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Jerry, Master Mechanic
Category: Audi
Satisfied Customers: 17218
Experience:  ASE Master, 30+ years exp. imports and domestic, former shop owner
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My 2004 A4 is "surging" or jerking when accelerating,

Customer Question

My 2004 A4 is "surging" or jerking when accelerating, especially up hill.
JA: Tell me a bit more about what's going on so he can help you best.
Customer: I can tell it isn't the transmission. seems to be a fuel system problem
JA: Are you hoping to fix this yourself?
Customer: If possible
JA: Is there anything else the Audi Mechanic should be aware of about your Audi?
Customer: Not that I know of. This just started a day or two ago
JA: I'm sending you to a secure page on JustAnswer so you can place the $5 fully refundable deposit now. While you're filling out that form, I'll tell the Audi Mechanic about your situation and connect you two.
Submitted: 1 year ago.
Category: Audi
Expert:  Jerry replied 1 year ago.

Hello and thank you for using the site. My name is ***** ***** I will be happy to assist you today.


Let me just say that any money that you paid, or if you have a subscription, that money stays in your account until the answers are rated, (positive) regardless of how fast or how long it may take to get finished. You can FOLLOW UP AT ANYTIME, even after rating.



You will want to check the fuel pressure to see if it is too low. Also that the filter is not restricting the flow of fuel.


Then if the fuel pressure and flow are good, the exhaust may be a little bit restricted. You can have a back pressure test done on it at most exhaust shops to see if the cat is clogged.



If they are both ok, then you will want to take a sample of the fuel to be sure that it’s not contaminated.


Please don’t forget to rate the answer, **** THAT IS THE ONLY WAY I GET PAID **** if you need any more on it, I will be here.


Expert:  Jerry replied 1 year ago.

Did you get that?

Expert:  Jerry replied 1 year ago.

If you accept my additional service request for your email address, you can give me your email in a private info box and I'll send you the diagrams and pinouts in a PDF file, the file is rather large.

You will just have to accept the additional service offer and ENTER your email address in the “ENTER CONTACT INFO” section so that I can see it.

Customer: replied 1 year ago.
Is this testing something that an Autozone could do? My regular mechanic is closed for a few days. I know there's a casing over my engine that I don't have the tools to check.
Since this just started and seems to get worse going up a hill, in your opinion, do you think it could just be bad gasoline? And could a fuel system cleaner you add to the gas tank help at all?
Expert:  Jerry replied 1 year ago.

Normally we get paid for the original answer(s) before any follow ups, but I would highly doubt that Autozone could do that and the additives won't compensate for low fuel pressure or bad fuel, thanks

Customer: replied 1 year ago.
My car broke down shortly after getting your answer so once my mechanic tells me what is wrong I'll rate your answer based on accuracy. Thanks
Expert:  Jerry replied 1 year ago.

So sorry to hear that. It sounds like the fuel pump may have totally given up, (if the gas is good in it). Thanks and please let me know what you find out.