xsrfsno225x

ok so a friend on mine suggested that i dont buy a 2000 1.8t A4 with 78k miles. A mechanic told him that the problems with my friends vr6 gti stemmed from a bad coil, causing unburned fuel to the catalytic converter and killing the supplemental air pump....

usual problem for a 2000 1.8t a4?? anyone know of anything similar??

the car also has a check engine light on. I drove it and everything runs perfect, no idle surge or miss or even a little choppy. The dealer said that he would take care of whatever is causing the light. (I know that if he pulls out the bulb it wont lit when the key is in the on position.)

Someone please offer their opinions

RAUDI S6

I have a 2001, and my secondary air pump keep's throwing a CEL, I just reset it evry 3 oe 4 months when it comes on. The car runs fine, and I am in So Cal where it does not get too cold to need it. I am not sure if I am doing long term damage or not, but for a year now, it has been fine.

xsrfsno225x

This pump supplies air to the cat for cleaner emissions? I dont know. I don't want to get myselft into a headache of a car...with any other problems

ChooChooNongNongHead

It's a simple cheap fix if that's the case. I know that the 2.8 hoses have some pretty good bends in them and that type of hose wears out.
I was replacing my combi valves ( i thought they were the cause) when I noticed that the hose going to one was completely spit. I fixed it and hadn't had a code in 6 months.
Like you I was resetting the CEL every two days.

xsrfsno225x: Chances are the will NOT remove any bulbs for that CEL. If they are a bit shady, all they have to do is reset it and it probably will not reappear for days. All you have to do is take it for a drive and have a mechanic hook it up and check the readiness to see if it passes or fails. Someone can also scan it for "hidden" codes. (codes that are there but just havn't triggered the warning light yet) I believe that it will need multiple starts / miles driven to pass the readiness test after a reset so even if they do fix the issue, you may not get a pass.
I usually got mine to pass after a few short trips after a CEL reset.
Search around, chances are that the secondary air pump is okay but a hose or valve may be the culprit. There are many diagrams and threads on this subject.

Keyword's to use when searching:
SAP
secondary air pump
combi valve
kombi valve
incorrect flow

ChooChooNongNongHead

is the issue that caused the CEL on the car you are interested in.
You got to look around here a bit.
The Audi is NO honda. They need a lot of attention and have a few issues from time to time. If you are looking for a car that you put gas / oil in and drive... look at different brand.
This place is a gold mine of knowledge so if you are okay with tools & you don't mind getting your hands dirty from time to time, you've come to the right place. If this is not you, expect to pay tons at the dealer for every little issue that pops up. The A4 can be a fun car or a nightmare... it's all up to you.

you should verify that the T-belt has been done on the car. If you buy it and don't know if it was or not, expect to pay a good buck +/- $800-1K for this job... unless you do it yourself. If neglected, you'll have a pile of useless crap sitting in your driveway.

xsrfsno225x

Suppose that the Timing belt was not replaced... How big of a job is it on a 1.8t?? Engine need to come off the mounts or just the head off?

ChooChooNongNongHead

as it seems) The A4s are suppose to go into "service position" which means the bumper cover comes off and some bolts are removed to bring the front end out a little bit to work on it. When doing the t-belt, you'll just have to go one step further and remove the entire thing. There is a step-by-step procedure for doing the t-belt in the tech section. You'll also want to do a few other things since the nose is off and you're digging in there anyway.
T-belt
water pump
t-stat
rollers
tensioners (not sure if this applies to the 4cyl, I have a 2.8)
These things can be purchased as a "kit" you'll have to ask where the best place to get the stuff is later.
You should also consider getting a new snub mount, (hockey puck mount between the radiator support and frame) You'll also need coolant (G-12) and check the condition of the other belts etc. Again, this stuff won't be any extra labor since you're in there.
Check out the tech section to get a better idea.
It's not a hard job... everything is right there once you get the nose off. You shouldn't need any audi specific tools for the 4cyl (2.8s need a tool to line up the cams)

Tech section and the FAQ section should have many answers for your questions.