blo94s4

i am still having hesitation issues. i did the efi coil upgrade, new plugs checked injetors, 02 sensor, new exhaust(stromung no cats) and vaLVE COVER GASKET. the car is chipped not sure which one but it was done at an audi dealership the previous owner worked for. runs between 18 and 20 psi at wot. i ran the codes and got a code for the maf. checked the maf and all the plugs for it were fine and i cleaned them up. i pulled the fuse on the ecu to reset it and the car runs worse but now i get code 4444 which i believe that means that the ecu is clear. the hesitation is bad at low rpms and is terrible between 3500 to 4500 rpms. i havent checked the fuelpump yet because it was done 40,000 miles ago by the previous owner and i am unsure how to test for that. i did a compression test and cylinder 1 and 2 were both at 175. cylinder 3 was 145. cylinder 4 was 170 and 5 was 172. does such a steep drop in 3 mean that there might be issues with that cylinder or is that normal? the car starts hard, cranks over alot and i have to press on the throttle to get it to start but sometimes it fires right up. cold running and idle was terrible before i did the 02 sensor but it still stumbles when cold. also the coolant seems to pouring into the resevoir not really bubbling but flowing very fast and constant when hot.. is that a head gasket or a stuck termostat? the thermostat and water pump were replaced with the timing belt about 25000 miles ago. ihave an appointment at a local shop in two weeks to try to figure it out but i would rather do it my self to save the money. any input would be great cause i am at my wits end. thanks

UrS4boy

You need to spend some time in the FAQ. (Switch to threaded mode first). There is a missing and hesitation diagonostic there plus comments on the compression test (your delta is quite big but probably acceptable).

audidrvr

Compression looks fine. Have you checked the air temp sensor and throttle position sensor? Both of those can cause that type of behavior if i'm not mistaken. If you need another MAF to try I could try and make some time to pull mine off (I have been meaning to do this for a while since it is just in there not even plugged in anymore) before i go on vacation.

blo94s4

i was in the faq's and thats where i got the info to do what i have done so far. wouldnt those sensors throw codes on the ecu if they were not functioning properly.

audidrvr

not necessarily. I believe you can put an multi meter on them to check their signals. I remember doing this for my TPS sometime ago and it turned out to be fine. I got the info on checking them from the FAQ.