Hi all. I have been reading the posts titled 'Rough Running'. My G developed this fault about 5 years ago, where I would start it up from cold and the car would be hunting, and over fuelling. After a minute it would start running perfectly.
After one year of trying to solve the issue, the car suddenly would not idle without staling, I had to use the throttle to keep it running, and had a massive flat spot. During that year I took it off the road and replaced everything ie - both fuel pumps, ignition barrel switch, 3 ECU's tested, distributer, knock sensor, injectors, engine etc....
The only exception being the engine loom (due to high cost), and Clifford alarm system which I bypassed. I did lay two 2nd hand looms to try and rule out the engine loom, unfortunatly this did not resolve the issue.
I managed to get the car running with the lamda probe disconnected and the CO/air temperature sensor set at 5.50 ohms - rich running. The car still started as badly, but it meant that I could use it. I noticed when i intinally footed it that the exhaust smoke from over fuelling (noticed when being followed by a car that had xenon's) was not consistent, but the car did not feel like it was surging. When I checked the ignition timing it was not steady it was advancing and retarding by 6 to 28 degrees.
After replacing the blue water sensor, lamda probe, ignition leads, distributor cap, rotor arm, spark plugs, and coil. Some of which for the fourth time. The car ran fine for approx 2 months other than the continuing flat spot. Then without any reason I was back to square one.
I am really getting pissed off and was offered an Emerald K3 ECU for a very good price. I am currently in the process of building a new stock engine loom, as I suspect that the shielded cable has broken down due to age and the HT wires are scrambling the information being carried to the ECU. If I still do not get any joy I will have to try the emerald. I am also having a new Clifford fitted soon.
During the last five years, I have consulted two G40 specalists neither of which could help. I have bought Snap On diagnostics machine, fuel pressure testing equipment, and VAG's engine workshop manual and pin data from Autodata specifically to try and find out what is wrong.
In June 2008 one of the charger belts snapped, wrapped itself around the crank pully, and cam belt cover. After working it's way down, got pulled into the cam belt, resulting in the cam belt snapping : ( The head was replaced with a BVH, port matched GT inlet manifold, port matched exhaust manifold, de-wedged throttle body, refurbished injectors, and an R1 charger rebuild with 65mm tooth belt conversion from Austria. The car was then live mapped at Jabba sport, and made 147 BHP on 95 ron fuel. At the G40 rolling road day later on in 08 the car made 137 BHP!?
After engine loom has been tested I will report back, unless someone else has a breakthrough.
PS - I thought I was the only one experiencing this problem.
