Posted: Fri May 26, 2006 10:01 pm
1) Its a VW, make SURE your prepump is running and working. Its maybe a fifty dollar pump. My Pops didn't replace his when I told him it was bad, took out the whole fuel system, headgasket, injector inserts.... It did a LOT of damage because he was running lean.
2) Check the voltage at the main pump. I FREQUENTLY see bad fuseboxes and grounds causing the pumps to get lower voltages. If it looks good at idle, its also easy to hook this up so you can watch it while moving. I do this test with test number 4. If you see the pump voltage drop as you load the car up, rerun your power and grounds.
3) I will repeat what was said above in another responese, DO A VOLUME TEST. You might even find that the billet filter is your issue...
4) FInally, do a fuel pressure test under LOAD. Not reving it in the driveway cause thats crap and not going to load the engine. Get it out on the road. You can usally duct-tape the tester gauge to the windsheild so you can see it while driving. Somebody else driving is smarter though.
If you do these four things, you WILL determine if the problem is fuel flow related or not. These are usally the first tests I do on any VW (and ESPECILLY the older ones) I work on with drivability issues.
One other thing to look at, see if your injector duty cycle is maxing out. You even have a MegaTune gauge for that one!
2) Check the voltage at the main pump. I FREQUENTLY see bad fuseboxes and grounds causing the pumps to get lower voltages. If it looks good at idle, its also easy to hook this up so you can watch it while moving. I do this test with test number 4. If you see the pump voltage drop as you load the car up, rerun your power and grounds.
3) I will repeat what was said above in another responese, DO A VOLUME TEST. You might even find that the billet filter is your issue...
4) FInally, do a fuel pressure test under LOAD. Not reving it in the driveway cause thats crap and not going to load the engine. Get it out on the road. You can usally duct-tape the tester gauge to the windsheild so you can see it while driving. Somebody else driving is smarter though.
If you do these four things, you WILL determine if the problem is fuel flow related or not. These are usally the first tests I do on any VW (and ESPECILLY the older ones) I work on with drivability issues.
One other thing to look at, see if your injector duty cycle is maxing out. You even have a MegaTune gauge for that one!