mattwelcer

Regarding the cruise control, you got it from ebay.de so presumably its for a LHD car. Did the wiring loom fit 1 to 1 or did you need to do some extending and modifying? Awesome thread really enjoyed reading through it!!! :)

I recently did this on my set of Samco's that had been installed for a few years! In the old hoses from the Throttle Body (the hose from the bulkhead to cylinder head to TB) there was a one way valve in the small part that goes or comes (can't remember the flow direction) from the TB. I had to cut it out of my old hose and then just pushed it into the Samco hose.

Oh also swaped air intake temp sensor, blue temp sensor, fuel pressure regulator & fuel pump!

Ok looks like the problem is finally solved! After swapping out the ECU, spark plugs, ht leads, coil pack, MAF, original intake airfilter and cams. It turned out to be the injectors, even though they'd been refurbished a year ago...

OK a year has gone by and i haven't managed to solve this problem. I checked the Fuel Pump relay (Postion 12, No. 67) and it is receiving no switched earth from the ECU which comes from PIN 6. If i put an earth to this PIN on the ECU directly from the negative terminal of the battery then you can hear the relay click and the fuel pump primes as normal. So to me this rules out a problem with the wiring. However this has had no affect on the start issue. I checked the Crank Sensor today as per ELSA. The crank sensor has a value of 900ohms which is within the tolerance (480-1000ohms). I checked how much resistance is between the white connector and the ECU PIN1 & PIN67 ECU, PIN2 & PIN68 ECU, PIN3 & PIN56 ECU and all had very low resistance 0.3, max. tolerance is supposed to be 1.5ohms and none of the wires are shorting to each other. I have replaced the MAF with a brand new one and a 2nd hand ECU with the same BOSCH/VAG number but that too has the same problems. Therefore what should be the next step, check all the earth points? Or recheck the spark plugs? Once the car starts it runs fine, seems to have ample power and never goes out or stalls.

I know this posts a little older but in that picture the green arrow is where the oil filter housing connects to, the yellow arrow the oil cooler and the red arrow is the crank shaft sensor.

Haven't seen it before, what i have seen is just a "standard" non return valve without any tubing. This is the part no. 1H0 998 759 but as far as i know it is no longer available from VW... Have you checked the voltage at your fuel pump between PIN 1 and 4 with the ignition on and is your relay clicking to indicate it is allowing voltage to the fuel pump? I have a similar issue but mine seems to be either a wiring problem or possibly the MAF (which I have just replaced but need to see if its the cure). As when i disconnect my old MAF it starts straight away!

Thanks for the info Si but not sure how relevant it is as I forgot to mention mine is OBD2 and therefore doesn't have the ECU relay and has the 4pin MAF, coil pack and the electric TB. What i found out last night is that if i disconnect the MAF the fuel pump receives 5Vand the fuel pump relay clicks. Therefore I guess I need to see if the MAF or MAF wiring is the problem...

I have a odd start problem with my VR6 I appear to be getting no voltage at the fuel pump (roughly 0.9V) and the relay doesn't click. If I remove the relay and bridge the large pins 87 + 30 (bypassing the relay) the fuel pump has 12V and runs. So I checked the pins at the relay and the one that appears to be the problem is Position 85 which comes from the ECU and I believe it is ground (wire colour Yellow/Blue). On the ECU this is PIN 6, if I ground this pin to the battery (using a probe in the back of the pin with a cable directly to the negative terminal on the battery) then you can hear the relay click and the fuel pump runs. Also if the voltage is measured at the pump then it shows battery voltage and the car starts fine. So this to me rules out bad wiring from pin 6 of the ECU to the plug on the back of the relay panel and the relay/fuse panel itself. Today I received another ECU with the same part number, plugged it in expecting everything OK but I still have the same problem. Therefore what tells the ECU to give ground to pin 6? As once the car is started it runs fine and doesn't cut out while driving.

I have a odd start problem with my VR6 I appear to be getting no voltage at the fuel pump (roughly 0.9V) and the relay doesn't click. If I remove the relay and bridge the large pins 87 + 30 (bypassing the relay) the fuel pump has 12V and runs. So I checked the pins at the relay and the one that appears to be the problem is Position 85 which comes from the ECU and I believe it is ground (wire colour Yellow/Blue). On the ECU this is PIN 6, if I ground this pin to the battery (using a probe in the back of the pin with a cable directly to the negative terminal on the battery) then you can hear the relay click and the fuel pump runs. Also if the voltage is measured at the pump then it shows battery voltage and the car starts fine. So this to me rules out bad wiring from pin 6 of the ECU to the plug on the back of the relay panel and the relay/fuse panel itself. Today I received another ECU with the same part number, plugged it in expecting everything OK but I still have the same problem. Therefore what tells the ECU to give ground to pin 6? As once the car is started it runs fine and doesn't cut out while driving.

Did you get any further with this issue? I managed to borrow a manometer to test my fuel pump and fuel pressure regulator, turned out all are fine. Measured the voltage at the fuel pump and its on 0,8V (hadn't heard the pump priming either lately) So gave a direct 12V feed where the Relais goes at pin 4 and suddenly the pump was working again. So my problem seems to be the relais (No. 167 at position 12) seems to be half working (fine when cold, cooler temps). Ordering a new one on Monday and hopefully that will cure my hot starting problems!!!

Nice! :)

Do you have part numbers for the "plastic ring"? I can only find part numbers for the o-ring and the sensor in ETKA but nothing for the plastic ring... ---------- Post added at 12:51 PM ---------- Previous post was at 12:46 PM ---------- OK doesn't matter now, I don't need the plastic ring as i have the later sensor 021 906 433 C which doesn't require the ring.

I am pretty sure a Lambda is necessary for the car to run "properly" as it tells the ECU if the exhaust gas is rich or lean, therefore the fuelling is adjusted by the ECU. I think at idle the Lambda is not being used. I think if the ISV was faulty your idle wouldn't be stable and the throttle cable shouldn't have any impact either.

Ok it seems it was the Fuel Pressure Regulator and that 4bar is too much, with the 3bar it starts fine every time. Guess i'll have to see if a remap can solve it as i know it runs lean and runs better with the 4bar but doesn't start as well :(