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I have finally come to fire my fd after i have done an engine rebuild my self. I have practically left the engine in standard form. Before attempgting to fire up the engine i have tried to pull up fault codes from the ecu by grounding ten and gnd socket in the diagnosis plug (my fd is a jdm version so i'm not sure if this still works) however i didnt get any flashing lights in the instrument cluster. So i thought it was all fine.
Then i cranked the engine with the egi relay out so as to prime up the lubrication system. Oil pressure seems to be fine according to the oil pressure gauge .
I also cranked the engine with the leading spark plugs out to confirm that compression is ok and all seemed fine.
Finally i installed the egi relay and tried to fire up the engine. After a couple of attempts the engine fired for a few seconds even though it didn't seem to fire properly and then died down . After that i have made several attempts but always in vain.
Now when i try to fire the engine , cranking starts normally and then it accelerates as if the engine is trying to go on its own but it won't. If i press the throttle during cranking , the revs start slowing down. During cranking the instrument cluster initially works normally but after some time the mileage reading disappears whilst the tacho and speedometer needles start hopping . At the same time gas fumes start coming out from the exhaust ,
I have checked if the plugs have been fouled or flooded , that the crank angle sensors are correctly connected , that spark is coming from the plugs and even tried out a different ecu but still in vain.
Any body can give hints or procedures on how to start a rebuilt engine . ?
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If you see fuel coming out the tail pipe, it's definitely flooded. Remove one of the plugs from each rotor and crank with the fuel pump relay removed. Another way would be to disconnect the fuel pump. The idea is to try to fire it up with what's already in there by maintaining spark while cutting fuel supply momentarily. Make sure your starter and battery are in good shape and don't overheat the starter. If your car is manual and you're certain you're getting fuel and spark and things are connected properly, you'll definitely get it started by bump starting it. An assistant with a tow rope will get you going in a hurry....as embarassing as that is sometimes.
I have removed the plugs and cranked the engine with the fuel pump relay times so as to clear the fuel insideabout 4 times . However the last time i removed the plugs , they were not wet. so i doubt it was flooded. I also recharged the battery fully twice and always helped it with a set of jumping leads from another running car . Had been trying to pull the codes but didn't know that japanese models didn't have the cel. Will try to pull them with a meter or an led as suggested. There might be something wrong somewhere ; even though i doubt that cause i have been checking things over and over just to make sure that its all fine.
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Always make sure there's enough gas in the tank. My brother and I tried to get a rebuilt engine going after 5 hours of no gas in the tank. A stupid mistake, but an easy one to overlook.
Had been trying to pull the codes but didn't know that japanese models didn't have the cel. Will try to pull them with a meter or an led as suggested. There might be something wrong somewhere ; even though i doubt that cause i have been checking things over and over just to make sure that its all fine.
Don't waste your time with pulling codes. Even if you had all emissions components disconnected, it would still start. It will spit out a ton of codes, but it will still start on a stock ECU nevertheless. Start from the basics: compression, fuel and spark. Confirm all three. I'm not sure if you're running a 100% stock setup or if you've removed or upgraded anything. If you've modified your wiring harness in any way, make sure you didn't cut anything that shouldn't have been cut. It sounds really silly, but it does happen.
Always make sure there's enough gas in the tank. My brother and I tried to get a rebuilt engine going after 5 hours of no gas in the tank. A stupid mistake, but an easy one to overlook.
That's like the first thing I would check...the easy fix and pray that it works.
tank had fuel in it and i put another 25 liter which should be enough. guage marks 3/4 full. I have checked the plugs and wires and they work cause i got a shock myself and i have seen spark. I have checked the wires a number of times and they should be fine too. Just to make sure : ign coil next to firewall goes to rear trailing plug , top centre coil goes to front leading , bottom centre goes to rear leading and front coil goes to front trailing. Engine is totally in standard form . I have only changed exhaust , intake box , intercooler and piping and turbo compresser wheels ; But all of these shouldn't effect anything during engine start up . i'm just not sure about the boost sensor but how does that effect the engine on start up ? How do i check the tps ?
Checked the crank angle sensors too. Correct me if i'm wrong . The white plug is on top and the grey one at the bottom right ?
Yep, that is correct.
See if you can find some Marvel Mystery Oil or some ATF (Automatic Transmission Fluid). Insert some into the spark plug holes and then manually crank the motor around a little. Then try to start it again. Make sure your plugs didn't get fouled.
When you did the rebuild, did you have your fuel injectors cleaned or anything while they were out?
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didn't clean the injectors . i had even bought the seal kit to rebuild them but never had them done. However i doubt that the problem is coming from there as fuel fumes are coming out of the exhaust just like smoke . So i guess they are working fine and so are the fuel lines right ? Have also tried to take the plugs out but the last time i did they were not fouled. I am getting desperate here as all the things seem to be in there place. There must be something stupid i have missed out . Its strange though cause the engine started twice for a few seconds but then died down.
The fuel injector comment is legitimate, you should have them cleaned. Trash can get stuck in an injector and cause it to stay open, believe it or not. Also, how long did your build take and where did you keep your injectors? Fuel turns to a solid over time and even if it's still liquid, deposits deposit and trash gets in there.
Having said that, I believe revhard, finnicky and others are right. Check vacuum lines and your tps or map sensors. Those are the next things to check after air, fuel and ignition are confirmed, which it sounds like you've done.
You have just scared the SH### out of me. Seems i will have to take the injectors out again and that's a pain in the arse to the with the engine in place. Rebuild took me just over a year since i have upgraded all the necessary things in trying to make the engine as reliable as possible . The injectors were placed on a table top facing down as soon as i took them off the engine and sat there for all that time. I doubt that the problem is coming from the vacuum lines as i have replaced every single one of them with silicone hoses and i have double checked every one to make sure that they are all going into the correct position. Boost sensor is connected too . TPS is connected but how can i tell if the last two are working properly.
An injector that is stuck open will dump so much fuel in there if you keep trying to start the engine that you would literally see fuel dripping from less than perfect exhaust joints here and there. Keep in mind that if you had some old fuel in the tank and added some fresh fuel, you would have only mixed what was in the tank. The lines could have still had some old fuel, which could quite easily flood a freshly built engine. It's always best to purge what's in the lines first. I hear no mention of a compression test. Fresh rebuilds don't always generate full compression at first, as compression quickly builds up as the engine starts running and components start to seat and break in. Cut the fuel and do a compression test...it'd be best to rule that out too if you can. Also, are your feed & return fuel lines connected correctly?
Change spark plugs new plugs will foul and look perfect, put about 4 oz trannie fluid in each leading plug hole, and have someone pull you to start it in secound gear. If it starts keep it running checking it does not over heat. Injectors will go bad just setting, low milage j spec engines ive seen were so stopped up they wouldn't run! Bye the way just change the leading plugs. Good luck!
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so now i replaced the fuel , put the throttle cable on the inner sprocket ;closest to the throttle body (not quite sure if this is correct ) , put oil in the spark plug holes and then tried my luck again . To my amazement the engine fired up straight away with the turn of the key . However there are still some problems . The engine didn't seem to work properly judging by the tune it made. It also idled slightly faster than normal and at certain intervals seemed like it tries to speed furhter up up a fraction of a second but then keep on working regularlly. I also noticed that when the engine was working the instrument cluster gave no reading except for the oil pressure. That is i had no fuel , water temperature , tacho , or mileage readings at all . I then left the engine running for a couple of minutes and put it off to check whether the oil and coolant levels were ok . These were fine but when i tried to start the engine again i got the symptoms i had before. Had to put oil again in the plug holes to fire the engine a second time.
You need to get the gauges fixed so you know what the temps and pressures are. But the motor starts and runs , until its tunned and has some run time it may be hard to start.
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The srange thing is that before i started the engine , the fuel gauge and mileage reading functioned properly and the tacho used to hop when i cranked the engine . However after starting the engine none of them did.
As For tuning . I am still running on the standard factory ecu at the moment. Does the ecu need to go through the learning procedure . If so how does this work and how long will it take to functioin normally ?
Linear Mode
