I REALLY REALLY NEED HELP!!! CAR WONT RUN!!!

[hoosier240sx]

Alright so I have a freshly rebuilt motor with all emissions removed. when the motor was pulled out of the car it ran flawlessly and now since i have put the motor back in the car it runs like total a**. I would have to type out a million things to explain so I made a video for you guys. This car also went through a SOHC Ka to DOHC swap and I did the wiring myself, I havent check the connection where i soldered and I'm now not too confident that I did a good job. This was my first time building a car/motor and all my workmanship was done according to guides off of here.

http://www.youtube.com/watch?v=axRrjosIUQw

Sorry for the link I really dont know how to post vids from youtube, only pics :/ what can you expect though I cant even get my car to run again.....but please if anyone can tell me what is wrong with the car I would greatly appreciate it!!

[AZhitman]

Whoooo. This could be a big job.

When you removed all the emissions controls, did you do away with the IACV? That's gonna be mandatory to replace. Let's start there and work our way through.

[biggie]

Looks like IACV is there, at least hose is going to it.

Something to do with TPS or something? I couldn't tell what the loose connector was around the TB.

[Hoffman5982]

so...you aren't confident in your quality of work on something, but instead of checking it you go through the trouble of uploading a video and starting a thread on here?

[hoosier240sx]

so...you aren't confident in your quality of work on something, but instead of checking it you go through the trouble of uploading a video and starting a thread on here?

I checked the wiring right after and it checked out, i was confident in it but everyone told me to start there. and yes the iacv is still there, the motor ran perfectly when it was pulled out of the other car so idk whats wrong now. i think its the MAF, but no one by me as a 240 so i cannot swap them. when i start the car it runs rough and smokes really badly, but its grey/white and not blow or anything like that. and Hoffman if you dont have anything substantial or helpful to say id rather not read it, i posted in here first because i figured someone may have had this problem before and could tell me what it is before i go off and check through eerything when it could be something basic.

[allenms240]

Is that about all? It just dies right off the bat? If that's the case, it sounds like it is a vacuum leak or the IACV, I'd clean that and made sure all connections are good. Check all hoses for rips or tears.

Does it run okay with the throttle kept constant? Or is it rough, choppy, misfires, etc?

all ka24DE parts used I'm assuming, the maf and ecu.
Could be the maf because when it is unplugged, it runs like crap but dies what it's plugged in. I'd start with the IACV and then the maf.

[moso]

i would start by checking the ecu for trouble codes. check the TPS adjustment. check the reference voltage coming out of the ecu to your tps and maf and make sure your getting proper voltage. check out your grounds. check for vacuum leaks. check the injectors and make sure they are seated properly and not leaking. check the ignition timing......do that in order and post back the results.

[krash]

so...you aren't confident in your quality of work on something, but instead of checking it you go through the trouble of uploading a video and starting a thread on here?

Stop being a d!ck.

I've never really seen a car shut off that quickly because of a vacuum leak. You might have some luck replacing the MAF. Do you know if the engine is flooding out when it cuts off?

[Hoffman5982]

Stop being a d***.

I'm sorry, but how was I being a d***? I was simply pointing out that even he questions himself on something yet hadn't checked it

[Hoffman5982]

Also, timing sounds fine, although that doesn't mean it is. You say it runs rough but the few seconds that it is kept running it seems to run ok. It's not shaking like crazy or anything. As everyone in the youtube comments, check the nipple on the left side of the intake with the red cap. Most aftermarket intakes that I have seen don't usually have a random unimportant nipple on it

[allenms240]

No the nipple is perfectly fine like that, I have that on my intake. Yeah I don't think I've seen a car shut off that fast either due to a vacuum leak. Normally it will run horrible and choke off, just just die. Same with lack of fuel, it will choke itself off, not just cut out.
So that makes me think maybe ignition timing? But it sounds pretty solid and I'm sure you've already made sure the timing was correct.
Krash, if the engine was flooding out, wouldn't it not start up again as soon as it does in the video? Wouldn't it just crank away, trying to ignite all the fuel but failing.
So far, my monies on the MAF, it's the only thing I can come up with. But give Moso idea a shot as well.

Good luck.

[krash]

Krash, if the engine was flooding out, wouldn't it not start up again as soon as it does in the video? Wouldn't it just crank away, trying to ignite all the fuel but failing.

Yea thats true. Its got to be something wrong on the chassis if you said the motor ran perfectly fine when you pulled it. Did you remove the emissions stuff after you pulled the motor? Double and triple check everything if you did.

[moso]

well you can guess the injector o rings are fine, guess you dont have a vaccuum leak, guess you have good timing, guess that the maf may be bad. or, you can check things and be sure.

[hoosier240sx]

Ok I have been thinking all along it is either my MAF or my ECU like all of you have said and I know for a fact that all of the emissions was properly sealed and I know 100% that this motor ran absolutely perfect when it was pulled out of the other car. i can't really check the ECU for codes because when you swap a DOHC over to a SOHC chassis you have to cut the diagnostics plugs from the dash harness. But like everyone else has said I havent seen a vac leak cut the car out right a way, the car runs rough and shakes the chassis a little(yes i have solid mounts, but more than normal) and then as it warms up it slowly starts to bog out and dies. And Hoffman no worries man I understand I jumped the gun and probably posted too early but I tried to figure it out all night and all that day before I posted it so I was mentally exhausted, I'd probably have the same response as you.

But here is what I am deciding to do, I'm going to drive 2 hours to my buddies house and snag his MAF and ECU off his car and plug them both into mine and see if either or is the problem. I know the dude who sold me both of mine was a shady f***, but needless to say I took care of him, so these could be the problem. So if anyone has either of these parts up for sale that work PERFECTLY I would love to snag them off of your hands. Also does anyone know where that connector goes that i grabbed from my trans? Is that the speed sensor or what? cause I cant figure out where the hell that is supposed to go...

[breadbox]

sounds like my project hatch.

Grab a can of carb cleaner and keep it gassed and check for major vacuum leaks.

I am almost positive you have a leak.

I swapped ecus and harnesses and tps and all that, then I found a vacuum leak between upper and lower intake.

[moso]

i can't really check the ECU for codes because when you swap a DOHC over to a SOHC chassis you have to cut the diagnostics plugs from the dash harness.

you can wire up the diagnostic plug where the harness goes into the dash harness, just snag a plug off any like year nissan the TX and TX wires are the same color in the plug as in the ecu harness, then you just need ground and power and your set. I made a walkthrough a long time ago and got flamed all to hell for it because "thats old news", guess its not old to some aye. anyways you can just set the ecu into code mode from the dial on the side of it and watch the light. if you need the walkthrough for the diagnostic plug i can send it to you as i have done it to my car and i have a dohc swap....with consult!!

[compactfean]

^did this with my sr.....best thing I ever did. You can see the while picture then, love it

[hoosier240sx]

i can't really check the ECU for codes because when you swap a DOHC over to a SOHC chassis you have to cut the diagnostics plugs from the dash harness.

you can wire up the diagnostic plug where the harness goes into the dash harness, just snag a plug off any like year nissan the TX and TX wires are the same color in the plug as in the ecu harness, then you just need ground and power and your set. I made a walkthrough a long time ago and got flamed all to hell for it because "thats old news", guess its not old to some aye. anyways you can just set the ecu into code mode from the dial on the side of it and watch the light. if you need the walkthrough for the diagnostic plug i can send it to you as i have done it to my car and i have a dohc swap....with consult!!

Yeah dude definitely send me that cause I'd really love it have it. And I am almost 100% positive it is not a vac leak there is no reason why it would run until it warms up and then bog out and not start again. It just doesn't make sense.... But anything is worth a shot so i will try. To use the carb cleaner just take the whole intake off and spray it in the throttle body correct? Just triple checking cause I don't want to make any more problems for myself..... but with my little expirience and knowledge on cars im dead set that its either my ECU or my MAF. I called the dude before me and he said that the ECU "was running a chip at one point" but I have no idea if that would affect the unit after the chip is removed? I am borrowing a friends ECU and MAF tomorrow or saturday so I will know for sure then. Let's hope its that simple....

[AZhitman]

No, don't take the intake off. To check for a vac leak, have someone maintain throttle so the car runs. Spray starting fluid (not carb cleaner) around the plenum and intake connections (wherever a leak is likely). If idle speed fluctuates when you hit that spot, there's your leak.

[hoosier240sx]

So my friend brought to my attention that my MAF doesn't have the screen that is supposed to be inside it. I'm pretty sure that this is the problem, I would say that I am a dumbass but this is the first car I have ever built/worked on so I don't feel too bad. Let's hope that getting a new one works

[compactfean]

Yes those screens are very important to prevent turbulence. I know from a6 month diagnosis I did.

[Armstec_S13]

i noticed in the vid, your intake doesnt have the big hose at the bottom of the intake put in, i paused the video on 0:43 seconds, there should be a big hose the connects in there, i have a single cam with that same injen intake that is for a DOHC motor, my hose was too small for that hole and it came out one time, car did the same as yours, find out where that hose/tube goes and you should be fine


just ran out and made a video, hope this helps

http://youtu.be/-YowQqwi9ME

sorry, dont know how to imbed the video

[hoosier240sx]

The big hose at the very bottom of the intake goes to the fan shroud for the radiator and is irrelevant on the DOHC motors. Thanks for the time and effort you put into the video though I really appreciate it.

[Armstec_S13]

The big hose at the very bottom of the intake goes to the fan shroud for the radiator and is irrelevant on the DOHC motors. Thanks for the time and effort you put into the video though I really appreciate it.

no problem, tried to help with what i could, good luck to ya bro

[allenms240]

That hose (mines is just plugged off) goes to a box in the fan shroud correct. It is used so that if water gets in the intake, it can drop down into the fan shroud, where if won't do any harm, as opposed to getting into the motor.

Good luck with the MAF, report back.

[hoosier240sx]

I changed the MAF out with my buddies and it wasnt the problem, the car still runs like complete a**. I'm legitimately stumped dudes, the last thing I can think of changing before i go and tear my wiring harness apart would be the ECU. I really want to know how to wire up the Diagnostics, I wish Moso would get back to me on how to set all that ish up...

[krash]

That hose (mines is just plugged off) goes to a box in the fan shroud correct. It is used so that if water gets in the intake, it can drop down into the fan shroud, where if won't do any harm, as opposed to getting into the motor.

Thats actually a resonator to quiet things up IIRC

Yes those screens are very important to prevent turbulence. I know from a6 month diagnosis I did.

I'm not sure chief. Both 240s (factory specs) I've had haven't had them. I've only seen that screen in one 240 MAF and an altima MAFs, so I don't think its really integral to the function. I figured it was just for catching extra crap.

I changed the MAF out with my buddies and it wasnt the problem, the car still runs like complete a**. I'm legitimately stumped dudes, the last thing I can think of changing before i go and tear my wiring harness apart would be the ECU. I really want to know how to wire up the Diagnostics, I wish Moso would get back to me on how to set all that ish up...

That sucks. Lets hope the ECU works? I'm stumped man.

[allenms240]

Well, I'd check the nifty, handy, dandy, startup triangle. You need fuel, spark, and air. You've got air (it seems), it doesn't appear to be fuel (it's cutting right off, no stutter whatsoever), my guess is something spark or electrical :/. That's the hardest of em all of course.
You say it runs good for a while till it warms then cuts off, then starts up and dies as in the video? Hmmm. A lot of diagnostics ahead of you my friend. Next, I'd check ECU (although I doubt that's the problem, it's the easier of the diagnostics.) After that fails, wiring. If the motor ran flawless before, I'm guessing you might have messed up somewhere along the lines on the wiring (no offense, just a thought).

Krash,
Meh gave it a shot, didn't make THAT much sense to me, your reason sounds much more acceptable . Learn something new every day.

[compactfean]

Long story short, I've got a z32 maf and couldnt take my motor over 6500 rpm without a huge hickup or misfire. After months of reading and diag and research I came to find out that my z32 maf was missing a screen. I used a screen from a junk maf and put it on and bam .. All the way to red line. Then just to see if it was a fluke I took the screen back off and problem came right back...lesson to be learned, screens are there for a reason other than debre.... To stop the turbulance from affecting maf voltage signals.

[moso]

heres that link, thought i posted it earlier but i put it in the wrong thread!!

post5015248.html#p5015248