Hello all,

i bought my 2002 cvt jazz in 2006, spend with it 30k kms without any serious problem. Now it has 70k kms. It always had some feeling that the engine misfires some times, but it was very rare and only felt as a very small bump. This time it really gets from bad to worse.

If i start with only a few mm-s on the gas its starting to twitching as long as i put my leg harder on the pedal. I dont want to use the gas digitally, on/off.

Ignition coilpacks checked/swapped, spark plugs changed, no CEL, fuel economy down( ~6.2 -> 7.2 l/100km ). Is there any suggestion, where to continue the search? Visited my dealer, they told me it has to be the CVT, lets change the ATF, but it did not help. The computer tells nothing even until the car shows the problem.

Thanks for everybody in advance!
cheers,

gram
anyway, a satisfied owner

 

possibility that this is just bad gas?
1.) is this the only tank it has done it?
2.) Is your car burning coolant?
3.) Does this happen just when its cold? Or even after its been running for over an hour?

 

Thanks for your response.
1; it was always an issue, on the 30k km i drove, but recently it got more serious.
2; No, everything is fine except the nasty twitching at mild acceleration. On highway, or under half-heavy load its fine.
3; After starting, on the first 1-2 km the problem doesn't exist, just when the engine got the operating temperature.

Thanks again!
Cheers,
gram

 

How long since the last fuel filter change?

 

I think its original, as the maintanance schedule writes it should be reaplaced at 120k kms. I didnt think about it, thanks for the idea. But why the problem showes only with operating temperature engine and mild load?

Thanks, cheers,
gram

 

[quote=gram;384559]Hello all,

i bought my 2002 cvt jazz in 2006, spend with it 30k kms without any serious problem. Now it has 70k kms. It always had some feeling that the engine misfires some times, but it was very rare and only felt as a very small bump. This time it really gets from bad to worse.

If i start with only a few mm-s on the gas its starting to twitching as long as i put my leg harder on the pedal. I dont want to use the gas digitally, on/off.

Ignition coilpacks checked/swapped, spark plugs changed, no CEL, fuel economy down( ~6.2 -> 7.2 l/100km ). Is there any suggestion, where to continue the search? Visited my dealer, they told me it has to be the CVT, lets change the ATF, but it did not help. The computer tells nothing even until the car shows the problem.

At this distance without laying hands on we'll stay with the simple stuff.
I'd check the throttle valve positioner and the throttle driver. It might help to run a couple of cans of fuel injector cleaner thru according to directions. If you can use one without alcohol.
And when you replaced the spark plugs did you get a reading on the plugs? (was one pretty sooty?)
And have you adjusted the valve clearances?

 

No guarantee, this is it but debris in the filter could settle when the car isn't running and it takes a little time for the debris to recirculate when starting up. The right kind of sloshing causes the problem to occur, more acceleration could clear the debris again. Water in the filter can could do the same thing - I had a similar problem with an old saab that cleared up once I ran some dry gas through it. Bad gas could cause these kinds of problems well before the mileage recommended for change.

The way I look at it, dry gas and fuel filter are easy potential fixes that are worth the time and cost in these situations because they are cheap and fix some fairly common issues in cars.

 

The next round of things I would check are the sensors (TPS, MAF etc.), especially connectors. Unplug and replug the sensor plugs and wires. Check for corrosion while they're unplugged.

I had an old Fiero that did this because the internal connections in the TPS weren't soldered, just a copper electrode resting on a pad. Over time, the pad became corroded cause an intermittent signal from the TPS.

 

hi Gram, any news about this ?

i'm getting the same troubles these days, and i suspect the EGR valve needs to be cleaned/replaced...

 

Spark plugs ever been changed? New plugs & wires are probably due at 70K. Try feeding in some injector cleaner as well, doesn't hurt.

 

Thanks for all the attention, the problem was with the EGR valve. Now everything is fine, works like a charm.

regards,
gram

 

Glad it got fixed but DAMMIT, I got the diagnosis wrong.

 

Maybe i didn't tell you enough information.

 

EGR valve? that's it? Sweet!!! .. I've actually been having this exact problem for about 2 months now and did what you did; swap the coils around and swapped out the plugs twice and I even went through a whole Lucas fuel treatment bottle. I really hope this is the cure for my problem. if not, I'll go ahead and check/change the fuel filter.

Thanks again!

*edit* one question: did you have to replace the EGR valve? ....or just re-adjust it? or.. what?

 

A friend of mine helped to get around of problem. I though it has to be the EGR, but didn't have experince to handle it. We decided trying to clean it in firtst round. There was only a thin layer of carbon on the surface of EGR valve, cleaned, and works.

It was a nice sunday, so couldn't get a new valve, but maybe it's really enough to clean it. It was a few weeks ago, the comsumption went back to 6 l/100km within the city, no more twitching. Go ahead.

 

DOPE!

I'm really hoping this is worka for me.

thanks again.