Hard starting and rough idle.

[Deviousjet]

Hey guys finally got my 240 running from rebuilding it but found a couple problems. I did the egr removal, Took of the pipes off of the back of the header and also took of the actual egr on the intake manifold and put a block off plate on the sucker and now the car starts fine when it's cool, but you have to hold the gas to keep the car alive. Checked the maf it's fine, and there is a weird suction noise coming from somewhere on the intake mani, but the weird thing is the car drives like it has power. It runs and I drive it but when i come to a stop the motor just dies on me. Any ideas? this shit is getting expensive as hell and I'm running out of ideas. i'm changing out the spark plug wires because those were shit, and Am contemplating reinstalling the EGR. Please help!!

[slothonaleash]

vacuum leak

bam done

done again

[Deviousjet]

But if it were a vaccum leak wouldn't it have a problem even running? this car drives like it's fine. But once you stop dead. Why would it have power and still run? Sorry not trying to argue i'm just trying understand the situation.

[slothonaleash]

Vacuum leaks only noticeably affect idle.

Quitchya arguin :)

[Deviousjet]

Ok. that helps. Thank you. Now there's one more problem. I go to turn it on the first time it cranks, starts up fine. Then once the car warms up the car cranks cranks and ccranks for about 15 seconds then a little puff of smoke comes out of the end of the exhaust and the car lazily comes to life. What could that be?

[jspeedm]

Vacuum leaks only noticeably affect idle.

Quitchya arguin :)

can i argue?

it could also be idle air valve or throttle body.
best way to check is to hook up a scanner and look at long term fuel trim. if it's high= vacum leak. if its close to 0 = tb or iacv

more than likely ^^^^he's right.

[DC29]

Ok. that helps. Thank you. Now there's one more problem. I go to turn it on the first time it cranks, starts up fine. Then once the car warms up the car cranks cranks and ccranks for about 15 seconds then a little puff of smoke comes out of the end of the exhaust and the car lazily comes to life. What could that be?

im thinking toasted piston rings. heres why. heat makes metal expand, so when its cold it has enough compression to fire up and start good the first time but once its warm its a bitch to start because theres too much clearance between your piston rings and the cylinder wall, thw cloud coming out the back would be the oil getting passed your rings and burned with the rest of your fuel and what not.

as far as this hissing noise, my opinion is vacuum leak

[Deviousjet]

Damn but what sucks about that is I just ordered brand new nissan oem piston rings from frsport. But I'm not going to even pretend like that idea doesn't sound logical.

[dftsilvia]

coolant temp sensor might be bad if your having problems starting it hot.

[WangonwWarrior]

Vaccum leak for sure, that what the hissing noise is. Spray brake clean to locatie it and have fun with the search. It usually the 3 lines right behind the thermostat

[Deviousjet]

Brake cleaner or wd40 works right? What about the piston ring thing? anyone have any more insight on that?

[DC29]

what more do you want to know about it?

use soapy water in a squirt bottle. you can potentially light your car on fire spraying WD all over it and brake cleaner isnt good on alot of parts, like rubber for example, it dries it out, then it cracks, then it breaks, then your crying about having to go buy a new radiator hose or whatever it may be

[Deviousjet]

soapy water it is then .