Bought '98 Audi A4 1.8tq w/125,000 miles from local guy at the end of February. Looks pretty stock but has most of the bolt on stuff done, i.e. K&N filter, chip, larger turbo, exhaust, coil-overs, etc. Seemed really solid at first but since purchase have had the following problems:

Fist time I filled up the car with gas it did not want to start. Got it started, although CEL came on, and talked to previous owner who had similar problem in the past. Suggested that I either clean or replace the Evap Purge Control Valve. Did that and was back in business, CEL went away and have not had fill-up/hard start problems.

About a month later drove the car to Point A, parked it for about 4 or 5 hours (I live in AZ, it was hot) and when I came back out and started the car the idle was immediately super rough. Limped it home (about a mile), eventually got flashing CEL. Searched forums (thanks audiforums.com!) and figured it was plugs/coils. Bought and replaced plugs/coils, still had rough idle problem. Took to local shop, scanned and told me it was the Ignition Module (quoted me almost a grand to do module/coil). Bought and replaced Ignition Module, back in business, CEL went away...for the moment.

Last week, CEL comes back on. Didn't notice any performance issues first day, but after a day or two it started sputtering (missing?) when I would get into the boost. The sputtering got worse under boost and the CEL would flash and then go solid again when I got out of the boost. Went to a friends house who had offered generic scan tool and on the way home as I pulled into my cul-de-sac the engine died. It just died and I rolled into the driveway. Now it cranks and all the electric stuff will come on, but it won't turn over at all. Generic scan tool gives me two codes, P0301 and P0327. Tried changing spark plug and coil on cylinder 1 which didn't help. I can hear the fuel pump trying but it doesn't seem like the engine is getting any gas. Ordered a fuel filter, which should be here in the next day or two. I am going to try that. In the mean time, when I tried to start it after switching the plug and coil, I got a flashing oil pressure light.

Sorry for the super long post, I just wanted to lay it all out there. Thanks in advance for any ideas anyone has. I love the car and I don't mind working on it. I realize it is 8 years old and has 125k+ miles on it and that I am going to have to fix stuff as it wears out/breaks/whatever, I just wanted to try to figure out what was wrong so I don't get hosed at a shop. I have the previous owners' Ross-Tech software but I can't get a new activation code because I'm not the one who bought it so I will probably have to buy that stuff new. Anyway, if anyone has any ideas I would certainly appreciate them.

 

I,

The first thing, do not change the fuel filter, you spend money for nothing! The basic things to check is:
cylinder compression ---> (broken timing belt), fuses, gas delivery and ingnition fire when cranking....

 

Thanks to everyone who took a look at my super long post. I wanted to update it and I have new (sort of) issues so I figured I would see if anyone had any ideas with this new information that has come to light.

OK, switched out the Ignition Module back to the old (original?) one that was on the car when I bought it. I just thought I would see what would happen. Car started right up but the idle was rough, so it was obvious that the Ignition Module had gone bad again. Looked around and found Ignition Modules for a great price at AutohausAZ and the info there suggested replacing all Spark Plug Connectors at the same time as doing Module. Did all four Ignition Coils (Plug Connectors attached), new plugs, new Ignition Module, oil change, didn't do the fuel filter (thanks AudiTEK!) and the car started right up and is running better than when I bought it. Pulls hard and strong under boost, idles great, seems great.

A few days later, CEL comes back. Generic scan tool gives me 5 codes now, P0300, P0301, P0302, P0327 and P0134. I'm bummed but the car is still running great. The P0134 is a pre-cat O2 sensor code so I am thinking I am going to go ahead and do that.

Can anyone think of anything else that might be causing these failures. The car feels like it running hot but the temp gauge never gets above center. I have thought about doing the thermostat just to get it out of the way, but I really want to figure out what the root problem is that is causing all this stuff. It just seems like it is something else and these are just symptoms of a large (or different) problem.

Thanks again, I know I have rambled like crazy so...thanks again!