there? ). I hope he can recognize a smooth idle from a rough idle. If not, a video shared in here might clear things up.

 

 

Yes, i have seen new spark plugs out of the box that didn't work properly.

As have I, and Tom and I have never physically met.

 

I'm not saying that a bad plug is the cause, but most of the other common faults have been eliminated or are more expensive to find and/or fix.

the plugs are bosch super 4s brought from halfords luckily paid trade price so will get another set from a better place and see what happens

now i know the 1st mistake here is to buy anything from halfords its all usally no good and the one near me wouldnt know the diffrence between a car and push bike not one of them has any mechanical knowlege iv seen them using abook just to change a headlight bulb couldnt stop laughing at that,

 

no chance using original set they were really bad barely started the car when i brought it

Just a thought, is your car an mpi model with a coilpack on the front of the cylinder head, or is it an spi with a distributor?

its deffinetly a rough idle

That is not what you described initially. I didn't read 'the engine had a rough idle during MOT' so how would you expect for a correct answer when you missed something obvious? I wouldn't go near any MOT garage with a rough running engine.

 

Just a thought, is your car an mpi model with a coilpack on the front of the cylinder head, or is it an spi with a distributor?

Oops, it's a 1998 Felicia, so I don't think it's a 1.3 SPI since Czechs stopped making them in 1996.

Edited 22 April, 201511 yr by RicardoM

yes its the mpi with the coil at the front

and it wasnt rough idle at the mot its only first thing in damp weather i didnt mention it in original post as totally forgot about it untill i went out that day and that happend again and just decided to add it as its annoying

Other than that, the ignition transformer needs a thorough visual inspection for cracks, arcing burns, dirt, rust, etc.

Did you do that? Inspect, clean, spray with WD40?

Next use a water spray bottle and spray on and behind ignition transformer while idling and look for sudden misfire. Don't spray only a fine mist, go also for thicker streams. If you can borrow a known good ignition transformer, that is the definitive test.

ok so replaced the coil and spark plugs not much better and a new cat but wont know that untill next mot,

now loss of power on hills, random miss fire if stalls it dosent want to start again just cranks over, using oil, and a real lack of power im starting to suspect compression problems the car has 150thousend on the clock now and was owned by a old man for most of its life full skoda service history iv had it 10 months now and use it as a daily driver which seems to have maybe put too much work on the engine more than its 2 monthly shopping trips

Where are you based? If bristol, I'd be happy to let you use my compression tester. It will only take 30 mins to run a test.

iv had it 10 months now and use it as a daily driver which seems to have maybe put too much work on the engine more than its 2 monthly shopping trips

He couldn't make 150k miles just shopping 2 times a month, unless that Felicia was made in 1903. I'd say it has a normal mileage for a 16 years old car. For a well maintained car, I'd say the engine should still have decent power. But you never know what happened in the past, especially in terms of lubrication and cooling.

 

The oil loss needs more investigation since you didn't offer enough details. I guess it's not an external leak. Most often it is the valve stem seals that fail, and only then you should think of worn piston rings. If there is blue smoke out the tail pipe when you cold start the engine but then the smoke fades, it's the valve stem seals. If there is blue smoke on heavy acceleration when the engine is warm, it's the piston rings.

 

A compression test is a good start, but it won't tell you why there is low compression. Think of compression test as a generic test. The real test that tells exactly what parts don't seal is the leak down test. Could be valves, rings, gasket, cracks, etc.

 

What bothers me is that, according to your first post, all issues started after

i fitted a new center and rear exahust new plugs and cleaned out the throttle body

So before that ecerything was dandy. Do you still maintain that claim?

Edited 3 May, 201511 yr by RicardoM

Okay thanks will look into that too and that's what I was told when I got the car was going to be used as a run around but iv got to like the car now, it was okay up until that time may be some unrelated issue that just came up at that point after 2 months of owning it, no blue smoke no smoke at all I had a old 88 escorts with oil seals gone so remember that we'll lol, there is a small oil leak at sumo bit it's so small never even drips on to the drive, iv got a reasonable motorway drive tomorrow so hope it clears up

right long motorway trip yesterday has showen up blue smoke when accelerating and now its just smokeing all the time so i think its just time to give up with the car its a shame as its got a years mot and no advisorys but the mechanics words where it will struggle on the next emissions test, i cant honestly be bothered to fix the engine if i was to id drop a bigger one in but no breakers near me have all the parts needed to do that either thanks for all the help on here though would say very helpfull people on here

I hope somebody will pick that car, put new rings and valve stem seals on it and have an almost new engine with plenty of power for a small family car.

yes would be a shame to see it scrapped iv been looking into getting one for spares to sort mine out still but all i have found is a deisel model which i could have for scrap value how hard would it be to change mine over ? all parts are with the car and it starts

I don't get it. You said "i cant honestly be bothered to fix the engine if i was to id drop a bigger one".. Now you say you want to swap a Diesel engine. Is a Diesel engine your definition of 'a bigger one' ?

 

On the other hand, fixing your car has nothing to do with scrap parts. You need new rings, new valve stem seals and new head gasket. As for the tools, I guess you could borrow a rings compressor and a torque wrench. Of course, a proper job involves some measurements of the cylinder bores and pistons.