Passat B5.5 Jerking

fear corcaigh

My 03 130 bhp Passat is shuddering and jerking when I am accelerating hard. I have given the car to a few people with varying responses. It also seems to be using excessive coolant, I'm putting roughly a litre in every 2 to 3 weeks.

One guy said it was the flywheel so I changed to a single mass flywheel but it didn't stop. Another says it could be the gearbox but I have my doubts.

I have disconnected the airflow meter and found that the performance of the car was much worse so I don't think it is that.

Anybody got any idea what it maybe

juannjo

Hi,
I have a 100 bhp 03 TDI passat and am expierencing similiar jerking on motorway at 70-80mph, especially going uphill.

Just wondering if got to the bottom of this.

keithclancy

fear corcaigh wrote: »

My 03 130 bhp Passat is shuddering and jerking when I am accelerating hard. I have given the car to a few people with varying responses. It also seems to be using excessive coolant, I'm putting roughly a litre in every 2 to 3 weeks.

One guy said it was the flywheel so I changed to a single mass flywheel but it didn't stop. Another says it could be the gearbox but I have my doubts.

I have disconnected the airflow meter and found that the performance of the car was much worse so I don't think it is that.

Anybody got any idea what it maybe

It shouldn't be using any coolant .. means theres a leak somewhere.

Check the oil .. does it look like mayonnaise ?

vw_driver

fear corcaigh wrote: »

My 03 130 bhp Passat is shuddering and jerking when I am accelerating hard. I have given the car to a few people with varying responses. It also seems to be using excessive coolant, I'm putting roughly a litre in every 2 to 3 weeks.

One guy said it was the flywheel so I changed to a single mass flywheel but it didn't stop. Another says it could be the gearbox but I have my doubts.

I have disconnected the airflow meter and found that the performance of the car was much worse so I don't think it is that.

Anybody got any idea what it maybe

I had a similar issue with my car. It turned out to be a wiring loom for the injectors, which crack and cause the shuddering problem. It cost about 100euro to fix. Its a common problem in golfs, boras and passats of that vintage. Deffo worth looking at this as a possible solution

juannjo

Hi vw driver,

I had the same injector wiring problem months ago - initially a gradual shuddering problem under load that over a couple of weeks led to complete misfiring. The connection to injector#1 came loose was the root cause.

At the time, this was fixed by just remaking the connector. But maybe if the connector is loose again, I need to replace the entire wiring harness with a new one wiring loom.

Other idea is the clutch.

vw_driver

juannjo wrote: »

Hi vw driver,

I had the same injector wiring problem months ago - initially a gradual shuddering problem under load that over a couple of weeks led to complete misfiring. The connection to injector#1 came loose was the root cause.

At the time, this was fixed by just remaking the connector. But maybe if the connector is loose again, I need to replace the entire wiring harness with a new one wiring loom.

Other idea is the clutch.

A good independent mechanic should be able to see if the ecu is throwing up any errors etc. but mine didnt show ay errors.
Replacing the full wiring loom is best first option. Apparently the loom is kept in a bath of oil so eventually cracks and breaks after years.
Mine was intermittent, was jerky starting sometimes or on the motorway. I initially thought it was an injector problem caused by bad diesel but thankfully just the loom.

fear corcaigh

I haven't got to the root of the problem, the oil does not look like mayonnaise and the head is fine. I have plugged it in but no errors are coming up. I have changed clutch and flywheel but no improvement.

I think i will try the injector problem ye are talking about.

juannjo

For a misfire due to injector wiring connector, you should be able to read the following error code/message "8074 P1666 Unit injector solenoid valve, no. 1 cyl. -N240 Electrical fault in circuit". Due to its position/length of wiring, the connection to injector#1 is the cause.

crosshair1

Does It happen throughout the rev range?

fear corcaigh

2k to 3k revs, also its using a lot more fuel

corktina

i thought i was on after hours when i read the title

crosshair1

No fault codes and a hesitation in that rev range, I would be checking tandem pump pressure.

GSBellew

I had the same problem with hesitation when pushing hard and changing the tandem pump and the gasket between it and the cylinder head sorted it.

You would need to look at your coolant loss though.