My A4 avant 1.9tdi B5 Judders violently when I accelerate hard

[WillSilv]

Hi everyone,

Iv just bought a W reg A4 avant 1.9tdi, I must say the car is great, however i have had an issue with the car juddering when I put my foot down hard enough. If i accelerate gradually there is no problem at all, it revs beautifully and can get to a decent speed. When I, for example, accelerate hard out of a roundabout in a lower gear it can judder violently, this stops as soon as i lay off the throttle slightly but it returns whenever I quickly put my foot hard down on the accelerator. Iv also noticed a rough/ lumpy tick over that is intermittent. Iv bought a new fuel filter and a diesel system cleaner that I will use in the coming days.

Just wondering if any of you lot might know cause of this issue?    

many Thanks!!

[Dan3222]

I think you have already hit the nail on the head mate, fuel filter. Change that first and see how you get on with that. If it is a blocked fuel filter, it starves the engine of fuel under more rapid acceleration, causing a judder. Injector cleaner is always a good thing to use too.

welcome to the forum mate too.

[WillSilv]

Cheers, and thanks for the reply. As you say it sounds a lot like fuel starvation, I'll smack that new filter in and see how I go from there

[Rustybear]

Hiya mate, did the fuel filter solve the problem? I used to have a pd130 bora, mine never had this problem, but a lot of guys and gals had the problem of the turbo vanes sticking open/close. Guessing yours has a vnt turbo? This usually causes a juddering, but then usually limp mode...hopefully the fuel filter sorts it though

[jbh110tdi]

what bhp is it? do you know if its the VE or PD engine? 

[WillSilv]

The fuel filter did not solve the problem unfortunately, i tested the MAF sensor by unplugging it and going on a short drive, the car drove fine with no juddering, so i bought a new MAF and installed it, took it out and the problem persisted even with the new MAF! Iv just posted another thread about my car which is now more urgent, iv has terrible luck with it. I think there is something horribly wrong with my electronics somewhere 

also it's a 110bhp VE

Thanks for the replies

[jbh110tdi]

I had this problem with the 110 VE AFN as well. if you check the loom going to the MAF and pay close attention to where the wires go into the plug. even give them a wiggle and see if any break off. check the loom closely as you go up it there may be a break in the cable. My old silver FWD had a split in the cable which gave this problem. my old green Quattro where the wire went into the plug it had more or less fell to bits through age. I got a replacement plug and some wires from the dealer and soldered it in. 

[JonAudiFriendSmythe]

Front snub mount, i had the same issue, the font engine snub mount had failed and was moving around upon acceleration, it's a simply but lengthy job, you'll need to partially remove the from of the car, lights out etc, same aws you would for a cam belt change, then right at the front in a rubber with a cup, replace the rubber, fixed mine no problems.

 

 

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