Engine jerk Passat B5 1.8T Year 2000

[tjompen1968]

Heeeelp... My engine jerks sometimes when holding a steady 70-80 km/h.
It feels like really short jerks like if the ignition fails for a very short time.
This happens from time to time. I have found that if I drive really careful this does not happen but if I drive more offensive and revs the engine the problem appears. I also feel that It lacks power or hesitates when I want to speed up fast.

I have checked all vacuum hoses, puck-valve etc etc. Cleaned the butterfly valve, checked the spark plugs, checked the tires, checked fault codes but there are none. I have tested the MAF, unplugged it, cleaned it, checked with VAG-COM. It looks ok.

I have searched all forums and been given ideas what to look for but I still come up dry.

Now I look to you for help.

/Tjompen


It is with Manual Gearbox...

[martin1810]

Faulty coil pack or spark plug ? especially if it happens more when warm.

[tjompen1968]

Wouldnt this give any kind of fault code?

I have looked at the spark plugs and they look like they are doing there job. Will check again.

More ideas please so that I can try a lot of things when lifting the hood this weekend.

Thanks for the reply

[tjompen1968]

How do I check the coil packs?

[tjompen1968]

Well, today I am a happy man

The jerking is gone...knock on wood...

After 6 months! of fault finding I reluctantly went and bought a new G62 temp sensor. I also bought a thermostat, just in case. Did NOT belive it could be the sensor.

I made measurements on the new and the old sensor and found no difference between them, not broken? Hell, this was the last solution...

Drove the car with VAGCOM and found that the engine temp did not pass 78 deg C. Hm? Why only 78, should be at least 80, 90 would be perfect but 78. New sensor the same.

The car has had bad milage and have been weak.

Removed the old thermostat and boild some water. The old and the new opened and closed at the same temp more or less. No difference. ****.

Well, I did not reuse the old thermostat and nore the old sensor. With the new thermostat the car suddenly felt stronger, VAGCOM showed me 93 deg C!

If this had been an 1988 I would have found this problem first day but all this hi tech stuff made me look for the difficult solution.

It was the bloody THERMOSTAT! Somehow it had changed its 87 deg C for 75 deg C. I guess it was just old and tired...

6 months!!!