I have a 99 1.8t AEB A4 automatic. It's had a hard start up problem since I bought it but idles good after I drive it a little. It never had a CEL on. It came on the other day and I scanned it and it read P1250 Fuel level too low, and P1565 Throttle position lower limit not attained. I figure it was a bad throttle body. So my first question is does it matter if I replace mine with a throttle body from a 99 manual transmission 1.8t? My next question is I believe my car went into limp mode. I started to drive it today and the transmission would shift extremely hard and in 1st and 2nd gear it would free rev if I tried to give it more than 25% throttle. I also cannot rev past 4000 rpms. Do you think this is just b/c the car is in limp mode and do you think these codes would cause the car to go in limp mode?

 

Sounds like your tranny is now slipping. I'd scan it again and see if you get any codes for your transmission (TCM/TCU)

 

as for the throttle body, it should not matter in the slightest if its a manual or auto tranny since these are in no way connected electronically. (correct me if I am wrong). +1 on rescanning the car and double check the fluid levels. My chevelle was really jerky and stiff right before the tranny fried but never fluctuations in the revs...

 

I will scan it again. I don't think the tranny is the problem b/c 1) Tranny was just replaced about 5000 miles ago. 2) It shifted perfect through every gear just hours before this started happening. And as for the TB I'm talking about replacing it with the sensors and everything from a manual 1.8t.

 

Why? Have you done a throttle body adaptation? If not, search for it. Have you played with all the sensors? (double checking connectivity) Its the small things first.

 

Yes I have checked all the sensors and I was going to replace it b/c I was getting those 2 codes which from my research led me to believe it was one of the sensors on the throttle body. I can find a used one for cheap that's why I am buying a new one.

 

Scanned codes again and still getting the same 2. P1250 and P1565. Cleared the codes and the transmission shifts normally now. Problem is my car still doesn't want to go past 4000 rpms. I think my coolant sensor is bad because my gauge never goes above the second dash from the left. The one to replace is the 4 prong one that is on the back of the motor on the coolant pipe correct? Would a bad CTS cause the car to not rev past 4000 rpms?

 

absolutely not. Mine sensor is as dead as a door nail, i can get waaay over 4k. Not that I like to, or recommend it.

Your 4k thing is puzzling tho...

 

Ya I didn't think that would cause it. My guess is leading me to believe I might have a bad MAF. Is it possible on the 1.8t's to have a bad MAF with no CEL lights? Well I still might have the 2 codes I cleared but they haven't come back on yet. I already cleaned the MAF with MAF cleaner just so you know so nobody recommends doing that.