Heres the car. 93 t/a a4

Heres the problem:

Excessive gas consumption, massive loss of power. Does not really pick up untill 3k rpms and even then its still not right. Took me a half mile to get up to 90 shifting at 5k every gear. I have replaced the entire ignition system, fuel filter, pcv, battery. Checked FPR and all sensors. (I may be forgetting something there). I have no trouble starting. This has been going on for months and I am really sick of it. Had the shop check over everthing and they had no idea, then i began troubleshooting myself. I had them check the fuel pressure and they said it was fine. The only difference since i had them check everything was, i hear the fuel pump alot more than i did before. That is my last guess for what it could be. Im desperate.

 

Did you check out the fuel pump relay?

 

no, i havent checked that. where is it located?

 

Have you looked at the O2's? I think excessive gas consumption and lack of power could be O2's.

 

thats one thing i forgot to mention. I just replaced those.

 

The fuel pump relay is either going to turn the pump on or not. If you want to check something to do with fuel, check the pressure. You could also have a problem with the MAP sensor. It could easily cause low power and poor gas mileage if it was acting up. It would be best to get a scan tool on it to see if it was looking funny.
You can read about expected readings here.

 

what mods have you done?

How is it at idle?

Have you modified anything to the intake elbow?







jason

 

this is a long shot but could it be something like a break sticking. i had a caliper stick on my truck and it slowed me down so much. it took forever to get to speed and when i did i was reving way faster thn i should have been

 

only mod is a new muffler.
the idle is a little high, hovers around 900 to 1000.
i have not changed anything on the elbow

 

i thought of that too but the low end power is what i have the most of. anything over 2k, it is a dog. i think that would eliminate a sticking brake.

 

i would assume if it doesnt throw any codes than this is working properly. no codes being thrown.

 

ok, i ask because my car displayed similar symptoms. I had gotten rid of the long plastic thingy on the intake elbow, plugged the hole with a ghetto fix. Ran fine for a VERY long time, til one day it ran just as you described. Turns out that my cheap ghetto fix had fallen out an left that hole exposed on the elbow. Hence my car ran like crap, plugged it back up VERY good this time and all was back to normal

I would just inspect the intake elbow to rule out any possibilities





jason

 

there have been many times where i would liked to remove that thing, but i havent touched it. ill check the elbow again but im sure that everything is ok.

 

I had a relay go out on my truck about 40 miles from home. I had bucking at idle, WOT was fine, but during normal driving it would buck and then go, etc. etc... I also was getting poor mileage as well... so I made a toggle switch and direct line from the battery to power the inline pump until I could get into town to get a relay... ended up replacing the pump too.

Oh yeah, and fuel pressure was fine too... even with a pump on the way out, or a bad relay you can have normal fuel pressure, unless you check it while the car is running for some time you will see the drops in pressure, but since the whole system is pressurized upon startup and after its shut off, you can't really get an accurate reading (for that type of problem) without driving the vehicle with a gauge. That's what finally caused my relay to **** itself was a small bump in the road.

 

catalytic convertor?