I've had a bit of a headache since getting my Nissan sr20 det rebuilt! It's got new low comp je pistons. Since I've tried to get the engine started it's only fired on two cylinders. After a lot of checking, one of the issues was; I had some fuel left in the tank, which had been there for two years and this had gone off, it looked like lime scale at the bottom of tank. As its only ever gone on the back and front cylinders, fuel was getting into the cylinders and the oil has got fuel in. I changed the oil and filters, the fuel tank and pump is changed, I sent the omex 500 ecu and loom to omex and they checked the ecu, this was okay, there was a diode for the rev counter that was suspect, its been tested and omex said this is okay on all four cylinders. Before I try to run the engine back up there's some black stuff on top of the pistons which looks a bit gummy, I think its some of the old fuel! How can I clean this best without removing the head? Any ideas would be appreciated, I'm stumped!!

Jim

 

It will probably burn off when the engine is running properly. You could try a squirt of redex or something down the spark plug holes, leave it for a day or so to soften it up.

 

Thanks I was thinking of something similar to this , would it do any good to squirt redex or similar leave a couple of days then turn over with the plugs out ?

 

Pour some of this down the plug hole, it'll clean and condition them....and make the exhaust smell nice.




And if it's only starting on 2 cylinders, either the wiring is not right, ecu setup not right, or you have some faulty coils or injectors.

2 year old fuel isnt so old it should present any problems to starting a car.

 

Thanks Steve, I had tried changing the coil pack first, then got another set of injectors. I sent the loom to omex and they thought there was a couple of issues with that , my mate thinks that type of engine management initially is 2 cylinders then doubles up for 4 6 8 etc this is why I thought it was down to this end of things .

 

There are many reasons why it could fire on only 2 cylinders as mentioned.

No sense changing the coil pack, until you have tested if both sides of that coilpack are actually receiving a signal from the ecu.

Likewise changing injectors.

 

Ill let you know how it goes when I get the bits back together .