My car seems to be running on 4 cylinders....done a few tests that seems to confirm this but I can't seem to fix it....any help appreciated!!!
This is what I've tested so far. Removed the plugs from the injectors one by one, idle should drop. Idle dropped for cylinders 1-4 but removing the plugs from injectors 5 and 6 made no difference to idle.
This can indicate bad injectors so I removed the fuel rail while it was still connected and cranked over the engine. Fuel sprayed from all injectors and none of them had irregular spray patterns. So it was getting fuel ok.
Also tested the fuel pressure and it was spot on 250kpa. So the pump and reg are ok.
Next I tested for spark. Got a spark plug, opened the gap to 6mm earthed it with a jump lead and hooked it to cyl 5 and 6 spark plug lead one by one. Spark was there and was ok.
Next I started the engine and removed the no.1 spark plug lead. The idle got worse. Put it back and removed no.5 lead....no change in idle. Removed no.6 lead, also no change in idle. Seems as if no.5 and 6 cyl aren't doing anything.
Also you may or may not know that each turbo is running a separate manifold (3 cyls each). The second turbo is running off cyl 4, 5 and 6. If I remove the injector plug from no.4 cyl the engine starts backfiring and stuttering as if there is no exhaust gas to spin the second turbo and its just creating a massive restriction. Also, the front turbo gets a lot hotter than the second one....initially I thought this was a problem, but now I'm thinking that maybe thats normal the second turbo is cooler cause it only has the exhaust gas from one cylinder spinning it.
So if cylinders 5 and 6 both have spark and fuel, why then are they making no power??? They were fine before the turbos went on and the turbos haven't been plummed in yet so the engine is not under any extra pressure.
I also ran a ECU fault test and it showed up nothing. The car is running very rich though...I got 30ks out of 15bux.
yeah i thought of the headgasket....but it was changed not too long ago and i have not been driving the car since the turbos went on so i don't see how it could blow. Also there is no coolant in the oil :)
how do you run a compression test? is there a tool you can buy?
yeah it stinks of fuel if you do drive it. the other thing it thought of was maybe there was a air leak around one or two of the injectors and it was losing power that way...but the problem still exists after I removed and replaced the fuel rail tonight and all the 'O' rings on the injectors looked ok.
One other thing I was thinking was that maybe the turbo manifolds are restricting the exhaust flow causing a drop in power......but that just doesn't seem right....and wouldn't explain the fuel consumption.
You checked that spark plug leads and the fuel, but what about the plugs. I'd take the plugs from 2 working cylinders and swap them for the non-working ones and see what happens (just to eliminate the possibility that it could be the plugs).
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