Any car mechanics

[Nosevi]

My guess would be that it's not actually the battery, and it's either condensation in the coil, connection between coil and HT leads or connection between HT leads and spark plugs.

When you start up the moisture prevents a good connection somewhere causing the car to run on less cylinders, when it warms up the the moisture is dispersed and so the connection is made and the car runs on all cylinders. My bet is in the top of the coil if it keeps doing it as moisture is more likely to be trapped in there and so re-condense when the car cools down. Good squirt of WD40 on both ends of each HT leads and open up the coil and give it a good dry out and you should be firing on all cylinders again!

I'm not a mechanic but I own an Italian car - if you don't 'get' car electronics it can get pricey keeping them going

And I apologise unreservedly for that "firing on all cylinders" pun.....

 

[Nosevi]

Sounds like an electrical problem. It maybe that there is damp getting into the HT system that is Ok when the car has warmed up.

Bingo - was typing over you. I guarantee this will be the snag. The lumpy running is a misfiring cylinder causing the engine to run out of balance. Easy way to check, unplug the HT leads one at a time - unplug one that's working and it'll get worse or the engine will stop, unplug the one which isn't and there'll be no difference. You can also check for a spark by holding the HT lead close to the cylinder block while the car is running to see if it sparks (but be careful as it'll give you a bit of a jolt if it get you instead of the cylinder block).

 

[Fish]

My guess would be that it's not actually the battery, and it's either condensation in the coil, connection between coil and HT leads or connection between HT leads and spark plugs.

When you start up the moisture prevents a good connection somewhere causing the car to run on less cylinders, when it warms up the the moisture is dispersed and so the connection is made and the car runs on all cylinders. My bet is in the top of the coil if it keeps doing it as moisture is more likely to be trapped in there and so re-condense when the car cools down. Good squirt of WD40 on both ends of each HT leads and open up the coil and give it a good dry out and you should be firing on all cylinders again!

I'm not a mechanic but I own an Italian car - if you don't 'get' car electronics it can get pricey keeping them going

And I apologise unreservedly for that "firing on all cylinders" pun.....

Bingo - was typing over you. I guarantee this will be the snag. The lumpy running is a misfiring cylinder causing the engine to run out of balance. Easy way to check, unplug the HT leads one at a time - unplug one that's working and it'll get worse or the engine will stop, unplug the one which isn't and there'll be no difference. You can also check for a spark by holding the HT lead close to the cylinder block while the car is running to see if it sparks (but be careful as it'll give you a bit of a jolt if it get you instead of the cylinder block).

Thank you, I did say to her I thought it could be plugs as when I drove it back to her works it didn't seem to have any poke, especially in 3rd gear.

I'll take her into work tomorrow and then have a play with what you suggest on the beast, I'll still have her serviced though next week, I think after 12yrs she deserves it

 

[Fish]

I'll still have her serviced though next week, I think after 12yrs she deserves it

That's the car not the wife :smirk:

 

[GreiginFife]

My guess would be that it's not actually the battery, and it's either condensation in the coil, connection between coil and HT leads or connection between HT leads and spark plugs.

When you start up the moisture prevents a good connection somewhere causing the car to run on less cylinders, when it warms up the the moisture is dispersed and so the connection is made and the car runs on all cylinders. My bet is in the top of the coil if it keeps doing it as moisture is more likely to be trapped in there and so re-condense when the car cools down. Good squirt of WD40 on both ends of each HT leads and open up the coil and give it a good dry out and you should be firing on all cylinders again!

I'm not a mechanic but I own an Italian car - if you don't 'get' car electronics it can get pricey keeping them going

And I apologise unreservedly for that "firing on all cylinders" pun.....

52 plate will have a DIS pack. Good luck opening that up.

 

[Deleted Member 1156]

Robin...if you do need to replace the battery, look for one online as it's much cheaper than the shops. I ordered a new one for my Audi yesterday, £49 inc next day delivery with a 4 year warranty :thup:

 

[GreiginFife]

Bingo - was typing over you. I guarantee this will be the snag. The lumpy running is a misfiring cylinder causing the engine to run out of balance. Easy way to check, unplug the HT leads one at a time - unplug one that's working and it'll get worse or the engine will stop, unplug the one which isn't and there'll be no difference. You can also check for a spark by holding the HT lead close to the cylinder block while the car is running to see if it sparks (but be careful as it'll give you a bit of a jolt if it get you instead of the cylinder block).

Its also highly likely that if there was a misfire in any cylinder then the ECU would throw a fault and the EML would be on. If it was just struggling through low initial charge but all cylinders were firing, albeit poorly, then no fault would be thrown.

I appreciate you have a vintage sports car but modern engines/control systems are a million miles from your fairly rww mechanical Ferrari.

 

[Fish]

52 plate will have a DIS pack. Good luck opening that up.

Robin...if you do need to replace the battery, look for one online as it's much cheaper than the shops. I ordered a new one for my Audi yesterday, £49 inc next day delivery with a 4 year warranty :thup:

:thup:

 

[GreiginFife]

:thup:

Older cars had a coil which lived in the distributer, it could be opened up and accessed for cleaning and adjustment as most adjustment was manual at the carb etc.
Modern cars (98 on) mainly have Distributerless Ignition System or DIS pack as a replacement. A very sealed unit with compurt programmed timing for your spark plugs as modt adjustments are now electronically controlled. So you cant just open it up and squirt WD40 in it.

 

[DanFST]

I don't want to guess, if I changed the battery, which aren't cheap, and the problem persistd, I'd be pretty peeved.

Then learn about cars yourself. Car repair is almost always guess work in the initial diagnostics.

I'm 90% certain It will be the battery, it needs changing anyway.

 

[Fish]

Then learn about cars yourself. Car repair is almost always guess work in the initial diagnostics.

I'm 90% certain It will be the battery, it needs changing anyway.

Why does it "need changing anyway", especially if it turned out not to be the battery?

 

[Smiffy]

Hi mate
my service manager (Nissan) says the earlier Micras can flood if you sit there pumping the throttle for any length of time while you are trying to crank it over. This would cause the lumpy running until it has cleared itself.
Battery alone wouldn't cause lumpy running but he said it's worth getting a battery test done on it.
Also, if it HAD flooded and you finally got it going again, it would most probably chuck a load of ***** out of the exhaust in it's efforts to clear itself. That's most probably what you saw.
Hope that helps
Rob

 

[Foxholer]

It's definitely worth taking the car for an extended run a few times as those short trips are engine killers!

But make sure you take Jumper Leads with you!

Battery could be on the way out but, as you say, quite pricey so worth checking out initially.

 

[Fish]

Hi mate
my service manager (Nissan) says the earlier Micras can flood if you sit there pumping the throttle for any length of time while you are trying to crank it over. This would cause the lumpy running until it has cleared itself.
Battery alone wouldn't cause lumpy running but he said it's worth getting a battery test done on it.
Also, if it HAD flooded and you finally got it going again, it would most probably chuck a load of ***** out of the exhaust in it's efforts to clear itself. That's most probably what you saw.
Hope that helps
Rob

Hi Rob, No pumping mate, even when I turned it over and it fired up first time it really rocked and was noisy and then after only a minute or 2 and just gently keeping the revs going it then ran and ticked over smooth. The wife has just returned after I dropped the car off to her at 1pm, again it was lumpy and noisy and then ran smooth after ticking over for a few minutes whilst she cleaned the screen!

Going to check the plugs, clean and WD40 all the leads after I drop her off tomorrow and see if that does anything, I'll also take her for a spin down the A45 to my club and back and open her up

 

[gripitripit]

When was it last serviced??

 

[DanFST]

Why does it "need changing anyway", especially if it turned out not to be the battery?

You have asked for advice, I have given it to you! I'm assuming you know nothing about cars from your posts, so i'm trying to make it as simple as possible

Your battery won't be hold anywhere near the amount of charge a new one can. As such you are having the problems you stated in your post. Until the alternator can top up the battery to a semi respectable level. I'm assuming it's way worse on a cold morning? Think of it like the difference in battery life on your phone compared to when you got it, to the end of your contract. Then think of it over 12 years.

It sounds the car has been poorly maintained, i'm amazed it hasn't died on you yet. It is imperative you change the oil and oil filter ASAP.

 

[Blue in Munich]

My thoughts, for what they are worth, would be to look at the head gasket or cylinder head. When cold, the failed head or gasket will allow coolant past which then results in poor running as the mixture isn't right and the white smoke as the coolant is burnt off. As the car warms up & the metal expands, the crack can then seal up, resulting in normal running & normal exhaust colour. Turn it off, it gets cold, the leak reappears & the whole cycle starts again.

Is the coolant level dropping? Also remove the oil filler cap; is there a light brown "mayonnaise" there on the underside? If so, that's your problem.

I don't buy the battery; once it's turned the car over the alternator should kick in & give a decent level of electrical power. If it hasn't been reluctant to start before this I doubt that the battery is your problem. Damp in the electrics could make it reluctant to start but I don't think would explain the white smoke.

Good luck.

 

[DanFST]

My thoughts, for what they are worth, would be to look at the head gasket or cylinder head. When cold, the failed head or gasket will allow coolant past which then results in poor running as the mixture isn't right and the white smoke as the coolant is burnt off. As the car warms up & the metal expands, the crack can then seal up, resulting in normal running & normal exhaust colour. Turn it off, it gets cold, the leak reappears & the whole cycle starts again.

Is the coolant level dropping? Also remove the oil filler cap; is there a light brown "mayonnaise" there on the underside? If so, that's your problem.

I don't buy the battery; once it's turned the car over the alternator should kick in & give a decent level of electrical power. If it hasn't been reluctant to start before this I doubt that the battery is your problem. Damp in the electrics could make it reluctant to start but I don't think would explain the white smoke.

Good luck.

What is your experience with cars? as that is a very far fetched and scaremongering post.

 

[GreiginFife]

If the charge in the battery drops to 9.5-10v this would cause stuggle starts, the engine components that run off of the battery don't suddenly switch to a separate circuit when the alternator "kicks in" and still run off of the battery which will pick up more charge as the alternator feeds it (assuming the alternator is 100% efficient).
This can be demonstrated as lumpy although its really just mord of a limp mode.

Personally, if it was my motor I would be testing the battery charge when idle and then tracking its charge once started. Most likely idle is about 10v and once running on alternator takes that minute or two to get up to the 14.5/15v mark.
My 2002 Astra suffers the same problem if its sat for a while (different cause of the same symptom) starts up like a bag of spanners before coming good. Battery test showed idle 10.1v rising to 15.8v after approx 2mins.

Talk of head gasket, while not unrealistic, is maybe a bit drastic.

IMO with how ignition systems are set up on more modern engines (mainly sealed units) spraying WD40 on snything won't help. I would also be skepticsl of condensation build up each and every time.

All just my opinion though, I did 3 years of my apprenticeship but that was a long time ago (1996) and these days I only do project cars stripping and rebuilding engines and running gear.

Just an additional thought to add: white smoke will be a result of any imbalanced fuel/air mix on a poor start up from every experience I have of it. It will also give a petrol smell if a little rich a mixture.

 

[DanFST]

If the charge in the battery drops to 9.5-10v this would cause stuggle starts, the engine components that run off of the battery don't suddenly switch to a separate circuit when the alternator "kicks in" and still run off of the battery which will pick up more charge as the alternator feeds it (assuming the alternator is 100% efficient).
This can be demonstrated as lumpy although its really just mord of a limp mode.

Personally, if it was my motor I would be testing the battery charge when idle and then tracking its charge once started. Most likely idle is about 10v and once running on alternator takes that minute or two to get up to the 14.5/15v mark.
My 2002 Astra suffers the same problem if its sat for a while (different cause of the same symptom) starts up like a bag of spanners before coming good. Battery test showed idle 10.1v rising to 15.8v after approx 2mins.

Talk of head gasket, while not unrealistic, is maybe a bit drastic.

IMO with how ignition systems are set up on more modern engines (mainly sealed units) spraying WD40 on snything won't help. I would also be skepticsl of condensation build up each and every time.

All just my opinion though, I did 3 years of my apprenticeship but that was a long time ago (1996) and these days I only do project cars stripping and rebuilding engines and running gear.

Just an additional thought to add: white smoke will be a result of any imbalanced fuel/air mix on a poor start up from every experience I have of it. It will also give a petrol smell if a little rich a mixture.

Spot on, I'm also willing to bet the "White Smoke" Is just condensation.