Car jerks on gear change

[Louis]

So my car has vibratechnic engine/gearbox mounts and an evol mount ( all less than a year old) and black series bushes everywhere else. For as long as I can remember the car seems to 'jerk' between upward gear changes. I tried pulling the engine forward a while back and this did seem to improve things but it soon went back to how it was.

Do I have a deeper problem? Everything is torqued up and all mounts loctited. Bit fed up of it now, seems more noticeable when cold but still there regardless.

 

[imprezaworks]

Mine did this on the odd occasion, like it went into gear instantly, no give, if that makes sense?.

 

[Louis]

I need to record it really but probably hard to get on camera. It's really bad when cold recently but not first thing in a morning, only when driving home after work. Pops and bangs and holds back for about 400 metres then it's 'okay' again. Never used to pop and bang

 

[JamesBryan]

Fueling issue or your timing is out.

 

[Louis]

Fueling issue or your timing is out.

All belts changed less than 2 years ago at diamond motors. Never buzzed the engine so should be OK?

 

[imprezaworks]

What fuel do you use, has it changed

 

[Louis]

What fuel do you use, has it changed

Only shell but does it regardless of being 95 or 98 ron

 

[JamesBryan]

All belts changed less than 2 years ago at diamond motors. Never buzzed the engine so should be OK?

Yeah be fine then.

Do you let it idle for a minute or two before driving? Mine is quite rough if I drive it straight away.

 

[bloke]

blow on exhaust, lambda and i've just started seeing a few bad map sensors recently. can't remember when i saw one last but last few weeks had four or five.

 

[Louis]

Yeah be fine then.

Do you let it idle for a minute or two before driving? Mine is quite rough if I drive it straight away.

Yeah, it'll still jerk when warm but not as bad.

blow on exhaust, lambda and i've just started seeing a few bad map sensors recently. can't remember when i saw one last but last few weeks had four or five.

Literally just had all the exhaust done with a v-band and a crack welded up at the back so that's as sorted as its ever been!
Lambda, wouldn't I see an EML? I have none even with decat (Post lambda is tied above heatshield).
Interesting you mention map sensor, i had problems with a dodgy green o-ring but I changed it over. Pretty loose inside of the inlet though, think this might be my issue?

 

[JamesBryan]

Does it use lambda on cold start though? Thought it was open loop until it got warm.

 

[Louis]

I have a genuine lambda I can replace it with aswell as a spare map sensor. See where it gets me!

 

[STEVE.M]

So my car has vibratechnic engine/gearbox mounts and an evol mount ( all less than a year old) and black series bushes everywhere else. For as long as I can remember the car seems to 'jerk' between upward gear changes. I tried pulling the engine forward a while back and this did seem to improve things but it soon went back to how it was.

Do I have a deeper problem? Everything is torqued up and all mounts loctited. Bit fed up of it now, seems more noticeable when cold but still there regardless.

It depends what you mean by "jerk".

With a responsive normally aspirated 2.0L firmly mounted engine, I`d be disappointed if I could not feel a punch when you get back on the power.

As long as you cannot feel any movement in the gear lever on and off the throttle @5000 rpm in the 3rd gear, I doubt you have a problem regarding engine

mounts, drive shafts etc.

Pops & bangs, combined with erratic power delivery when cold would suggest it`s time to change the lambda sensors, they are only meant to last 90k miles.

Proper Bosch one`s can be bought for £37 a piece.

 

[Louis]

It depends what you mean by "jerk".

With a responsive normally aspirated 2.0L firmly mounted engine, I`d be disappointed if I could not feel a punch when you get back on the power.

As long as you cannot feel any movement in the gear lever on and off the throttle @5000 rpm in the 3rd gear, I doubt you have a problem regarding engine

mounts, drive shafts etc.

Pops & bangs, combined with erratic power delivery when cold would suggest it`s time to change the lambda sensors, they are only meant to last 90k miles.

Proper Bosch one`s can be bought for £37 a piece.

It's hard to explain, but maybe down to just everything being solid! It's when say I'm changing from 2nd to 3rd as the revs drop down when its in gear and releasing the clutch the car 'jerks'.

Only the pre-cat actually does anything on these am i right? I can change it easily enough. Cars on 133k now I think and i've never touched the pre-cat lambda.

 

[JamesBryan]

Change gear faster ?

 

[STEVE.M]

It's hard to explain, but maybe down to just everything being solid! It's when say I'm changing from 2nd to 3rd as the revs drop down when its in gear and releasing the clutch the car 'jerks'.

Only the pre-cat actually does anything on these am i right? I can change it easily enough. Cars on 133k now I think and i've never touched the pre-cat lambda.

I don`t think the rear lambda is there as a handy spare for when the front one fails.

Everything being solid will mean you feel it though.

 

[Louis]

Change gear faster ?

I wish that was my problem ?

 

[STEVE.M]

Change gear faster ?

The JC5 is a female box.

Only lets you slip it in when it`s good & ready.

 

[bloke]

lambda comes on pretty quick from cold start, can't remember exact temp though sorry.
if you can check what map sensor is doing.

 

[Louis]

How do I check that Carl? I have no fancy tools apart from a crappy plugin Bluetooth obd2!

Just been out in it again now and it isn't as bad as I was probably thinking but definitely something not 100%. I'll swap over the map sensor tomorrow as that's easy to do and maybe lambda if it's not wet...
Wouldn't a bad lambda give me eml or not if it's still kinda functional?
Soon end up throwing parts at these sorts of things! Thankfully I have some spares kicking around that I can chuck on. Nothing brand new though...

 

[STEVE.M]

How do I check that Carl? I have no fancy tools apart from a crappy plugin Bluetooth obd2!

Just been out in it again now and it isn't as bad as I was probably thinking but definitely something not 100%. I'll swap over the map sensor tomorrow as that's easy to do and maybe lambda if it's not wet...
Wouldn't a bad lambda give me eml or not if it's still kinda functional?
Soon end up throwing parts at these sorts of things! Thankfully I have some spares kicking around that I can chuck on. Nothing brand new though...

Just get on with it.

I replaced everything with new at 125k miles in August.

Injectors, coil pack, plugs, HT leads, Lambda`s, air & pollen filter, oil & filter.

Has run faultlessly since, and I am now on 133k, same as you.

Another oil change planned for this week.

 

[Louis]

Just get on with it.

I replaced everything with new at 125k miles in August.

Injectors, coil pack, plugs, HT leads, Lambda`s, air & pollen filter, oil & filter.

Has run faultlessly since, and I am now on 133k, same as you.

Another oil change planned for this week.

It gets all its oil and filters changed every 7k. Did the spark plugs about 14k miles ago but I might have a look at them see whether they're sooted up. Ktec filter was cleaned last weekend too!
Never a bad idea as preventative maintenance, they're old cars after all.

Cheers Steve

 

[STEVE.M]

It gets all its oil and filters changed every 7k. Did the spark plugs about 14k miles ago but I might have a look at them see whether they're sooted up. Ktec filter was cleaned last weekend too!
Never a bad idea as preventative maintenance, they're old cars after all.

Cheers Steve

Proper NGK plugs should be for 72K unless screwed by another issue.

 

[Louis]

Proper NGK plugs should be for 72K unless screwed by another issue.

They were from the carpartswarehouse on eBay in 2017 and sold as genuine plugs so doubt they're my issue

 

[Louis]

Swapped the map sensor, no change.

Got a video of the slight popping at idle, this just normal with a non res decat milltek system?



I'll change the lambda when it's not pissing it down! It's on and off which is really annoying

 

[JamesBryan]

Doesn't sound bad at all, probably smoother than mine ?

 

[Clio_fool]

Driver error I'd say. ?

 

[Louis]

Maybe I just drive bad when I'm cold and it's not the car ?

 

[bloke]

lambda can be almost dead and still not bring a light on. look at live data, see what your map sensor is reading with just ignition on and then when it's idling.

 

[Louis]

lambda can be almost dead and still not bring a light on. look at live data, see what your map sensor is reading with just ignition on and then when it's idling.

I'll have a look with my cheapo OBD then if it can do these things. I know it can do live data on lambdas.
What's 'normal' at idle/load with the map sensor? And similarly Lambda?

 

[Chris_Beer]

What I expected:

 

[Louis]

What I expected:

Haha, It does that when cold driving home from work but not sat idling! I'll try film that... Car feels like its holding back for the 400m.

 

[JamesBryan]

I'll have a look with my cheapo OBD then if it can do these things. I know it can do live data on lambdas.
What's 'normal' at idle/load with the map sensor? And similarly Lambda?

Lambda should flicker between 0.1 and 0.9 volts at idle.

 

[Louis]

Lambda should flicker between 0.1 and 0.9 volts at idle.

Alright, sounds good.
Wanted to sort this before going to EFI but doubt it'd be much of a problem for mapping?

 

[JamesBryan]

Alright, sounds good.
Wanted to sort this before going to EFI but doubt it'd be much of a problem for mapping?

Wouldn't want a dodgey precat lambda for mapping tbh, seeing as it controls the fueling and all.

That's if it is the lambda.

 

[Louis]

Wouldn't want a dodgey precat lambda for mapping tbh, seeing as it controls the fueling and all.

That's if it is the lambda.

Aye, i'll have a nosey tomorrow on my lunch. Cheers mate

 

[JamesBryan]

Aye, i'll have a nosey tomorrow on my lunch. Cheers mate

Might take a few minutes for it to start getting a reading, they need heat to work. That's why they have a heating element in them.

 

[bloke]

for lambda you really need to graph it and make sure it's switching evenly, no delays, sould give a nice even graph. let me know the figures you get from map sensor. it's very rare for them to fail but i've had three or four over last couple of weeks that have been out on ignition reading and that causes similar issues. had one that was lazy on a focus that was a right headache to work out the fault.

it can be mapped with an iffy lambda but you'll just need to sort it after mapping.

 

[Louis]

This is the lambda sensor, seems to be switching OK? I presume this is the first pre-cat sensor? It does drop below 0.1 on occasion.

How do i graph the map sensor? Couldn't see it on Torque but wasn't sure what to look for...

 

[JamesBryan]

Voltage wise it looks fine yeah.

I'm not actually sure how fast it should be alternating though, seconds or milliseconds.