Rallye VR6 Turbo - Updated 22-08-2008 Interior update, and more blow?

Pay attention 007!

 

DVLA I LOVE YOU!

Reg number and tax disc just arrived )

 

hahaha almost ready for the road

get the golden earring cd out ready

 

Got no stereo to put it in

Car makes all the music I need anyway

 

Well, the dodgy OBD1 loom came out on Saturday and the new OBD2 loom went in on Sunday.

So:

The cam position fault is now gone!

But:

The engine won't start.

Everyone was confused. No fault codes... Everything seems ok... No spark or fuel.

 

Very little progress since the last update. A lot of time has been thrown at the car but it's continuing to be awkward on the wiring front.

Currently, the ECU registers no faults and the car runs. There's something odd going on with the fueling system at present - it's like the pump isn't consistently maintaining fuel pressure. It has been know to us for a while that the stock VW wiring to the fuel pump isn't great for the rather beefy pump we're using but it seems the main target for our suspicions at the moment - it gets very very hot even when the car is idling. So rip that out and run it straight from the battery with a relay triggered by the stock pump wiring is the next job.

They say the last 10% is 50% of the work. How true!

 

It continues...

So, we acquired a VW fuel swirl pot and stuck that back on the car rather than having the chunky inline pump drag the stock lift pump for every mil of fuel.

In other news we compared the readouts of the MAF sensor between the rallye and another working OBD2 car and the rallye is significantly underreading. Swapping MAFs yielded no conclusions - the sensor from the rallye reads fine on the other car and the other cars sensor worked badly in the rallye.

After spending hours trawling the 'net researching sensors and finding reference values it seems the lengthened wiring can't (as far as my electronics knowledge stretches) significantly affect the readout of the sensor.

So, it looks like we have some type of power problem to the MAF...

During most of yesterday we had the fuel pump relay out because we thought it wasn't in use on the car as the pump is powered seperately... WRONG. The fuel pump relay also powers the lambda sensor heater and... yep... you guessed it... the MAF.

Half of me wishes it isn't that simple and the other half just wants it to work no matter how STUPID it makes me look.

Fingers crossed... a bit.

 

sounds like fun!!! must be running out of patience now, itching to drive the thing?!?!

 

Definately.

 

I am too, and I don;t even own the damn thing

 

So, a slightly short day fiddling with the car shaped brain teaser that is the rallye today but a semi-productive one.

I believe we now officially hold the record for the long amount of time spent fixing two numberplates and a front grill to a car. I thankyou.

On the road the car is (going to be) awesome. You can hear every last sound it makes - the turbo whistle, the dump valve, the wastegate... the pinking...

We wired up the fuel pump direct from the battery and unfortunately it made little difference. After removing a buggered fuel pressure regulator fueling got a bit better so we began to push the car a bit more. At present as soon as it hits about 3500rpm (by which time it's made 0.5bar boost (oh goodie) it starts to knock like a bar steward. The cheaky VR6 rascal made a map that relaxed all the ignition timing and we tried again... same result. ****.

At the end of the day we've ended back at the mysterious under reading of the maf. Something that we can account for in the map but something that I/we would much rather just fix properly.

So, hopefully next time we'll crack it. So far for the last few months its been a continuous string of little issues that cause big problems.

 

have you had 800 gallons of help?

 

More than that

Delayed update:

I took a day off work last week to have a play with the car.

After a few hours of prodding everything in sight with a multimeter we have confirmed that the voltages to the maf sensor are all correct and the voltages to the ecu confirm what the maf is supposedly reading on the ecu.

We started comparing every inch of pipe to that of the working car a few yards away. Both cars have custom fabricated maf housings but there are some critical differences.

The tower that the maf sensor sits in on the rallye was taller than that on the working car and the rallye also has a 3 > 4" join and corner right next to the maf element.

So, we chopped 15mm off the top of the tower the element sits in and the car instantly ran better - confirming suspicions. The car is now 10% out fueling wise rather than 30-40% so a vast improvement. I have on order a genuine 4" housing so hopefully it'll arrive this week and the car will run correctly.

Just need to locate some front bumper indicator wiring now after some light fingered chap half-inched mine!

 

After a few weeks worth of wait all the bits arrived from various corners of the world and were put on the car.

Result: It's alive and runs SPOT ON.


GET IN!

 

sweet

 

nice look forward to seeing it some where

 

Good work. When's it going to make it's public debut then?

 

Dunno really. Gonna get the tracking and suspension set up this Saturday and bring it home. Loads of cosmetic stuff left to do but it'd be rude not to pop in to a few meets now it's on the road I don't really know when stuff is happening as regards the VW show/meet calendar but I'll definately try and make an appearance sometime soon.

Main thing wrong with the exterior at the moment is the boot lid being a completely different colour. The interior has had no attempt made to make it look good as yet. Under the bonnet she's mint though and that's where the fun is

 

Nice one!