looking at a 98 jetta, its throwing these codes, what do they mean?

Im looking a 1998 tdi jetta, that the guys says occasionally feels like it has no power and the check engine light come on. but it only does it for a day or two and then is fine for a while... here are the codes, im just not sure what they mean. Any insight would be great.
P1248
Injection Start Control Deviation
Start Of Cold Start Injector Control Difference

P1550
malfunction control vehicle speed idle speed contol auxiliary inputs[FONT=Arial, Helvetica, sans-serif]


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The first one means that the ECU is requesting timing advance and not getting it. It does this based on controlling the amount of injection pump case pressure pushing on a piston inside the IP. If there is no case pressure for whatever reason (case pressure relief valve innards ejected, clogged fuel system-- especially the filter, etc) then the ECU can direct all the (lack of) pressure it wants at this piston; it'll never be enough to advance the timing. I can show you a cool little ghost town in the middle of the desert in Arizona where you can swap a fuel filter when you get a light from this.

The second one would require a bit of googling and/or a guru, but it sounds to me like something that having a confused injector #3 would cause. The two together make me speculate (in a very much unsubstantiated way) that there might be some dirty wiring somewhere, possibly a Relay 109 or something.

well with that i think the car is not worth it, as it has 257,xxx miles, and also has no reverse in the 5speed tranny. And hes currently asking 1950, but i think i can get him down a good bit, but I dont want to deal with wiring issues.

The only wiring issues I would walk away from are those that have been hacked. The 'dirty wiring' that twentyeight mentions is usually the main engine ground, and the chassis grounds near the battery.

The IP 'MAY' need to be replaced. But you won't know until you get your hands on it. I would use that as a bargaining chip to drop the price at least another $500, maybe $1k!

I would recommend a timing belt replacement anyway, so the pump will be easy to remove at that point, if you find it's necessary.

$1k or so would get you a fresh rebuilt trans. Add ~$350 for a performance clutch that will handle nozzles and a tune.

Other than that, how does the car look?

Tony

The car looks decent, he says the timing belt was changed 10000 miles ago, but i never trust that the rollers were changed. Heres the pics and the craigslist ad....
http://smg.photobucket.com/albums/v491/cooguyfish/Stuff%20for%20sale/?action=view&current=PIC-0931.jpg
http://smg.photobucket.com/albums/v491/cooguyfish/Stuff%20for%20sale/?action=view&current=PIC-0932.jpg
http://smg.photobucket.com/albums/v491/cooguyfish/Stuff%20for%20sale/?action=view&current=PIC-0933.jpg
http://smg.photobucket.com/albums/v491/cooguyfish/Stuff%20for%20sale/?action=view&current=PIC-0934.jpg
http://smg.photobucket.com/albums/v491/cooguyfish/Stuff%20for%20sale/?action=view&current=PIC-0935.jpg
98 Jetta TDI, I have been daily driving this car for about a year and put around 10K miles on it. The car has 257,xxx miles.

we will start with the bad;
No reverse, I bought it this way and have been driving it around with out it for the entire time no problem. But you definitely can't back up in gear.
It's a little beat up, I won't lie it's one of the nicer cars I have owned, and I like it a lot, but I'm a little tight on money presently so I will be down grading If I can sell this.
so rust
tires are fairly worn.
and lastly, very recently it has developed sensor problem. Sometimes it runs perfect and sometimes it looses boost while you're driving. I haven't had time to look into it since it's very intermittent.
O, I'm pretty sure that it needs a thermostat, it takes a while for it to warm up when it's cold, I have one, just haven't had a chance to do it yet.

The good
newer alternator
newer timing belt (I'll have to look at the mileage when I did it, but It was around 10K miles to go)
also, all the tools for the timing belt will come with it.

If you have any questions, just let me know

Thanks

-Brandon

I have cleared the P1248 code on multiple TDis by simply replacing the fuel filter. Can't tell you much about the other code, though.