Here?s the problem I am having with 1990 300ZX & what has been done so far. Removed old engine due to internal faults ( valve & piston ring problems ) buy secondhand engine (out of 1995 model) & found cylinder number 1 exhaust valves leaking during cylinder leakage test, remove cylinder head & have valve replaced. Reassemble motor with new timing belt & fit to vehicle, motor would not start. Recheck valve timing & found all OK, decode computer & found fuel temp & knock sensor fault codes (neither will stop engine from starting). Check with Nissan & found computer to fit 1995 model has different part number. Get correct ECM for engine & found still will not start, check all engine & ECM earths, check crank angle sensor & found OK. Check fuel pressure & flow all OK, found fuel rail contaminated, cleaned out rail. Check spark & found all OK, check all engine & engine bay wiring connectors found all OK. Recheck ecm codes & found no faults present (code 55) redo compression test and found all OK. Any thoughts?
If there was some contamination in the fuel line that could lead to contamination in injectors as well.
I know its obvious and all the rest but you would not be the first to have done so (if you even have) but - check the fuel lines are on the correct way around.
Check your cas is about center on the bolts. Take it out inspect the pin that drives it and be sure it is not snapped. Turn cas by hand and confirm you can hear injectors firing.
http://www.aus300zx.com/forum/showthread.php?t=335755&highlight=test+mode The link was posted by one of the Mikes. How confident are you of your wiring? I am surprised you don't have any error codes. PS, what about that test mode on ECU?
Disconnect the rubber hose at the air flow meter. Have someone crank the engine & you spray Aerostart or something similar into the airflow meter. If it starts, it's a fuel problem. If it doesn't start, it's an ignition or lack of compression problem.
Thanks for your replies, As mentioned spark & fuel pressure & compression all good, injectors are all firing (plugs are wet). CAS is working.
How's the key in the CAS? 100% sure it's in the right spot? Does it cough or show any signs of life when you go to start?
sounds like you fouling plugs change them and try again , but this time after 5 or 6 turns of the engine pull a plug out and have a look at it and see if its still wet if its wet then your overfuelling have you got an adjustable fuel regulator , turn it down
Sorry for the hijack, was told I had a spark issue with the new tt, would hesitate and not hold idle, tried start ya bastard and it kicks over and runs fine for the few seconds the additive lasts. Guessing my issue is fuel? running rb25 injectors as per my other post, he said he double stacked the o-rings into an s1 rail
Thanks everyone for your input. Fault has been located, we just didn't look far enough when checking fuel presence. The 95 NA motor came out of an imported half-cut. Fuel line was contaminated. Cleaner put thru but we only checked the first plug for fuel presence. The other 5 were still contaminated. Even though they were clicking the fuel wasn't dripping! Cleaner put thru injectors and engine starts, however missing on at least one cylinder. Will try more cleaner under pressure & run motor. If it clears good. If not ,will replace injectors.
Double stacking O-rings is not a good idea under any circumstances, as it is actually a weaker seal. You would do much better to use backup rings as used in hydraulic systems. If you are going to fix the O-rings, you might as well have the injectors serviced while they're out.
Yeah it feels like it isnt holding fuel pressure unless you have your foot on the gas a touch and then it kind of levels out. Sourced a set of stock tt injectors from Madcow, will swap them over when they arrive. Which also means I might as well bypass crap under the plenum too.
Would advise you have the injectors serviced & flow tested prior to installation. Hopefully they will turn out to be a matched set. A fuel pressure test prior to removing the injectors & one after the installation of the serviced set may provide evidence supporting your suspicions.
