What do you get on no 4 if you squirt a bit of oil into it and test again. Same - head (valves) Better - rings It should still fire on 90 though
I know what you mean, I thought it would still run on 90. Is there any other things that would stop the cylinder firing? VTC? Beavis
OK so I think its confirmed that there is an issue with cylinder 4. Now I need to work out what might have happened. What has recently changed.. Plenum Pull with new injectors (Flow tested and within OHM range) Water Bypass Delete AIV Disconnected EGR vacuum and solenoid but pipes still in place. New fuel lines Checked oil level and coolant levels Drove like a dream for 24 hours then it broke. I am happy to take the heads off, asses damage and fix. I would just like to get an idea of what might have caused the issues. One thought a mate and I had was that the EGR sent exhaust gases into the chamber and caused cylinder 4 to become rich with fuel (Spark plug smells of fuel and due to less oxygen in the combustion chamber thus richer mixture) and then the O2 sensor tried to lean off the mixture and this led to detonation and thus broke something in the cylinder. Does this sound plausible? Car also had DET sensor bypassed....could this contribute to the failure. Other than that I have no idea why the cylinder would fail. Cheers for all the input so far. Chris
just a thought pull the cam covers off and see if the timing marks have moved it happened to me than ran in limp mode jumped 5 teeth racing,
I will perform a leak down test. Its popping out of the exhaust and not the intake. When you drive you can hear it popping and banging through the exhaust and a strong smell of petrol through the exhaust. Chris
I'm far from saying that this is the cause but its work having a look if something fell in the bottom plenum and has jammed open the valve for that cylinder... Yeah I know the symptoms might be different to as described.... but just a thought. kind of like this..
See if you can get one of those inspection camera things. Might give you an idea if you want to replace insted if rebuild.
Haha, I thought about one of those, I think they are about $180 bit much to spend for one use. Anyone have an inspection camera I could borrow? I think I am going to take the plenum off and cam cover and see if there is any issues with the valve spring. If not I will pull the engine out and get it sorted properly Beavis
Right some more mystery. I drove the car about 2km to the place I am doing some work on it and it still idles on 5 cylinders but feels like it runs on 6 when the revs pick up. I decided to unplug injector 4 so I didn't get a build up of petrol while I drove now I am getting massive backfires out of the exhaust. I plugged number 4 injector in and still the back fires occur. Could my timing have shifted a tooth???? All seems very odd. Chris
Right some more mystery. I drove the car about 2km to the place I am doing some work on it and it still idles on 5 cylinders but feels like it runs on 6 when the revs pick up. I decided to unplug injector 4 so I didn't get a build up of petrol while I drove now I am getting massive backfires out of the exhaust. I plugged number 4 injector in and still the back fires occur. Could my timing have shifted a tooth???? All seems very odd. Chris
I think I have figured out what's wrong with my car. After driving it 4km I let it sit for 2 hours and when I pulled the fuel pipe off from the filter there was no pressure. I can only assume when I installed the new injectors I pinched an o ring and now cylinder 4 is putting tons of fuel into the cylinder and at idle its not exploding. But when the revs pick up it runs better. If I disconnect the coil pack for no 4 it runs like its on 5 cylinders but when I reconnect the coil pack it revs ok. But doesn't fire at idle. The over fuelling might also explains the crazy backfires I am getting when I come off the gas. Right time for another plenum pull and check the injectors. Beavis
This sounds feasible, so just pull the upper plenum and check the sealing ring, you will know by just looking at them if this is the problem. This does not explain the metalic sounds you got as this cylinder failed
FIXED IT!!! Then it broke UPDATE TIME!!! RIght just before pulling the whole motor out of the car and tear it all down I decided to connect the fuel rail up to the pump and run full pressure through it while the rail was out of the car. Well what do you know, fuel leaked everywhere from injector 4, the one that wasn't firing. So I took the injector out and look what I saw Pinched o-ring So I changed the O-ring and the car ran sweet as a nut. Perfect, sounded awesome. So I drove it 80km to a gig and when I went to start the car after the gig it struggled to start and again running on 5 cylinders at idle. Now the issue is on cylinder 3 I think I am going to have to do another plenum pull and change all the injector o-rings. 5 plenum pulls in 3 weeks, can do it in less than 40 minutes Whats another one Beavis
I think you are right, going to replace all the injector o-rings again and do another full compression test. A rebuild is on the cards, just got to decide options moving forward. Beavis
UPDATE!!!! Hi guys just giving a final update to this thread. I took the fuel rail out of the car and changed all the o-rings and used so much lubricant it was everywhere lol!! Anyways all the fuel injectors went in very well. I ran the fuel pump into the rail out of the car and it held pressure for 2 hours without any leaks. So put the car back together and it started straight away. All good. Its running a bit rough at idle at the moment and I think its a combination of 1 EGR bolt missing from each side of the plenum (have replacments to go in) and the Plenum Gasket being past its best after 6 plenum pulls in 6 weeks. So got to get another one as it was torn a littel round cylinder 6. Apart from that it drives well but I am not giving it any boost untill I know the plenum is sorted and I have no vaccum leaks. Just wanted to say a massive thank you to everyone on this forum!!! I am glad that I didn't have to pull the engine out and tear it down. (although I would still love to do a full degrease and rebuild but I need save $$$ for that) Cheers Chris
I think I do. I am going to do another compression test to see. Just need it drivable for a couple of months while I plan a rebuild. It revs very smooth and runs great at the moment. Just the idle is a bit lumpy. Still need to change oil and spark plugs. Will still rebuild it soon.
