WOT Tuning Questions..

T3Bunny · Post by **T3Bunny** » 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!

captain16vgti · Post by **captain16vgti** » Sat May 27, 2006 5:37 pm

Thanks for the replies guys. I will definitely run a flow test on the pump and see what happens. At the moment all the fuel line is new including the fuel tank its self.

I will run multiple tests tomorrow and keep you guys updated on the findings. Also, Here in the link to the fuel filter I purchased. Check it out and let me know if this could be it. Thanks again guys.

-Chris

http://store.summitracing.com/partdetai ... toview=sku

djandruczyk · Post by **djandruczyk** » Sun May 28, 2006 11:01 am

captain16vgti wrote:Thanks for the replies guys. I will definitely run a flow test on the pump and see what happens. At the moment all the fuel line is new including the fuel tank its self.

I will run multiple tests tomorrow and keep you guys updated on the findings. Also, Here in the link to the fuel filter I purchased. Check it out and let me know if this could be it. Thanks again guys.

-Chris

http://store.summitracing.com/partdetai ... toview=sku

Get rid of that filter and use a continuous flow EFI filter.. The filter you have now is for Carb setups ONLY, and not resigned to handle the flow of a constantly recycling EFI system (feed/return)

From site: "Designed for carbureted systems..."

A proper EFI filter is at least 2-3" in diameter and 4-6" long or larger . Those tiny inline buggers you got are for carb systems and are NOT for return style constantly circulating EFI setups.

T3Bunny · Post by **T3Bunny** » Sun May 28, 2006 11:41 am

A good filter to use is the VW one. Ask for one for an A3 Golf. It has ends you can push/clamp hoses onto.

keithmac · Post by **keithmac** » Sun May 28, 2006 1:45 pm

Yeh the stock filters are massive!

captain16vgti · Post by **captain16vgti** » Sun May 28, 2006 6:40 pm

Hey guys, Thank you all very much for the help. I pulled the filter element out of the filter and what do ya know. The car ran great. So you guys were definitely right about the filter. I went to my work today and ordered a mk3 filter and a mk1 filter.

I would rather use the mk3 filter because of the barb fittings but im afraid the barbs them self's may be to small. Im not sure if its gonna have 5/16 or 3/8 barbs on it. If they turn out to be 5/16 I will just use the mk1 filter with some adaptors. Thanks a million guys.

-Chris